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With more than 100 Roadsters delivered to customers so far and more on the road each week, it’s natural for some customers to run “experiments” on them. Because we have such an entrepreneurial and highly technical customer base, many of these experiments are quite detailed and attempt to answer questions that we have in some cases never discussed publicly.
One of the most common and tricky experiments is testing how far the Roadster will go on a single charge in various driving conditions. For the latest powertrain configuration (powertrain 1.5), we have demonstrated dynamometer test results of 244 miles range in a complicated combination of highway and city drive cycles defined by the EPA.
However, this is just one data point; real-world range can vary substantially depending on driving style, environmental conditions, and usage of accessories such as the electric cabin air conditioning system and the electric cabin heating system. The cycles defined by the EPA attempt to make a representative average of these different factors and combine it into one number. Many customers, potential customers and curious observers want the details behind this average and how results may change depending on conditions.
We need a designed set of experiments to understand how efficiently or how far a Roadster could drive under different conditions. This can quickly become a huge amount of testing as there are so many variables and conditions, but fortunately we have spent quite a bit of time internally building a very accurate computer model of how the Roadster will behave under different driving scenarios. We’ve validated the model by testing at a reduced number of points — enough to give us good confidence in the results. The details of this model are quite interesting and could be a whole separate blog, but for now let’s just use it as a tool to help us understand Roadster efficiency and range.
The simplest experiment to consider, and one that gives great insight into the whole vehicle performance, is how efficiency and range vary as a function of driving speed. This is assuming that speed is held constant (i.e. cruise control) at each point. For any test or model run, there are many inputs that need to be specifically stated to make the results meaningful. So here are some of the critical inputs that we have assumed:
• Single driver ~180lbs
• Soft top or Hard top on vehicle (with windows up)
• No air conditioning usage
• No heat usage
• No headlights or cabin air blower (large 12V loads)
• Tires inflated to recommended efficiency setting 30/40 front/rear psi
The outputs of this model run are in battery energy usage per mile. In the case of an EV this is typically expressed in terms of Wh/mile. A 100W light blub running for 1 hour will use 100 Wh of electricity. Since 1 Watt is also just 1 Joule/second you can easily convert Wh into Joules by multiplying by (60 [seconds])*(60 [minutes]). It is also important to note that we are discussing DC Wh/mile or energy coming OUT of the battery pack inside the vehicle. This is very relevant to range but does not consider the losses associated with the onboard battery charger or some of the slight round-trip energy losses in the battery itself.
Here is the DC Wh/mile predicted result for a Tesla Roadster with the above assumptions over the entire operating speed range.
The shape of this curve might not be immediately intuitive, but it makes sense once you consider the different types of drag and energy loss at work. (We will look at those soon.) Remember that this is not a power curve but instead a plot of energy per mile. You can directly determine power from this data by multiplying the Wh/mile by the mph at a given data point. The expected DC power required to drive the Roadster at a steady speed is shown below.
This probably looks more intuitive since it is always increasing as speed increases. The shape of this curve is obviously not linear. To cruise at 60 mph takes about 15kW. However, if you double that to 30kW you will only accelerate to about 80mph — far less than twice as fast. And if you double it again to 60kW you will accelerate to about 107 mph using 4 times as much power as you did at 60mph, yet you’d only travel about 1.8 times as fast.
Energy Loss Distribution:
To understand why these curves have the shapes that they do it is helpful to examine where the energy actually goes. For simplicity we will group the energy usage into four “buckets”:
1. Aerodynamic Losses (drag from the air over the body of the car and through the front radiator)
2. Tire Losses (aerodynamic and rolling drag from the tires)
3. Drivetrain Losses (Inverter, motor, gearbox, bearings)
4. Ancillary Losses (12V loads, cooling fans and pumps, lights, etc.)
Each of these loss components has very different characteristics and is affected in different ways by making real world changes to the vehicle.
1. Aerodynamic losses are almost entirely determined by driving speed. The other issue to keep in mind is that these losses are determined by relative wind speed over the vehicle — not necessarily the speed over the ground. So if you are driving into a 10 mph headwind, it is nearly the same as driving 10 mph faster from an aerodynamic loss point of view. As you can see from the graph, this can have a huge impact on overall Wh/mile with even very small changes in wind. It is also important to note that, because the loss is not linear with air speed over the car, you cannot “zero out” the effect of wind by driving in a closed loop course the way you can with elevation changes. Driving into the wind for 1 mile and then turning around to drive downwind for the same 1 mile (all at the same speed) will use more energy than driving the same speed with no wind over 2 miles. Even a direct crosswind will slightly increase forward moving aerodynamic losses due to its interaction with the body shape.
2. Tire losses are mainly determined by the weight of the vehicle and the rolling drag of the tires themselves. For the Roadster we have chosen tires that offer a great combination of low rolling resistance and traction or grip. The air pressure in the tires has a large effect on this rolling resistance, grip and the overall tire loss. Higher pressure gives lower rolling resistance but a harsher ride and degraded handling. The above modeling is done at 30/40 psi front/rear. You can expect about a +/- 10Wh/mile variation with a +/- 20% variation in tire pressure. Similarly, by reducing vehicle mass you see a proportional reduction in rolling loss. So if you reduce total mass by 1% then you would reduce rolling loss by about 1%. In the configuration above, 1% equals about 30 lbs. So it is good to make sure that you are not “accidentally” carrying extra weight in the trunk or elsewhere if you are trying to get the best range possible.
3. Drivetrain losses include those that the user doesn’t typically control: the efficiency of the motor controller, the motor itself, the gearbox and generally all losses in converting the DC electricity from the battery pack into useful torque at the wheels of the car. This is proportional to speed due to spinning losses in the gearbox and motor and also proportional to power output due to conversion losses in the various subsystems.
4. Ancillary losses are caused by all “other” electrical loads in the vehicle, particularly the 12V cooling blowers and pumps, the 12V radio, internal and external lighting, etc. For the modeling above, we assumed that there was not heating or air conditioning load, but if there were it would show up here. These losses are somewhat different than the others because they represent a roughly constant power draw on the vehicle regardless of speed, winds or elevation changes. Because of this, they cause the energy usage per mile to start becoming high again at very low speeds. This effect would be even more pronounced if the heater or A/C system were operating. Likewise, the impact of ancillary losses is extremely small at high speeds because the primary propulsion power is very high and these small power draws make a relatively tiny contribution.
Range:
Now that we have a better understanding of how much energy the Roadster uses per mile, the next question is how far can it go? The typical full capacity of a new battery pack when charged to 100% in maximum range mode and discharged steadily over 3 hours is about 55kWh. Using that number you can calculate an interesting driving range curve for various speeds.
While this graph shows that driving range greater than 300 miles should be possible, the conditions to do this are quite rare: steady-state driving at 30 mph (no stops or starts) for more than 10 hours! What is most relevant for real world driving and trip planning is how the range varies between perhaps 45 mph and 80 mph.
One clear driving “tip” to take away from this is if you are ever nervous about making it to a given destination: you will do much better to slow down instead of speeding up. I’ve talked with many people who intuitively think that minimizing time to the destination will also minimize the energy usage, but just the opposite it true!
As you have probably seen from the discussion in this blog, many factors and assumptions affect range. The real world has wind, variations in road surface, hills, occasional stops and starts and other conditions. Given the complexity involved, I would be happy if a real-world test fell within about 10% of the modeled result for energy usage and range.
If you would like to “play” with these numbers yourself, below is a link to an Excel file with the table of data used to generate these graphs.
To our customers, happy driving. And we are always interested to hear back from you about other experiences with your Roadsters!
Best regards,
– JB
Download the excel data files here
Posted in the categories: Uncategorized
Great data!
Can you provide some consumption data for the headlights, radio, seat heaters, cabin heater, air conditioner, etc.? I understand that the heating/cooling components will have a variable duty cycle, but it has often been stated that using the seat heaters is “far” more efficient than heating the cabin. It would be interesting to analyze that. and the overall impact of accessories on range.
Excellent post for people to get their teeth into.
Hmm, I can’t see 55 miles on those graphs (ahem… Mr Clarkson)
Regen?
That is about what I expected, although range at top speed is slightly better than I would have predicted.
How much different is it with the top off and windows down, I wonder…
JB,
Thanks so much for posting this information! We appreciate the time you must have taken to present this information so clearly. This helps us understand how our cars will work and how to get the most out of driving them on the rare occasions when range is an issue.
Tom & Cathy Saxton
Thanks JB. Excellent post.
Don’t suppose we can have a graph for Model S?
A wonderful early gift for the holidays. Thanks JB!
For the endurance racing fans…
I thought it would be interesting to see how long you could drive (in hours) at a given constant speed.
This is just the range data divided by mph:
farm4.static.flickr.com/3231/3121261608_ce97d37f5d_o.jpg
Slightly zoomed in:
farm4.static.flickr.com/3095/3120433823_f87a1ffa40_o.jpg
About Clarkson’s 55 miles, I’m not defending him, but these graphs are from steady-speed data points. On the track, they accelerate hard (which of course uses more energy than gradually accelerating, and far more than steady-speed driving, even at 120 MPH.) They also brake very hard, likely hard enough that regen is maxed and they’re using friction brakes, so energy is wasted there. (Though the above graphs wouldn’t take regen into account at all if they’re steady-speed.)
So what would be interesting to see is a worst-case range figure achieved by flooring it to max speed, then braking as hard as possible to stop, and repeating until the battery is depleted (preferably on a wind-free day.)
Any owners willing to give us this figure?
Excellent blog! Excellent! This is something that should go to the FAQ on this site.
I think worst case would be to drive full throttle to the 125mph and then brake as hard as you can until car stops and repeat. With that you should be using approx 185kW power all of time (engine max) which would render car battery empty in roughly 20 minutes. You don’t get far in 20 minutes driving that style. IIRC Roadster got 12s time in 1/4 mile and end speed was somewhere near 120mph.
Calculating from that you get 1 mile in 48 secs. So 20 minutes would be 25 miles.
You would probably also have overheated engine, broken brakes, and some gray hairs.
JB, thank you very much for this data. It goes a long way toward putting my mind at ease. My experiments were consistently getting 6-10% worse results than expected and I was beginning to think there might be a problem with my car. But perhaps my discrepancy can be explained by a combination of having the lights and stereo on, possible light winds, slightly under-inflated tires, and the turn-around in the middle of my test. Each of those factors individually are pretty small but it’s possible they might add up. And I’m (barely) within your 10% confidence level anyway.
Now when can we have those nano-silicon batteries with 10x the energy density and stop worrying about these details
Sean, I think your test regime is beyond the capabilities of the car. You’ll reach thermal limits and the controller will reduce power. This apparently happened to Clarkson. And the worst part is I’m sure the engineers briefed them on the car’s operating limits but they chose to ignore them and then play them off as failures. For example, “boo hoo! charging from a 13A 110V socket takes sooooo long!!” Shame, Mr. Clarkson! But I agree, the 55 mile range is understandable given a “track day”. As far as I know the car’s top speed is not drag-limited. Meaning, it’s capped electronically and therefore you can consume a lot more power per mile for max acceleration than you will with max speed.
This solves my service trips problem from Phoenix to LA! I simply have to lose 50 pounds, wait for a windless day and drive 20 mph for 20 hours!
I think this is ‘pretty’ crucial data in order to understand the tesla roadster, I assume you educate your costumers with such data on their purchase?
Anyway, 2 important factors that are excluded from this blog is Lit-Ion capacity degradation and how it avoids being deep-cycled Is the recommended 75% capacity to 5%? That’s 70% of any given range on the chart. Also the thing that seems appealing is that after 5 years, better batteries have come out and you can actually upgrade your roadster, giving it more range. This kind of scaling is completely new in the automotive business
Keep doing what you do best tesla! Shedding the image of EVs as toy cars. You singlehandedly re-started EVs development.
Previous talk about making a hybrid roadster have suggested that it would need a motor almost the size of an original Elise, but I’ve been wondering about if it would be possible to make a hybrid Roadster using a small gas turbine from the aero industry.
This generates 12.5 Kw and weighs 24Kg, which is not a huge amount of extra weight:
cgi.ebay.co.uk/Lucas-Aerospace-Generator-200V-400Hz-12-5kW-Gas-Turbine_W0QQitemZ280292867990QQcmdZViewItemQQptZUK_CPV_Aviation_SM
According to the figures above, it would keep the roadster going at 55mph if the battery was completely dead. I imagine the overall package would probably be no better than a conventional gasoline setup, but this is only intended for emergencies or especially long journeys. Ideally you wouldn’t need to carry the generator on journeys when you didn’t need it, but it would require some sort of exhaust and air intake modifications to wherever you fit it in the car.
I would expect that there will also be some variation from car to car. Although Tesla surely maintains tight tolerances in the manufacture of critical parts, even very slight changes in areas such as the magnetic gap inside the motor and mating of the gears will create some significant differences between two otherwise identical cars. The batteries will also vary slightly, although using so many you would think that they would average out. Even the tires will vary slightly from batch to batch. The numbers may also change a bit after each car goes through some number of break-in miles.
Any predictions from Tesla on how big these accumulated differences might be? One percent? Ten percent?
Please note, Nubo, that Clarkson was in the UK. Therefore the wall plug he was using was 13A, 240V (50Hz). Oh, and the top speed is limited by the maximum RPM of the motor, but is electronically limited under that (Around 80-90% IIRC) to prevent issues of wear on the motor and drivetrain.
Nice to see so good informations. Very good blog.
Topic: New product idea.
Category: Battery charger
Problem: Looking at nice and slick car, i just do not see big electrical cable for charging battery being “sexy”.
Solution: Design math that you will put on the floor in the garage, drive car over it (park) and wirelessly transfer energy for battery charging.
Note: if you have any additional questions, please do not hesitate to contact me.
Transmission—not a change for the Roadster—but for the “S”.
The transmission on the power/speed/usage curves seem to be telling that it can’t get out of its own way at high speeds. The gear ratio is meant to blast the Roadster out of the gate to hit 60mph, without blowing the transmission up—(2 gear old tranny).
One reason the old 2 speed blew up was the bone crushing force that was hitting all parts of the transmission from the electric motor while “speed shifting”.
Hey—remember all the “slop” you have with a “normal” car’s shifts—depress the clutch, drop rpms, clutch—throwout bearing–flywheel—shift the gear–let out the clutch–all this is “easy” on a transmission. Now, if you do it hard—popping the clutch, etc all the time, well your clutch will probably be the 1st to die—but the tranny isn’t far behind.
So for the model S—play with the gear ratio and talk to some tranny peeps who are experts with Overdrives. One other solution is to have a multi speed tranny but not allow shifting….crazy?….no you select the gear before you start and you are “locked in” untill you come to a stop and put it in park.
Think of the new tranny as multi power vs multi speed.
Power 1–High Power … lower range for blasting down the road or getting out of a dangerous area.
Power 2–Med Power … everyday cruising at 55-80 mph give you good range and still high speed.
Power 3–Extended Range…Sunday Driving—30-60 mph smooth terrain.
And the most scary idea of all—an automatic tranny w/overdrive… CVT?
Engineering question: So…the idea is to use the car to run 20 minute sprints on a road course; Given that you need to modify the suspension, add racing tires, etc. How much of the battery would you be able to remove if you ran 2 minute laps and swapped out the battery between sessions? What would be the tech weight of the car with this reduced battery weight?
I see that your tire pressures are 30/40 front to back; what is the front to back weight ratio and what would it be with the reduced battery load?
I watched the TG presentation and was not impressed with the comments by the host. You car has proven what it set out to prove…simply that electric cars are viable for everyday usage.
Interesting point about a gas turbine hybrid. But I don’t think that’s the right answer for long trips. The right answer is medium-fast charging (say 1 hour for 200 miles worth of charge). Think about the cost of the two approaches. The design work for making a hybrid is at least several million dollars. The design work for a medium-fast charger is essentially zero. The cost of producing the extra mechanical bits for a hybrid is several thousand dollars each. Which is about the same as the cost of one charging station with installation. So suppose you’re going to have 2000 vehicles. In the hybrid case you have a (low-ball estimate) of $1000 per car for the design plus $2000 for the parts. That’s $6 million. If the charging stations can be installed for $3000 each (parts and labor) then you can have 2000 of them for the same $6 million. 2000 charging stations would easily cover the entire USA. And as the number of cars increases the tradeoff becomes even more favorable. After a while, you’ll need more charging stations or ones that can support several cars at once. But that’s still much cheaper than paying for the hybrids.
JB, can you say anything about the possible use of the newer 18650 cells that are coming onto the market - i.e. Panasonic’s 2900mAh which are used in the Asus eePC or their previously announced 3600mAh cells?
Have you modelled their use in the car? Do you know if they are able to support the charge and discharge rates or lifetimes needed in the Roadster? It would be fantastic if the 3600mAh cells could boost the car’s EPA range to around 400 miles, but I’m sure it isn’t a simple swap.
Thanks, JB. Very informative … and appreciated.
BillB and Roger Richardson bring up three variables I am also interested in.
a] Assume an additional 150lb passenger.
b] You mentioned headlights being a large 12V load. How much ? And is there an improvement in the works (LEDs) ?
c] Seat versus cabin heater.
Thanks.
errr …… driving like a Top Gear presenter clearly does put you near the 55 miles range, as it happened! Real world driving its not, but the occasional ’spurt’ built in to a days driving would be more realistic. What we need is the engine management memorising all of its driving data and downloading it to a central server so as to determine a true set of mean values. Surely being stationary is only a drain when its dark and winter?
The generator you list is just the generator (mechanical -> electrical), not the gas turbine to drive it, fuel tank etc.
Robert Munro,
you realise that generator you linked to is the generator (alternator) only?
despite the listing, it is only 12.5kva, at PF 0.8, so only 10kw avail.
it doesnt include the prime mover.
the funnel at the front is for cooling air for the windings, since most APUs are in enclosed spaces.
gas turbines are only efficient when run for at least 10x their heat up time.
the amount of gas required for the 4 or 5 hrs this would require is enormous, and heavy.
Matt
So now, not only do I need the cruise control to work down to 25mph for city streets, I need it to go down to 17mph so I can drive 400 miles.
I have not seen the specs for the high power plug what makes this charge in only 3.5 hours ? what kinda load would
this put on a power grid compared to a 240v 13 amp plug ? and how long is the charge time from a 13 amp plug ?
why is the high power charger not mentioned anywhere i can find in the specs or the faqs ?
what about solar charging ? how long would charging from 12-18 volt panels take ? and at what amperage ?
would you have to wire up tons of series panels to use this realistic and not get weeks of chargetime ?
is there an input in the car for charging with lower voltages like 12 v ? (or would one have to dissect the batteries
to get to the modules directly ?) i guess a dc-dc charger for any voltage would be useful to match the load
what if the dc-dc power / high voltage power in the battery burns out ? thats the most likely unit to fail, would that toast the whole battery pack or is it an easy swap to replace this ? also using 2 fuses pr cells seems like a waste of money and weight.
why not use one fuse pr tube of cells ? if a cell opens and fails you will lose a whole tube anyway and if the
cells burn up in the tube it will hardly have any safety issues i see. worst case it will cool down in minutes
no way a short can do serious damage unless a whole module is shorted out. 3-4 cells carry rather limited juice
that never could damage adjacent tubes/cell packs
shorts in the dc-dc powers/diodes is the only real issue i see with the battery system which would blow out the fuse
for a whole module, hopefully that can be replaced easy ? also is there an easy replacement if a tube/cell goes ? im hoping
this is not a costly repair ? seems to me its simple to yank out a tube of cells and replace it rather than buy a costly new
battery pack ? how many cells would be lost if a cell opens ? to me a design plus would be easy to change dc-dc
powers and fuses for the module packs without having to dissect the whole pack.
also what is the cost of the battery since it needs replacing every few years ?
the graph shows clearly why the top gear presenter only gets 55 miles or so that seems to match pretty good
with the hard accelleration and max constant speed which will surely burn tons of juice.
what are the actual figures for more regular average driving ? (few people run 125 mph constant i guess)
any drivers that can share their average mileage ? also list if its city driving or freeway or other type as the patterns
will be very different
JB,
May I know more about the motor of this vehicle?
I don’t want any of your secrets, but something about the type of the motor.
As I know it is a DC motor.
But do you use permanent magnets?
Because the universal motor don’t.
I need to know this.
Important!
Because this car is really impressive!
I want to know more about it…interesting creature…really is!
Please support me for a little more info…Please!!!
Sandor
Thanks for the honesty of the information provided. It is rare to see a manufacturer who has the guts to deal in facts and to handle the head-on.
Constructive criticism is great, but too many good ideas and products are shot down by critics who miss the point and focus on negatives.
Perhaps the question which should be asked is what percentage of the population travels less than, say 120 miles a day? And that becomes your target market as those people will probably be very happy to use a vehicle with such low- cost per mile and a much lower environmental. (And they will probably be able to drive the 120 miles with headlights, air-con, roof down, wrong tire pressure and in rush hour).
When I look at the Tesla, I see much more pros than cons. Keep up the great work and focus on the positives as that is the formula to success and ‘Never, never ever give up’ (Sir Winstoin Chuirchill)
Hi Guys,
I watched your Tesla roadster perform on the Top Gear show here in the UK. Performed well but reliability issues and loss of charge versus time to recharge were badly slated by Jermey Clarkson.
Just read today that Toshiba are setting up new plant to produce a new generation battery which seems to answer all the issues and drawbacks of your current set up.
Are you already getting to grips with this and when can you get a re run on Top Gear with it?
FYI
This looks like a possible breakthrough in battery technology and likey to a have major impact in the next few years.
newsvote.bbc.co.uk/1/hi/business/7798637.stm
www3.toshiba.co.jp/sic/english/scib/index3.htm
Elliott from Perth Scotland
I run a Daihatsu Copen (660cc turbo charged roadster)
When electricity is cheap, clean and abundant, and when batteries / capacitors / hydrogen is/are cheap, light, small and rapidly rechargeable, no one will care about efficiency. They will only care about styling and utility. I look forward to seeing the exotic vehicles that will appear after we’ve fully converted to renewable sources of energy.
Robert Johnston - thanks for the correction; I didn’t sanity-check my own numbers. But it seems likely if Jeremy actually had a 120V service he would have used *that*. Obviously most Tesla owners will avail themselves of a more utilitarian charge rate. Top Gear’s dishonesty lies in presenting a 16 hour charge as something you’re simply stuck with. Unless there are other aspects of electrical service in the UK that preclude a homeowner from being able to provision a 240×70 or even a 240×40 connection? Of course, they had to make their point even more blatant by creating a the straw-man of charging the Tesla with a small windmill. I guess they edited out the part of the Clarity segment where they obtained Hydrogen via Hamster wheel-powered hydrolysis.
I would have thought that the best way to enable long distance touring in the Roadster and Model S is to design a REEV (Range Extended Electric Vehicle) trailer. This would be a trailer with a small (Smat Car?) engine and fuel tank attached to a generator with a special trailer plug that talks directly to the PEM. If you used a flat 4 (Subaru?) motor you could even have extra luggage space on top.
You could hire this from Tesla when you wanted to go touring and place your roadster into a 4′th mode REEV. The ICE would then turn on at a pre-determined battery level and top-you-up as you drive giving almost a whole day of highway cruising.
Has Tesla Motors considered this?
JB-
From one engineer to another - thanks, very concise presentation of the data. Very thoughtful and elegant engineering work - you’ve designed a beautiful product. I understand our governor has purchased one also… My only question is…how does he fit into one of these…???
Kurt S
Why hasn’t anyone developed a generator using the rear end axal housing to contain the system? This could be a long (length) generating system that would use the movement of the wheels to generate electricity; feed to the main batteries, and if need be you could also generate electricity off the front wheels around the disc brake system. Presently these are concepts; but doable. Just braingas with some possibilities.
As Chief Technology Officer, maybe you could influence your Marketing Dept. to remove the misleading statement that the
Tesla Roadster “Burns no Oil”. Most of the electricity in the US is generated by coal, a major polluter. In California, 60% is generated by natural
gas, which contributes to atmospheric carbon dioxide at a higher rate than coal. Of the natural gas burned to make electricity, a substantial
portion is made from oil, which makes the statement no only misleading, but false. It is possible that, when the entire energy generation and manufacturing
chain is considered, the electric car consumes more oil than a conventional car in the same class, and pollutes more.
I think it is important to prevent spreading myths among consumers that driving an electric car is somehow more righteous than driving a conventional
car, simply because it doesn’t have a tailpipe.
- Dave
www.epa.gov/climatechange/emissions/co2_human.html
www.epa.gov/climatechange/emissions/co2_human.html
This topic of range, and people’s reactions to it (in this and other forums), is really fascinating. We have a Maxima and a Quest van. My max has 143K on it and i the past few years I have taken maybe 4 trips longer than 200 miles in it. The van is newer - maybe 45K on it - and we have taken 4 or 5 trips in it as well. So the question is “would I be willing to rent a car for those 8 or 9 trips in order to have a ZEV for all other driving situations?” The answer is absolutely, undoubtedly, resoundingly YES. That is such a small price to pay that it is hardly even a factor in my decision making process. As for range during aggressive driving, an EV performs exactly like a gas-powered car: if you rag on it, your mileage is worse. This has been the same since the invention of the ICE, but all of the sudden it’s a big deal? An EV isn’t for everyone. Complaining about these shortcomings is like complaining about the trunk space of a Lamborghini or the skid pad rating of a suburban.
Hi:
The Tesla White Paper on CO2 Efficiency was an important paper. It has been removed from the website and not updated. When will it be made available again? I can’t tell how long ago it was removed, as the removal was not dated.
Josh
hi there
i have not seen the TG program on the Tesla but i did see the one with the Ford GT that Clockson actually bought, i think that had a range of about 75 miles on the test track, surely 55 miles (73% of the Fords range) from the Tesla is outstanding and only helps to confirm its viability as a performance electric car.
Top Gear BBC1 did an electric car special with the Tesla and and Honda FCX hydrogen car. The Tesla, despite having a 125mph top speed went round their test track faster than a Porsche 911 GT3 RS (996). The team did not like it however because as your own site states: 3.5 hours recharge time from flat. The Honda they did love as it is hydrogen and therefore fills in seconds at a pump. The weight of your car is mostly batteries. If you were to reduce your batteries by a factor of 10 or even 50 and using a hydrogen fuel cell to constantly recharge the batteries then not only would you have all the advantages of the Honda but your car would also be massively lighter and would be competing with the very fastest cars on planet earth. Just a thought.
Dave Fisher, Tesla Roadster does not burn oil. Generating electricity **might** burn oil, and manufacturing some parts might, but car itself doesn’t. So it is not false to say that Roadster does not burn oil.
Additionally even if we just plain start burning gasoline in power plants generated electricity would be cleaner than burning that same gasoline in cars. Even with using **only** coal to produce electricity and then drive EV with it would be cleaner than any gas engine car.
Electricity can be produced completely without oil, and soon it will. Nuclear, hydro, wind, geothermal and solar are all clean sources of electricity. In fact there is no other reason to use fossil fuels than that those are cheaper then renewable sources. Geothermal alone has potential for several thousand times world energy need, and solar is potentially practically infinite.
Please get your facts straight before making this claim again.
Patrick, generating hydrogen requires enormous amount of electricity,about factor of two more than what battery electric vehicles would use. Also hydrogen is extremely poor method of transporting energy because hydrogen leaks out from any container (hydrogen molecyle is basically just two protons surrounded by two electrons, so if that molecyle loses those electrons those protons go just straight thru any material), it compresses badly and itis extremely explosive.
One thing that TG didn’t mention was that Honda FCX costs several **milion** dollars just to produce (you can’t buy one), so compared to that Roadster is cheap car.
There also is no hydrogen stations, while you can recharhge your Roadster at home or from any outlet out there. Charging time doesn’t really matter if you charge your car duringnnight while you sleep. Batteries also are developing fast. With near future 600+ mile range BEV are real future. I don’t think this hydrogen future will ever happen.
Elliot Boyle, those Toshiba batteries have very poor energy density, so they would be useless to electric cars, but batteries do advance and fast. If you have some university access Sciencedirect Journal of Power Sources is great place to read what is happenng in battery tech. 450Wh/kg prototype battery has been already made (LiFePO4 cathode, Si anode battery), and that isn’t best potential battery I have seen.
I was interested to look at top gear testing the tesla, but was disappointed that he was untruthful about the cars ability. I feel that they have a vested interest in seeing the electric car fail and will do anything to scupper the rise of the electric car. They do not have any vision. We know that electric cars have to be the future and the Tesla is a very exciting innovative leap forward.
Keep going - I am looking forward to the day I can afford one!!!!
Re: “Burning no oil”
Dave you seem hell bent on getting Tesla to change the wording of their statement that “It burns no oil.” I don’t understand your beef?
Many purchasers of the Roadster are also buying the solar panel kit that is available and - over the course of a year - that will mean that they will purchase no electricity (for charging the vehicle). Some have already said that they are actually selling power back to the electric companies.
Of course you could REALLY stretch it and point out that polymers come from coal and/or oil so Tesla is again guilty of false statements because of the materials from which their vehicle is made.
Or there again you could just accept that “Burns no oil” is not just a figure of speech and is simply a regurgitated old chestnut.
Peter J Hedge
Victoria,
BC
About TopGear 55 miles range claim :
1. Presented data about drivetrain losses make it possible to compute overall battery to wheel energy efficiensy. It changes from 62% at 40 mph to 71% at 80 mph to 76% at 120 mph. All these numbers are significantly lower than 80% efficiensy vaguely claimed for Tesla Roadster in the early days of development.
Assuming regenerative braking has same efficiensy as acceleration overall acceleration/deseleration energy retrun would be 40% to 50%.
2. Presented range is steady state - no acceleration/deseleration cycles. In case if TopGear raced with acceleration/deseleration between 60 mph and 120 mph every about 300 meters (5 to 6 times per mile) based on 50% regeneration efficiensy and steady state range close to 110 miles (102 mph) resulted range would be close to 55 miles.
So TopGear folks might actually get the 55 miles range they claim in real life by driving like described with a lot of turns and close to top speed. Based on the video they demonstrate that mode of operation is the only thing they care. Gasoline cars in such a mode do not suffer that much because they have higher range in general and could be refueled rapidly.
Unfortunately battery EV are not race cars from a range point of view. So Tesla Roadster is hardly a good race track car. On the other hand for fairly steady driving in the range 40 mph to 80 mph even with twisting road the car would demonstrate decent range. I guess the whole TopGear evaluation was badly focused from the car use model point of view expected for Tesla roadster most of the time.
Sandor: The Tesla Roadster uses a 3 phase induction motor www.teslamotors.com/blog4/?p=45 www.teslamotors.com/blog4/?p=67
Kristian Solstad wrote on December 23rd, 2008 at 2:02 am
I have not seen the specs for the high power plug what makes this charge in only 3.5 hours ? what kinda load would
this put on a power grid compared to a 240v 13 amp plug ? and how long is the charge time from a 13 amp plug ?
Tesla charger is 75A at 230V so 13A would take 3.5hrs * 75/13 = 20 hrs.
why is the high power charger not mentioned anywhere i can find in the specs or the faqs ?
Can’t answer that.
what about solar charging ? how long would charging from 12-18 volt panels take ? and at what amperage ?
forever.
would you have to wire up tons of series panels to use this realistic and not get weeks of chargetime ?
yes. you want about 10kw of panels.
see the white paper about batteries www.teslamotors.com/blog4/?p=59
Two fuses does seem extravagant, but they are different types and one comes built into the battery.
They are wired in parallel, not series in a tube. This is so if one fails, then it has minimal impact on overall performance. You are correct that if they were in a tube, series wired, one failure would make the whole tube useless. A lot of work has gone into the design to make it safe and robust.
# Lad wrote on December 20th, 2008 at 10:51 pm
## I see that your tire pressures are 30/40 front to back; what is the front to back weight ratio
I have read that it is 35% front, 65% rear.
# Sandor wrote on December 23rd, 2008 at 5:28 pm
## May I know more about the motor of this vehicle?
## As I know it is a DC motor. But do you use permanent magnets?
No, it is an AC induction motor with no permanent magnets.
## Mark Melocco wrote on December 24th, 2008 at 4:53 pm
## I would have thought that the best way to enable long distance touring in the Roadster and Model S is to design a REEV (Range Extended Electric Vehicle) trailer.
## This would be a trailer with a small engine and fuel tank attached to a generator with a special trailer plug that talks directly to the PEM.
## You could hire this from Tesla when you wanted to go touring and place your roadster into a 4′th mode REEV.
## The ICE would then turn on at a pre-determined battery level and top-you-up as you drive giving almost a whole day of highway cruising.
## Has Tesla Motors considered this?
Their CTO has built such things before. As far as I know Tesla plans to be BEV only and stay away from anything gas powered.
(Good decision IMHO)
Anatoly, you said that battery EV:s are not race cars. I say that they can be. It is only matter of how fast you can “recharge” your car. F1 fuels in about five seconds. You could make high energy density swappable primary battey pack for EV that does the same. Or you could use battery to battery charging, but then you couldn’t “recharge” quite that fast.
Question: how often does diesel-powered car goes to pitstop in Le Mans 24h race and how long does one stop take? I bet we could create EV that gets similar result as some Porsche using battery to battery charging. If not yet, then soon.
There is an awful lot of people coming up with a lot of great ideas in regard to extending the battery life. Some are trailers, an extra small engine, etc. The tesla is already using divises to cool the batteries. By opening a small port in the front of the Tesla, and inserting a small squirel cage air driven divise, you can divert some of the kinetic energy that blows against the car and direct it to run a small alternator that would feed current back into the battery system, thus easily recharge the and extend the daily life of the batteries as you go.
Another way you could do it, is to hook it to a wheel using a small drive shaft that would spin the alternator. I think the wind idea is better because you divert energy from the force of air against the front of the car and direct it downward through the squirel cage, and out below the vehicle.
The other thing you could do is to use the downward force of inertia when you are going down hill to generate power back to the batteries, instead of having to break as much, kind of like regenerative brakeing, but it would be on all the time the car is coasting on its own inertia.
I would like to know why this type of system would not work, and extend the driving time for the Tesla owners.
A VERY HAPPY & PROSPEROUS YEAR TO EVERYONE AT TESLA MOTORS!!!!!!!
I am hoping the new Prez. & the new year will be beneficial for Tesla…
With reference to this post:
Jason M. Hendler wrote on December 24th, 2008 at 11:55 am
“When electricity is cheap, clean and abundant, and when batteries / capacitors / hydrogen is/are cheap, light, small and rapidly rechargeable, no one will care about efficiency. They will only care about styling and utility. I look forward to seeing the exotic vehicles that will appear after we’ve fully converted to renewable sources of energy.”
I’d like to point out that, despite how much a curmudgeon I must sound on this forum, I am an inveterate gadget head. I love imagining exotic technology. Experiments with electric cars should continue. I expect real benefits will come from that.
Somebody on this blog praised Tesla for their honesty. While we’re on the subject, guess what, I’ve owned a Prius for 3 years. However, I have no illusions that I’m rescuing the planet, except to the extent that driving a lighter, medium power car can help. I like very much not having to go to the gas pump as often. I am aware that the CO2 coming out my tailpipe, and generated in the manufacture and supply process, are not insignificant, and may actually add up to more than that for a conventional car. I have an idea that driving hybrid cars may help us prove, or disprove the concepts behind it’s design.
In our righteous zeal to save the world, we should avoid creating illusions. I am dubious that electric car experiments should be closely tied to marketing strategies. We should help educate the consumer about the complexity of the problem, instead of proclaiming that 2009 will be “The Year of the Electric Car” (New Yorl Times ?), for example.
The proverbial cart is before the horse, in my opinion. We should PROVE that batteries can be made cheaply. What will happen to the cost of them as more and more people are driving electric cars.
As the relatively scarce raw materials, used to manufacture the batteries, come under higher and higher demand, the price of the battery will increase rapidly. We talk about Peak Oil. How far off is Peak Cadmium, for instance? Further, has it been proven that enough hydroelectric dams, windmills, nuclear power plants, and other sources of “renewable energy”, will ever satisfy demand for electricity to power the new world of electric cars?
Attempting to solve these problems with technology is very exciting. It is inspiring to see what can be done, and dream about what might be done. Perhaps electric car experiments should proceed in parallel with development of renewable energy sources and reduction of greenhouse gasses.
Mr Hendler, do you really want people to stop thinking about efficiency, and focus simply on styling and utility? I’m all for creation of genuinely renewable energy sources, as long as that goes hand in hand with creation of a carbon neutral atmosphere, following a massive reduction of atmospheric carbon. Seems a long ways off to me, but still worth pursuing.
Recall the excitement over the apparent discovery of cold fusion? Until an energy perpetual motion machine is invented, we should obsess ourselves with energy efficiency, in both the local and global context.
- Dave
I wrote to Elon just before Christmas, by post, awaiting reply. I have been looking at increased mileage from a different point of view. If my idea works I think it will advance electric cars dramatically. I believe that Porsche are trialling an electric 911 but the batteries and weight are enormous. I did not say too much in my letter because if it is useful then I think the Tesla would be the ideal development because of its power. On the other hand if it doesn’t work it is just another idea for the bin.
I live in London and I feel that it would sell well here.
This is probably not blog material.
Dave,
I do want people to stop obsessing about efficiency, to the point where most every sedan looks alike. I literally cannot tell the difference between some American, European and Japanese sedans. Much of that is due to copy-catting styling cues, as opposed to aerodynamic optimization, but aerodynamic optimization is, bar far, the most style limiting parameter, which is driven by efficiency / mileage targets.
As I stated, when transportation energy techs allow clean, renewable, cheap and abundant energy, I DO want to see great variations in vehicle design - some retro, some futuristic, etc. I want to see many, many different styles and utilities in vehicle design.
Dave, you again make that false claim that BEV CO2 “manufacturing and supply process…might add up more than conventional car”. it DOES NOT. Not even close. That is very very far from true. Conventional car causes several times more pollution than BEV INCLUDING manufacturing and supply process.
So I again urge you to get your facts right before making this claim again.
You also make funny claim that renewable energy sources might not be enough for BEV:s. That is just plain silly. Like I wrote earlier geothermal alone has potential for several THOUSAND times world current use of electricity. Solar is even greater source. Only reason to stay in fossil fuels is that those are cheap.
What happens to battery prices? Well, only really rare material is lithium itself, and that is recycleable and there are way more than enough of it for world battery need, also batteries develop so where now you need to use x amount of materials you soon need x/5 amount of material. Then you only need manufacturing plants. So,yes, their prices will go down.
Even with batteries current prices you win compared to gas during car life cycle.
One question, Dave: which gas company gives you money for distributing these plain wrong informations?
To Timo :
Sure if somebody figures out how to swap heavy battery pack in EV such cars could be managed as nice race cars. I guess A123 kind of battery (high power) battery should be used or similar style. You will need 3 to 5 battery packs so that while one of them is in the car others are under charging.
For A123 or similar 10C, ~80 Wh / kg type battery we one could have say ~400 kg pack so that we have ~30 kWh with steady power up to ~300 kW. That would manage I guess ~15 min of racing with average ~120 kW and speed between 100 to 200 mph. If battery packs could be swapped in 10-20 sec that would manage decent racing periods. Having enough packs charging in parallel would match changing time under 15 min so that battery packs could be swapped without delays. Having several thousand recharge cycles would help to keep battery packs alive for decent time under such heavy recharging conditions.
Some issue exist how to manage swapping heavy battery packs fast but keeping structural integrity of the car under heavy accelerations. I guess it could be solved although would be a challenge.
But EV has inherent advantage of steady high torwue without gear switching. So likely it would beat gasoline cars in racing even with battery swapping time losses.
Just this is not the Tesla roadster design - that is all.
This document:
www.ferdinand-motor.no/images/tesla/EuroSpec.pdf
says:
“Motor 3-phase, 4-pole electric motor, 300+ bhp peak (225+kW)…”
Is this 300+bhp/225+kW figure correct for US spec roadsters also?
%TEG:
Thank you for the information. With a front to back ratio of 35/65, the cornering forces will tend to make the car over steer and that might explain why the car didn’t do as well as I thought it would on the video timed lap. I’m sure the suspension is engineered well for driving on the streets and should be great fun to drive there.
Congratulations to CJ & the team
I am nearing 65 & live in Johannesburg, South Africa. For as long as I can remember I have dreamed that one day a competitive
battery driven vehicle would be built.
You guys have made my dreams & others become a reallity. What you have achieved is fantastic. The lines are just beautiful, the technology cutting edge, something all enthusiasts will be proud of.
Keep up the good work, forget the nay-sayers, you are the future
Ray Bailey
Why measure watt/hrs per mile?
Miles per watt/hr is much more intuitive (at least to me) because its closer to “MPG(miles per gallon)”, and defines vehicle range ultimately by battery capacity.
To Timo, who asked me:
” which gas company gives you money for distributing these plain wrong informations?”
Gas companies BAD. Electric car companies GOOD.
I thought it was clear that I am speculating, hence I say: “manufacturing and supply process…might add up more than conventional car”. “might”
Far from offering facts (I’m not an expert on any of this), rather I am trying to encourage sober thought and careful research before jumping on the bandwagon.
You seem to be offering as absolute fact that the electric pollutes far less than the conventional car. You may be right. I’ve heard arguments of both sides of the electric vs internal combustion argument. In the controversy over whether the Hummer is actually less polluting than the Prius, “dust to dust”, computer models predict the Prius should pollute less than the Hummer. It would be interesting to see what the prediction would be comparing the Prius with a gas-efficient conventional car in the same weight class. EPA rated the Prius at 55 MpG. Consumer Reports says the Prius figures are 20% higher than actual. In fact I’ve never gotten more than 45 MpG. The VW Golf gets 38 MpG, not too far behind. Should we dismiss the possibility conventional cars can be made just as low polluting as electrics, just because they have a tailpipe?
No question the electric car gets better mileage. However, the burden of proof is on the engineers, manufacturers, electric power companies and battery recyclers, that electric cars will significantly reduce greenhouse gasses globally.
It seems the electric car was killed by the combined forces of big oil, Detroit and deregulation, involving deceit and misleading marketing. Those forces see “Burns no Gas” as an affront. If threatened, they might try to tear apart such a statement, and could easily do so. They are grand masters of marketing. Don’t hand them the opportunity. Do more than just figure out how to sell an electric car to the conventional consumer interested in protecting the environment. Present irrefutable facts based on actual data. Now there’s an innovative marketing strategy!
- Dave
Todd, I guess it is just matter of what are you doing:
53kWh battery pack, 240 mile range = 53000/240 = 220 Wh/mile == 240/53 = 4.5 miles/kWh.
First case shows directly how much power car is using per mile, so it is better determining how big battery pack you need for certain goal range, latter shows more directly how far you get with fixed size battery pack (assuming that multiplying is easier than dividing for normal human being).
when will you guys be in the East Coast?
Dave, Prius is a non-efficient parallel hybrid car. It has usual extremely low efficiency gas engine, so it doesn’t surprise me that you get bad result from that. Pure BEV is entirely different beast. I assume your Prius is a model where you can drive with electric engine alone, right? If you are driving with electric only, how many MPGs do you then get?
It all goes back to efficiency. Which is more efficient, generating electricity in power plant and then run that electricity in ~80% efficiently in EV or burn fossil fuel in gasoline car with very low efficiency + refining process losses? Fact is that conventional car engine is very bad in turning combustion to kinetic energy.
If you then add to that calculation that electricity can be produced entirely free from fossil fuels then BEV pollution isn’t even close to traditional gasoline engine. You can even generate that electricity yourself by wind, water or solar systems, no need for big companies assuming you live in place you can access those resources. If you do then your MPG is actually infinite, because you get some miles but you burn zero gallons of gas, and as everybody knows anything bigger than zero divided by zero is infinite. There are countries in this world right now that don’t use fossil fuels at all for their electricity needs because they have geothermal or water resources for them. There is no reason why US should be any different.
You have 500+ billion military budged. Cut that to half (who is attacking you? Canada? Mexico?) and use that 250 billion for geothermal and solar power plant development and production, get everybody their own Roadster or Type S or Electric Porsche and your entire country would be free from foreign oil in no time. If you do that you also cut down money flow to middle-east and by side-effect cut down terrorist money sources.
What comes to “manufacturing process” pollution, EV engine is less complex and batteries can be recycled. No more pollution there, less would be my guess. Transportation or “supply process” as you name it is obviously less polluting (electricity is transported by wire, wires do no pollute).
You did also earlier talk about “relatively scare raw materials” in batteries. LiFePO4 - Silicon battery would be consisted from Lithium (relatively rare, but more than enough is around, as it can be recycled and doesn’t disappear anywhere in batteries), Iron (very common), Phosporous (is used as fertilizer, common), Oxygen (most common element in the crust) and Silicon (second most common element in the crust).
You simply did have pretty much all your “facts” or claims wrong so badly that it felt like trolling. If you did not try to spread misinformation and you are just curious if BEV is greener than conventional car then I urge you to read some more or just believe that BEV is greener than conventional car.
To answer my own question about MPG vs GPM is this site, which states the case for
measuring gallons/fuel per X miles to compare vehicles
www.mpgillusion.com/
Apparently, stating consumption this way makes it clear that removing inefficient vehicles is
much more effective than improving efficiency in overall energy usage (hence the illusion).
Thanks for publishing the information J B . Is the 55Kwh figure that you quote the maximum output from the fully charged battery pack? and how does this drop off over the recharging cycles? Would the nanotech batteries which the Lightning company propose to use give a safer quick charge and better performance?
The BBC “Top Gear” programme ( you can tell I’m a Brit by the way I correctly spell programme ) was extremely unfair. I watched the programme after it had been broadcast because I had heard it being discussed. I did write to them and suggest that they read some of the papers which Prof Ulf Bossel has written on the subject of Hydrogen as synthetic fuel. I don’t think they researched their material very well before scripting the prog. I would not take it seriously but for the fact that most TV viewers sit on their brains and will not have subjected the statements to critical thought. The received ‘ wisdom’ they will have taken away from the programme is that cars which store their energy of propulsion in highly compressed explosive are the vehicle of the future whilst tried and tested accumulator storage is a dead end. The BBC is a public service broadcaster and not tied to sponsors in any way so tends to be trusted more than a commercially funded broadcaster. They should be more responsible and I shall probably write to them again if I fail to get a response. If you receive an apology from them will you please publish it on the website.
I liked the comment by Nubo on 24th Dec. about the Hamster-wheel. I have also read Rachel K’s response to the programme. She clarified a few points regarding the supposed 55 mile range and the ‘brake failure’ which wasn’t .
May I have a test drive in the UK? I could never afford a Roadster but I can dream.
Whatever the facts of EV versus Petrol/Diesel powered cars.We need to focus on the fact that oil might run out sooner than we think.So we are then faced with the dilemma of how we produce all of the other items that sustain our ever demanding lifestyles that are products of oil.
Can we think of any modern product that are not made or produced from oil !!!!!
Our life has been subsidised by oil for generations -Without oil this planet could not sustain the current population.
The arguments are not purely “Green” - they should be about conservation of a precious resource. it is interesting that the oil rich nations are building nuclear power plants -they know that one day it will run out and they are being prudent and building for the future.
What I am trying to say is that we need oil but lets give other technologies the investment that has been given to the I.C.E( internal combustion engined ) car manufacturers.
Governments are at last seeing the light and creating an environment where the gas guzzlers are taxed out of existence. Tesla have proven that it is possible to build a sports car that is fun to drive without consuming vast quantities of oil.
The other fact that is dis-regarded when folk go on about the oil being used to produce the electricity to charge E.V is that often the car batteries will be re-charged overnight on off- peak electricity as it used to be called.This is the electricity that is being produced regardless of demand when most people are asleep. I know that there will be people saying that this is ramped down at night tomatch demand but the generators are still running!
Let us embrace new technology -Those who don’t evolve end up extinct . Future generations will curse us for squandering all the oil reserves.
E.V’s are getting there and the I.C.E car manufacturers are worried and so they should be!
To Dave Fisher about EV efficiensy :
You are correct noticing that battery electric car still use electric energy mostly generated from fossil fuel. BUT you are missing at least following critically important facts :
1. Energy conversion efficiensy for electricity generation by stationary power plant is at least 50 % for most horrible coal plants and is 60 % in general. Energy efficiensy of charge/discharge of Li-ion batteries is at least 90 %. Energy efficiensy of electric transmission is easily 90 % and coule be made up to 97 %. Overall efficiensy from fossil fuel to mechanical energy coming to wheels would be 40 % worst case and 50 % average.
For comparison energy efficiensy of regular gasoline car engine is 20 % worst case and less than 30 % average. So here we have almost twice more efficient overall fossil fuel energy use for mechanical driving regardless that we have more complicated energy conversion.
2. Electric car has ability of regenerative braking. So if you reduce speed during driving or if you go downhill in electric vehicle you reuse at least 50 % of that energy back to driving. In fact up to 90 % of that energy could be reused back to driving with proper design. This is basically the only reason why hybrid cars has betetr mileage. For example Toyota Camry has 28 mpg EPA but Toyota Hybrid has about 40 mpg EPA. This difference characterises energy efficiensy improvement from regenerative braking.
Regular ICE cars (not hybrids) do not have described energy efficiensy improvement.
3. From CO2 emission point of view if you use coal you have 38 MJ / kg of carbon ( 3.67 kg of CO2 per 1 kg of carbon ) which generates 96 g of CO2 per every MJ of energy. For gasoline we have 45 MJ / kg of fuel ( 3.14 kg of CO2 per 1 kg of fuel ) making 69 g of CO2 per every MJ of energy. Comparing worst case electric case with 40 % overall efficiensy we get 240 g of CO2 per 1 MJ of wheels energy versus about the same mass of CO2 of regular gasoline car per same wheels energy.
But it is not fair to compare absolute worst case for electric car with absolute best case for gasoline car. In case if you take average for fossil fuels you get aboput twice less pollution from electric car because of twice less fossil fuel energy use coming to wheels for same driving.
4. Electricity could be generated from solar power or wind power which are practical and even business profitable technologies of electric generation today making no CO2 generation while operating. This makes electric cars better positioned for the future CO2 reduction compared to gasoline cars.
5. The only significant manufacturing difference between electric car and gasoline car is big battery pack. For Li-ion battery it includes carbon, lithium and cobalt oxide. It is hard to see how extraction of all these elements would generate any dramatic amount of extra CO2 pollution. Materials of such batteries are not consumed by its aging. So with proper recycle of electric vehicle batteries at the end of life point most of the materials would come back to new electric car batteries. So it is hard to see how this manufacturing difference could manage any game changing pollution or energy use.
—
So electric cars apparently could dramatically reduce fossil fuel usage and CO2 pollution. I think it is hard to dispute that in honest way based on numbers, facts etc.
Unfortunately cost of electric car batteries in current mareket and industry conditions certainly offset cost of gasoline per overall ifetime of the car as long as gasoline is less than $10 per gallon at least I guess. CO2 pollution today has zero associated cost for polluter.
Under these conditions electric cars could not get any significant market penetration any time soon. Basically world do not have enough economic insentive either for fossil fuel economy or CO2 pollution reduction. That explains lack of electric cars mass scale presence so far.
Sure as many people noticed if battery cost per capacity would drop say 3 - 4 times everything would change. In that case electric cars number in mass scale use would grow explosively until almost compete turn around with gasoline cars. Cost of batteries is the only remaining big issue. So for high end cars because cost is no issue I believe we would see more and more fully electric car models coming in next few years.
About Prius efficiensy :
Efficiensy increase in Prius comes from regenerative braking - basically reuse of energy from brakes or from going downhill. But on the other hand constant use of electricity on large scale during driving introduce extra energy conversion with associated losses.
So we have a balance of two factors with reletive significance determined by driving pattern. If you are driving mostly on freeways and do not use brakes almost completely regenerative braking would not be used but energy losses of electric transmission would still be playing. Under that conditions it is hard to see how Prius could make better mileage.
But for example for taxi driving with many starts/stops because of traffic ligths and just random but short commutes advantages of regenerative braking make it much more efficient.
Basically such dependence on driving pattern makes it harder to compare just mpg numbers introducing wide variety of opinions about Prius efficiensy.
A quick way to swap out battery packs would have service stations selling charged packs for $10 if you left your drained one behind. This would give you great range and make re-charge time meaningless. Service station owners might start installing nanosolar roofs over their lots.
One question i think might be worth thinking about. When we are freewheeling down a hill -presumably the regenerative braking is happening in an electric car due to the fact that the power is not applied and the motors act as generators. This will have an effect on distance travelled as any kinetic energy is tranferred to the battery with associated losses. Has anyone considered if by declutching and rolling down the hill it might be possible to travel further (obviously without recharging battery).
Basically what I mean is:- does the regen energy produced + distance travelled using this regen energy = distance that could be achieved by just freewheeling down a long hill.
Anyone knows that by throttling off when driving down a hill declutching and rolling saves petrol. Could this be employed in an electric car with some clever electronics to disengage drive during certain conditions. i do not know the answers but it might be worth exploring.Perhaps an economy mode switch?
Better Place has just that business model. Battery swap stations more widely seperated, and regular charging plugs placed at parking spots. You then subscribe to their service. Nissan/Renault has already committed to building the cars for them.
Prius efficiency is also due to the Atkinson cycle engine. Where standard Otto cycle engines get about 20% efficiency, Atkinson cycle engines get 30% efficiency, but at the cost of low end torque, which is offset in the Prius by the electric motor.
mark,
The Roadster has regeneration on the ‘gas’ pedal. This means that when you let off the pedal, it goes to a neutral point and if you let it off even more, regen kicks in. At the neutral point, the electric motor freewheels and produces no drag and no thrust, just like declutching an ICE (Internal Combustion Engine). This allows you to determine whether you are freewheeling or using regenerative braking by simply backing off on the ‘gas’ pedal.
As you surmise, regeneration isn’t generally as efficient as just letting kinetic energy build up through speed. There is, of course a speed where the air drag losses exceed the losses of regeneration. Therefore, for optimal efficiency, one would use regeneration if there was a maximum speed that you don’t want to exceed and there is probably a speed at which you should probably start using regen to maintain since you wouldn’t store much additional kinetic energy anyway. I don’t know where that speed is but from JB’s graphs above, its probably around 90 to 100 mph.
I live in Stuttgart, around the corner from the main railway station. I want to travel to Munich, let’s say the main station there to pick up a friend. Once i get on the autobahn, i ll have it do a constant 110 kph (quite slow for german average, i d say). Anyway, bearing in mind i have to get out of the city valley, on to the autobahn and then, after passing the airport i have to gain height again while climbing the swabian alps, do you think i could get to Munich in one go (nice weather, not to windy)? Now, that’s the sort of confidence-inspiring test drive that I’d iike to see here in Germany (or, for that matter, similar trips in the US). Anybody got any thoughts on this??? leo
How about powering the PGE grid to a special lane on the freeways, that would transfer electricity by direct contact or induction as the car travels in the lane. The power would be transfered by a dropdown induction coil or drag unit that would induce energy by the movement of the car from the center cable / or copper grid, to the vehicle for charging as it traveled. With the car moving along in the special freeway lane, a large induction coil moving along close to the power cable or copper center rail, would charge the car. These charging lanes can be installed very cheaply on the special lane, and could extend throughout the state. The vehicles could enter and leave these lanes as needed along the freeways. Induction coil technology would be ideally used for this process, and the technology is available today off the shelf. This would be much better, and cheaper than battery stations everywhere, and would charge right off the grid as the car moves.
Underground high voltage induction cable that charged the vehicle as the car moved could be installed as well.
ron w/
Electricity can be produced by wind energy by the installation of large wind mills as seen on the Altamont pass, operated by PGE, and would be cleaner than using coal plants, and the power delived to the special charging lanes on the freeways. Power use would be billed directly by your local utility company, and would show up on your home bill. Once the large charging capacitor can be developed, and the batteries could be charged quickly, you could use only the wind on a downhill run, to charge the vehicle quickly, and could increase efficency greatly.
rw
I don’t see future in battery swapping model. That would require that batteries for all cars are similar and no new inventions in battery tech happens, which for now is just opposite. Of course you can make “Tesla Model S -battery swapping station” but how would you make this financially viable? There will never be enough “Type S” -cars in close proximity of swapping station to make that profitable. Even that Tesla will be first in business, there are others that follow, and I would be VERY surprised if they had same configuration as Tesla for their batteries. What you would end up with is station with several full battery packs for each model year and each model type and each manufacturer for it to be able to service all that come to get new batteries. Batteries also lose capacity over time, so that is another loss for that model.
What you are using in EV is electricity, not batteries. Swapping batteries is like swapping gasoline tank. What you should do is to figure out how to make battery to battery recharging using high voltages safe. Some batteries can be recharged in just few minutes, so it only depends how high in voltages and amps you can go safely to make battery recharging fast. 15-30 minutes for 100-200kWh battery pack should be considered fast for a car that _only_ uses those stations during very long road trips. That would require 2000V 200A charging system.
Battery to battery recharging model is cheaper (basically same components, only a lot cheaper because you need only one big cheap stationary battery instead of multitude of expensive car batteries), can be used with any battery tech that will ever be invented, and can be used without any standard battery model, only recharging connection would require standardization.
Why can’t you change modes on the fly so that you can go to performance only when desired and back to standard or range?
Why is it recommended to charge it each time it is returned to the garage when you may have only gone 10 miles and know you may only do the same the next day?
Thanks, Bob
leo wrote on January 11th, 2009 at 2:20 pm
I live in Stuttgart, around the corner from the main railway station. I want to travel to Munich
If you look at JB’s table above the Tesla uses around 280WH/mile or so at 65MPH (110Km\h) the Tesla with a 55kWh battery would theoretically go (55000/280) = 196 Miles or 315Kms. A quick calaculation of the distance between Stuttgart and Munich Railway stations comes up with about 200Km.
Looks like even with hills you would be able to do this trip without problems.
Leo of Stuttgart: Tesla Motors is located near the Coast Range in California, and many of their test runs were running through those mountains. Also, Tesla Motors did do a run up to Lake Tahoe in the nearby Sierra Nevada mountains, climbing up through Donner pass. It performed nicely.
Ronald Wose: Good idea, but it needs to be cooridnated with the government as they own the roads, and with several auto makers as no one company would have sufficient market share to make “powered roads” practical by themselves.
Timo: The key to battery swapping is to have one company lease the batteries and run the swap stations - then they’d bw swapping their own batteries for their customers. By using a standard modular design, they could work in lots of different models - a compact car might have just 1 or 2 modules, a midsize 3 or 4, a large SUV or truck might have 6 or more. Nor would it prevent battery improvements, the leasing company could, over time, replace older batteries with new improved versions, a data chip on each battery pack would enable programmable controllers on the cars to work with any new type of battery!
Bob Beyers: Shallow discharge puts less stress on the battery than deeper discharges, so frequent charging will actually improve battery lifespan. The liIon batteries used in the Roadster do not suffer the “memory effect” that plagued old NiCad batteries, unlike NiCads, frequent shallow discharge and recharge will not cause a loss of capacity. Keeping it “topped off” also makes it less likely to run out during an unexpected extra trip!
CM: how would you make battery swapping station profitable? Car batteries cost something like five times as much as stationary cheap battery where battery to battery charging could be made. Also who would allow swapping to older versions of their car batteries? I bet no-one. It severely hurts battery development. You would need to have always that latest design in battery swapping station _with_ all older designs too. Are you planning to keep this same design for potentially 10-15 years? Just plain shape of the swappable battery is a restriction that there should not be.
Getting different EV companies to choose same battery design would prove to be impossibility. Tesla has their own design, Fisker theirs, etc. That would lead to multitude of different designs. What kind of standard would you choose? Where to put it in 18-wheeler and roadster? How to swap that? How about some more exotic work vehicle? Bike? How about having old type S batteries and then going in swapping station to get five times better batteries? How much would you pay for those batteries? What if you don’t want to pay anything extra, and you are satisfied with your current batteries? What if you go to place where there is no _your company_ battery swapping stations? What then?
Battery swapping is like swapping gas tank. It just doesn’t make any sense when you can fast recharge your car using electricity. Just standard three-phase high-amp connector could charge Roadster-size battery pack in something like half a hour, and you can go much higher voltages safely. Those charging stations would be used only by long-range road trips so if you wait for half a hour every eight hours to get your car charged it isn’t that bad. Get a cup of coffee while waiting. Electricity is cheap and people charge their cars at their homes, so getting those stations profitable is a challenge. You can make them profitable only by attaching other services to them. Like restaurants.
Hi
A comment from Sweden:
Formerly on long trips you used horses and when they were tired you changed them. Could you do the same thing with your Tesla either change after say 150 miles to another Tesla or another battery or charge your Tesla fast (3-phase) at a chargingplace for an hour while taking a meal or just relax? You must not be in a hurry all life!
Hi everybody.
I am reading these forums for quite some time but I rarely write something. The thing made me write now are the charts and the data provided by Tesla. Guys this is gold mine for me, I like all the technical stuff and all the calculations that can be made. Here are some of my thoughts.
1. Forget already about Battery Swapping and powered roads. It just CANT be made now. May be in 20-50 years we can have power roads, swapping batteries is totally not viable so stop proposing it almost every day.
2. Although the main problem of the battery cars is the range achievable, I think the bigger problem is the recharging. The more range you put to your e-car the more Kw/h you will need to recharge it and we are getting to BIG numbers here. even 50 kw/h in 10 mins is so hard to do, imagine bigger battery packs (when new batteries are developed). Until we figure this out there are 2 paths for EV’s
1. Keep the recharging at home and hopefully the range is enough for you. (Even 100 kw/h battery pack could be recharged in about 8-12 h at home). That would mean you have to reach destination before battery depleted
2. Make the EV’s consume less energy for mile. Thats the hard part but I think there are things that can be considered here and the benefits are great. As we can all see from the charts the Aerodinamic drag is the greatest force you need to overcome at highway speeds. So any breakthrough or new designes there will bring fruits for the EV’s. I can think of some right now. Some Italian designer removed all screen wipers and used a glass that is repelling water so the water just slides during raining. That only brings down the drag by 5%.
Another things are small but still improving like incorporated door handles, flat underbody (which is easy achievable by EV), I even saw a concept of a car which roof was lowering if there is only one passenger in the car making the car lower and with lower Aerodinamic profile.
Another thing I saw lately was a breakthrough in the Aerodinamic models and simulations. Some MIT scientists figured out the 3d simulation for fluids which can bring to new inventions that reduce Aerodinamic drag.
Thats the correct way all EV’s should orient by my opinion. Efficiency.
Another thing I noticed is that Auxiliary takes about 200Wh energy (even with no lights no AC, no blowers etc). I am guessing this energy is going for the battery pack cooling and on board computers, dashboard etc. If you use batteries that doesn’t need managing that will lower the Auxiliary power needed. You can also take advantage of the latest electronics, and use for example ULV processors and parts for the computers. You can use more effective LED lights in future, you can use PV paint on the car for additional power from the sun.
All these problems make me think that in the future cars will be smaller, more compact and highly efficient. May be we will see a lot of 2 seat cars (one behind another), making the profile of the car half size thus allowing not only 2 vehicles using 1 lane but also reducing the power needed to travel at highway speeds almost in half.
We cant make a global Electric power stations in just few years, that’s not very hard to figure out. However we can see a lot of new EV vehicles released in the next 2-5 years (may be hundreds). So instead of thinking how to make global recharging stations (which is unbeliavably expensive) we better start thinking out of the box and use every idea we have. Because Every Wh energy counts, and the more EV’s are out there the more Electricity we will need and we need to compensate it somehow or add it to our calculations.
May be in near future we will all have 2 vehicles. One small 2 seater (one behind other) city vehicles which will double the density in the cities and one family saloon car for the long trips. The 2 seaters will also greatly help with the parking problem all Europe and I am sure all the world is suffering. And the cars will get more and more (as the people get more and more)
At the end of this long write up I want to wish you all a good health for the new 2009 and let it bring us some great inventions and products that we can use sooner.
Thank you
How is the battery’s effeciency and life affected in the cold? I live in Canada and am definitely excited about the developments happening at Tesla. Would love to see your vehicles make it up here. But was wondering how the performance would be impacted in the cold and in snow driving conditions.
About battery swapping :
In the consumer electronics we could see something like video compression standards for example common for all the products. So nothing prevents to set a standard of voltage, sustained power and peak power for a battery pack regardless with what flavor of Li-ion or NiMh battery chemistry is utilized. Geometry of battery pack may be standardized too including mechanical and electrical sockets. The only difference between battery packs in that case based on chemistry would be total capacity. Sure it could be created a market to make different battery packs by different manufacturers according to standards like these.
Based on the same set of standards different EV could be made. It is possible to modularize the standard so that by using say 1 to 4 modules all the differences in total energy capacity requirement between cars could be covered.
Altogether assuming set of standards is maintained and some significant number of BEV hit the road it appears that we have a model in which we could put any battery pack into any BEV making logistics of battery swapping no so bad as you described.
In terms of business model we could assume that all the battery packs are the property of some big business company. This would be legally similar to how people use Microsoft software under Windows. Microsoft stays the onwer of the software and just lease some installation and use rights to cistomers paying money for that software. So you end up with the model in which you buy the service to replace your battery pack with some energy capacity by another battery pack with bigger energy capacity stored in it. It is feasible to develop some algorithm how much that should cost you. For example it would be a fixed charge for single battery module swap. It would be also cost per kWh of extra energy you got by such swap. I guess it should be also a history of recharges stored in the microcontrollers of the battery pack and readable by some standard protocol. Time of keeping battery pack from previous swap would be also taken into account similarly via microcontroller of the battery pack itself.
As long as you trickle charge at home or any other way you do not pay for battery pack swapping. But otherwise with swapping of leased packs questions of battery life limitations, slow charge and other complications of batteries could be solved in a way that regular BEV drivers should not handle them much. They would pay services for swapping batteries and they are allowed to trickle charge batteries without swapping as many times as they like. Both of these modes of usage seems would solve most of the logistical issues related to batteries including slow recharge.
Having battery swapping stations based on described common standards arranged together with car rental services near airports would expose many people to BEV driving without forcing them to spend a lot of money for “scary new technology”. Same centers could provide services to park BEV for a day or few days. In that case you BEV would be stored without battery pack reducing fee for keeping that pack inside without use etc.
Under all described conditions battery swapping appears to become become fairly routine operation and questions of battery pack design, age etc would be solved by the fact that battery pack is not the car driver property. Sure it exist a question of mechanically robust sockets to fix heavy pack in the car and many other questions. Sure it exist a question of customer acceptance of described use model in general. Sure it exist a question of defining all the right standards I mentioned enabling the model.
But just in general I do not see that answers to all these questions are so certain and obvious that anyone could definitely exclude battery swapping as a potentially reasonable option for BEV. May be this would be the way to go to get rid of oil but still keep conveniences of personal transportation.
Timo, I’m not the one that is going to set up and run the battery swapping system, I’m just expanding on what others have planned, mainly Project Better Place. Battery swaps are technically feasable, but I’m not certain whether it will be used enough to be successful as an ongoing business. I’m also not certain what the terms of the swappable battery lease will be, but I presume it would call for free replacment of any battery pack that fails or falls below a certain performance level. Over time, old batteries would have to be replaced, and eventually it might make more sense to replace old packs with a newer higher performing and possibly cheaper type of battery, especially if the older type is no longer made. Older batteries that no longer performed well enough for automotive use might still have value as “load leveling” batteries for electrical utilities, and finally, at the end, would be recycled.
Obviously, battery swapping would only be used on vehicles designed for it, and swapping would NOT be done on EVs that were not designed for it. Swapping doesn’t make any sense for plug-in hybrids, or slow speed “Neighborhood electrics”, and if “thousand mile” batteries become practical they wouldn’t use it, either.
It is debatable whether “fast charging” is better or cheaper than “swapping”, swapping is likely to be quicker, fast charging stands would take less space and could be more widely distributed. Don’t forget that they are not mutually exclusive, EVs could be designed to work with both swapping and fast charging.
Jube: Tesla Motors winter tested their Roadster in Sweden, and it performed very well on ice, even when very cold. Testing results were posted on this blog, you’d have to go way back in the archives to read it and see the videos.
Has any thought been given to using micro capacitors instead of batteries. They don’t have capacity loss over time, can release their energy more quickly, can be charged more quickly and so on… Also has any thought been given to dividing up the baqttery into sections that can be removed for less weight or added for greater distance or replaced individually to lower replacement cost, or even have a spare set that you can swap out, so the car is always charged for emergencies?
Dan;
in brief, energy density (total capacity) and danger of explosive shorting are the main objections to capacitors.
Dan, capacitors, even ultracapacitors, have a much lower energy density than even lead acid batteries. A capacitor bank big enough to store the same 53 Kwh that the Roadster battery holds would weigh about 6 tons and be the size of a semi truck trailer. Also, because of the low energy density, the cost per Kwh stored would be much higher.
Dividing up the battery pack into removable modules wasn’t considered for the Roadster, due to the cooling requirements of the battery, and also because a smaller battery offers less power - not good for a sports car! There is a possibility a modular battery pack might be used for future models, if certain technical problems are solved and it proves to be practical.
Dear Mr. Straubel:
Thank you thank you for providing real, actionable graphs showing real world performance of the Tesla Roadster.
We enthusiasts hunger for more hard numbers, such as these graphs youve provided, er… provide!
Is there any chance you have a graph correlating battery charger efficiency with charging rate/ and or discharge state?
If not, it might be an area worth pursuing. As a guess, I would imagine total battery charging efficiency would be greatest at very low charge rates (1500 watts or less), due to not needing to run the car’s air conditioning, as well as minimizing i squared r losses everywhere. But it would be intersting to get some info from you on this subject.
Thanks again!
I have some things that have been on my mind since the gm electric car was killed in the 90’s . 1. Why not put a generator of sufficant size on an electric car connected to the drive train so as the wheels turn ( dams have been useing this technology for more then my or your lifetime ) it will be charging the battery by creating eletricity giving the car an almost unlimited distance . Safegards could could easily be put into place to keep the battery from being overcharged . This to me seems elementery . 2. As far as the overheating problem with batteries that I have read about real or not , why not devlop a battery cooling technology . Heat rises draw the heat off the top of the battery is one suggestion . wrapping the battery is anther possible suggestion or both working together . Disregared if you already have a cool battery technology . Better battery tech is always being devloped . 3. Make the recharge connection compatable with existing tech such as sumething as simple as a 440 plug for your home if you do not have that now . I have ideas all yhe time some good some not , and i’m always available at this e-mail address . If you have any questions . I really really want to see this car and your company succeed . By the way have you capitalized your compavy , and is your company on the NYSE , and whay are your call letters , and your exact company name . Thanks John Hill
To john hill :
1. What you proposing here is the same as regenerative braking just implemented without extra gear as you proposed. This is already a part of current Tesla roadster design and is usual part of any EV or hybrid design. Unfortunately most fundamental law of physics is law of energy conservation. Its action completely prevents getting “…almost unlimited distance…” as you put it. You would just get some significant driving distance increase but far from unlimited. The physics law mentioned was established since year 1842 by direct experience of the whole humanity. It is also confirmed by everything humanity observed so far about 13 billion years of Universe existence. Thousands of creative people tried to violate that law by some technical design but nobody get any sligtest success.
2. Heating and cooling of battery pack is also already implemented as part of existing Tesla roadster design.
3. Tesla roadster has a charger compatible with regular residential electricity sockets.
So it seems all you proposals are already implemented in Tesla Motors technology.
I live in Lansing, Michigan. On Wed., Jan. 21, 2009, I had the pleasure of meeting a gentleman (at the dentist office) & in our conversation, he told me that his son is an electrical engineer for your company. This gentleman’s name is Paul, I do not know his last name. We had a great conversation, and I think he was surprised that I was aware of Tesla…….
My significant other and I have both been laid off from our employment and are looking to relocate, hopefully to California. We check the employment site often, and are very interested/pleased with your manufacturing success………..
We remain - Stuck in Michigan for now. Thank you.
John Hill:
Tesla Motors has not yet issued an IPO, no common stocks available. Batteries are water cooled. Please read: www.teslamotors.com/blog2/?p=24
I have become interested in learning more about this fantastic car after seeing it on an episode of Future Car. I believe that the Tesla offers some real insight and potential for future automotive development. However, despite the real advantages offered by the Li-on batteries, what is to come in future battery production; speaking in more readily available materials, that will allow further range, lifespan, use, and development. Certainly, as technology and scale of economy comes into play, the cost will come down; but it seems the biggest factor in future development remains the materials required to produce batteries. What real world alternatives may come into play to aid expansion and increased use of electric vehicles?
Additionally, many have posed thoughts of extending range, or aiding charging via use of petroleum based power plants; what about the addition of a small biodiesel engine to assist in extending battery range by either taking over active devices during high demand conditions, such as blower motors, audio, and lighting? Perhaps even providing a small charging capability to extend range, if only a matter of a couple miles, to reach a recharging station?
Added benefit to this could also be the use of a heat exchanger to aid cockpit/battery heating in cold climate conditions which would aid reducing the demands on vehicle batteries as it could provide the power to it’s own electric fan, boosting it own efficiency. It also helps to keep the Tesla highly independent of petroleum based products, and fuel could be obtained at any supermarket.
These are thoughts and don’t diminish the accomplishment of this vehicle. Since my interest has be piqued, I would love to own one of these; I just have to wait until I can afford one.
I love this information, the graphs are fantastic! I wish there were comparable graphs for a competitive sports car, such as the Porsche, but I doubt few auto companies area as forthcoming as Tesla.
how do the chargers cope with different supplies ?
are they adjustable or made for a certain amps/volt ?
dc-dc/ac converters could charge from pretty much
any electric source even solar panels if you have plenty
of them. (anything over 3-4000 watts should be nice)
wind mills could also charge the batteries with free electricity
would be neat to have a charger adjustable for any voltage 12 volts or more
although the 200+ amps would be a challenge on the parts
Perhaps a 48-240 volts charger ?
I am concerned about the high rpms for the motor, most gas or diesel motors
max out about 5-6000 rpms, would not 13.000 rpms wear out the motor parts faster
what is the epected lifespan for a motor ?
what if the dc-dc power supplies in the battery burns out ? thats the most likely unit to fail,
would that toast the whole battery pack or is it an easy swap to replace this ?
shorts in the dc-dc powers/diodes is the only real issue i see with the battery which would blow out the fuse
for a whole module, hopefully that can be repaired easy ?
can blown fuses in the battery be replaced easy ?
to me a design plus would be easy to change dc-dc powers and fuses for the module packs without having to dissect the whole pack.
what is the cost of the battery since it needs replacing every few years ?
About electric race-cars they do exist, one used about 6000 cells wired in panels
that could be quickly yanked out and replaced. to make the guiness record they had
to finish 2 round-trips in under an hour and had to replace all the cells for each run
What i want from the Tesla:
1. A ‘coaster switch’. that means being able to switch regen off/on.. i like to coast along in my golf tdi on the undulating surfaces. regen for me seems good when the hill im descending becomes necessary to use breaks….not to bothered the energy efficiency of the thing (anyways, it’s all ‘conserved’ isn’t it???), just seems practical in having a choice..
2. Some clear real world testing videos of the Roadster. I am sick to death of watching ex-yuppies drive this thing in their driveways in downtown california shouting ‘awesome’ (ok, maybe i m jealous
). I want people to, wait for it, actually GO TO places with the car, give an insight on real range, good/bad points about the car. A bit of good old down to earth analysis. YouTube is awash with videos, just not the ones i’m on about. I stand to be corrected, however. Links please!
What is the Tesla’s body constructed of?
Who to comment to? Design, engineering, and manufacturing sounds about right. RE: newcast on Federal money for alternative vehicles and not getting approval to break ground in the valley, I have to say this: nice as it would be to keep jobs in California, there’s a whole industry going under in the Motor City, with workers, their families, children in school, etc and no jobs. And a manufacturing infrastructure ready to be retooled rather than re-invented completely here.
How hard would it be to make a deal with GM or Ford to make your cars to your specs? Save some California open space, put some unemployed autoworkers back to work, and hey, maybe put in a few acres of apricots here! Sweet!
rr
I am surprised that the new Roadster Sport doesn’t have improved batteries, at least as an option. The existing batteries are 18650 form factor 2.2AH and although much more expensive, there are better batteries available such as industrial.panasonic.com/www-cgi/jvcr13pz.cgi?E+BA+3+ACA4001+NCR18650+7+WW which are Panasonic’s NRC18650 rated at 2.9AH. Since they are the same form factor, building battery packs with these should be easy. The software for control and charging would have to be changed. For those who can afford it, this would offer a 31% increase in range.
Follow-up on Panasonic NRC18650 batteries. In large quantities I found a web site that offers them at $5 each. I don’t know Tesla’s price on the existing 2.2AH versions but guess at more than $2, so an upgrade would cost 6831 * $3 = $20498. $20k is a lot of money, but since we are talking about a $120k car…
For next generation design, I think GM has it right with Lithium Manganese Polymer batteries from LG Chem. This battery type is also available from www.electrovaya.com/ . LiMn polymer would offer about 50% increase in range, longer life and lower price. Another possibility is www.superlatticepower.com/20080602/ . This one is harder to evaluate since I don’t believe they are actually in production yet, but promise twice the range of LiMn polymer!
The LED-daydriving-lights of the Brabus TeslaRoadster should be standard - especially for the european version with some countries which permits to turn on lights also in bright daylight. There they not only look cool but as a “side effect” actually enhance range!
I’ve got very interrested on your concept from the very beginning, and despite the fact I am living in Mexico and there are no short term plans to distribute Tesla in Mexico, I still keep the dream to own one in the future, perhaps the outcome of the Whitestar project.
One idea that could be implemented on the hard top version would be a flexible solar cell lamination, also on the drive train cover, at least the trial to find out how much more range it might bring on sunny days might be worth to spend the effort to implement it.
Best regards,
All those numbers are great, but what about up here in Minnesota. It gets -40 in the winter and having your car stop in between two towns is not a great way to start your day. How many miles up here?
Phil Johnson: What unit? -40 decrees celcius or Fahrenheit? ….um forget that I asked, that -40 seems to be same in both scales.
-40 is slightly too much for batteries to cope. Roadster battery system does have “AC” for batteries, so they wont get that cold as long as they have charge, but if you leave your car in that kind of temperature for several weeks without charging they would freeze, and then you would not be able to get anywhere. I think that cold batteries wouldn’t even be able to recharge.
OTOH because batteries need _cooling_ when car is driven cool temperature might actually increase range (but that means that passengers would then freeze to death
).
Formerly on long trips you used horses and when they were tired you changed them. Could you do the same thing with your Tesla either change after say 150 miles to another Tesla or another battery or charge your Tesla fast (3-phase) at a chargingplace for an hour while taking a meal or just relax? You must not be in a hurry all life!
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Thanks Timo for your quick response, but you did not answer my question. If I bought one, and I live up here in MN, and the winter is a normal one, and I use the car every other day, and I keep it in the attached garage, and keep an eye on the batt., and when I use it for up to 125 miles at a time, I would think that I would put the heater on max, will the car work well? If I am charging it after the 125 miles I charge it, how long will it take to charge? During the summer I normally put the A/C on max, so will it work then too?
Phil Johnson.
Yes it would (work well). Car has been tested in Sweden for cold climate and how well it behaves in slippery roads.
Heater is (if I recall correctly) 3000W unit, but it wouldn’t need to run with full power very long to heat air in small cabine, seat heaters less than 100W and headlights on would consume another less than 100W so you would have reduced range, less than that promised 200 miles, but it should still be sufficient for 125 miles: battery pack is 53kWh battery, so car uses about 53000*60/200 = approx 16kW / h so with all accessories running at full power you would be using about 17-19 kW /h instead. That gives you about 190-160 mile range. At summer that would be pretty much same situation, only cooling. Using these appliances is not out of performance, just range.
125 miles is about 70% of full battery capacity, so with home recharging unit that would be approx two and half hour to recharge, or 37kW with about 90% efficiency from just about any outlet (depends of voltages and amps you can get out from it).
I can’t wait to own my Tesla - I am planning on the family sedan model
I LOVE what your company is doing and how I believe you will lead the field in our cars on our roads. I believe you will be as important as Ford once was 100 years ago, very, very soon! Keep up your awsome work. I love reading all of Tesla’s blogs.
Thank you from my heart .
a future Telsa car owner,
S Morrill
For me I want to see an Electric car that can do 600km in the depths of winter and the hieghts of summer. If I can get that I will have sufficient range to do all but my longest trips without recharging (I don’t see charging stations in Algonquin Park or the Gov’t dock near my relative’s cottage appearing any time soon). The first electric car that can do that for less than $60,000 Canadian dollars will get my attention and its manufacturer will probably get my money.
Being a former resident of Minnesota, I would have to say that a rock solid endurance test would be to have one of Tesla’s vehicles spend a winter in Minneapolis recharging in some sort of outdoor car port between trips. Yes, I realize that the Roadster spent some time traveling across Sweden and that it was “tested” in a cold climate, but that isn’t the same thing here.
When temperatures get cold…. -40 degrees cold or more …. materials start to get brittle that were much more pliable at warmer temperatures. This isn’t just plastics, although that is an issue. Metals seem much more likely to break, and any lubricants you have significantly start to change their characteristics, along with coolants and refrigerants. Conventional ICE vehicles are usually thrashed in environments like this where I’ve seen steering wheels fall apart, paint flake off, and things like door handles simply break just due to cold. It also thrashes the chemistry of most batteries (especially lead-acid batteries) and their ability to take a charge is significantly reduced at lower temperatures.
The #1 problem I would see with an electric vehicle in a cold-weather climate like Minnesota would be significantly reduced driving range… both from trying to keep the cab warm and from the issues of having a decreased charge in the batteries. Some of this is based on the chemistry of the batteries being used, and some battery types might survive better at colder temperatures than others. Keep in mind that temperatures in Minneapolis also get over 100 Fahrenheit (+40 Celsius) during the summer months, so wide temperatures swings can be expected unless you keep your vehicle pampered in a climate-controlled garage, forcing a further limit on what kind of batteries you may want to use in that environment.
No doubt that Tesla is trying to address cold-weather issues here, but there certainly is an issue here that can be addressed, and it will be interesting to see how the Roadster and other Tesla vehicles will behave when they finally do make it up to the North Star state.
Cablechewer wrote:
## For me I want to see an Electric car that can do 600km in the depths of winter and the hieghts of summer.
It doesn’t take long. Best batteries today already offer that range if used like batteries in Roadster battery pack are used (but they cost more). Soon you might get 1000km range with half the price if battery tech advances like it seems to do.
I too require about 700-800 km range, or charging stations, before I seriously consider getting EV. Just small city car or expensive toy like Roadster is not enough to me.
I don’t like the idea of swappable batteries. At least not before someone can prove to me that it is viable system marketwise in long term (meaning 10 or more years). Especially when you can do pretty much that same cheaper with battery to battery charging where you transfer only electricity which is constant and non-changeable.
Hello JB,
Thank you for a very comprehensive explanation!
I just wanted to make sure you have seen the electricity generating suspension component from a group of students at MIT. Another 10% from the bumps in the road straight into your battery (tested on a hummer assuming more suspension travel from bigger bumps possibly).
web.mit.edu/newsoffice/2009/shock-absorbers-0209.html
Cheers,
/peo
Hello JB,
A power saver for your energy input/output ratio models: 50% less juice for the same amount of Rock’n Roll in your Tesla whilst cruising the CA streets at:
www.businesswire.com/portal/site/home/permalink/?ndmViewId=news_view&newsId=20090210006226&newsLang=en
Cheers,
/peo
Here’s a good idea to generate more power on the road:
blog.wired.com/cars/2009/02/students-at-the.html
www.physorg.com/news153505357.html
energy-harvesting shock absorbers. One example they gave from their testing was generating 1kW average per shock on a 6-shock heavy truck. I wonder how much power this could recover in the Roadster and Model S?
here’s their company: www.levantpower.com/
Hello Tesla guys!
I have a little offtopic question.
What PCD and OFFSET does the forged Tesla Roadster rims have?
Maybe they are fitting for my car.
Best regards.
Christian
Would it make sense to put an alternator running off of the electric motor identical to the current gas engines to help generate electricity while on the move?
I have read articles that say that maybe you, or someone who wants to set up a business off of your car, by setting up a station that will change out the batt. and get you back on the road, on your trip. That way you can drive around on your trip and not have to wait every 200 miles while your batt. gets charged up. You will normally charge up at home, but if on a trip, you will change out the batt.
If the above is all true, do you have people ready to move on this idea?
Also, if you want a test site, we are retired and will volenteer to ues your car and drive all over Minnesota and test it out. I am a retired Sub Sailor who has done 3M and SUBSAFE. Sandie does paperwork even better then I do. We will be able to deal with all of the paperwork to show how your car stands up.
Hi everybody.
I am also very excited about all electric cars. However I have some technical concerns about their future.
Lets start with recharging. By my calculations, having battery packs more than 50-100 kw/h is not going to help a lot (even if better battery technology is developed later), and I think that way because imagine you have a car with 200 kw/h battery pack. You want to charge it from home where you have a regular 220v 35A limit. that means 7kw/h , which means you will need about 30h to recharge it. Even if you only top it up every day, that is not going to help you with the long distances. That’s because when you draw your 200kw/h you will need a power station to refill it up on the way. and its not going to be fast either. Imagine this :
Lets say you need 1sq/mm per KW of cable. So if you want to be able to recharge 200kw/h for 1h you will need 200sq/mm cable. That’s more than 1″ diameter. You cant have such cable recharging your car, not to mention voltages and amperage needed to achieve that and it will not be safe.
The only viable sizes I can imagine are probably no more than 30kw cable which will have about 1/4″ diameter. This will mean that you wont be able to recharge more than 30kw/h or 15kw/30 min. And who wants to spend more than 1h on recharging station? I guess not a lot of people. That leads to the major problem with the electric cars. They have to work to lower the power needed for each mile somehow. Working on increasing battery packs will not help a lot.
Current Tesla is using about 300W/h per mile with 70mph. which means about 180miles with current battery pack. now if they somehow work to lower that to 200W/h per mile with 70mph that will mean increasing range to 270-280miles. And also for every 1h of recharge you get 30kw/h or another 150 miles. So a 70kw battery pack with 1h additional stop during a long travel will top you out at 500 miles. And even if you travel more you will do another 1-2 stops (you will have to anyway, you cant drive 12h without stops or its not very safe)
So the BIG question. How to lower the power consumption.
1. and most important Aerodynamics, Aerodynamics and Aerodynamics
.
at 70mph air drag take more than half of the total power to drive the car. So one way of lowering that is to make the cars smaller. I think future electric cars will be small, minimalistic oriented, every inch will be used as much as possible. big saloon cars are probably not going to work. I imagine 4 seaters and even 2 seaters in a row (one behind another).
Another ways to reduce air drag is use cameras for rear views. Dont know why this is not used widely even now.
Electric cars have lot of potential to have flat floor which helps aerodinamics also.
2. Drivetrain.
at 70mph drivetrain is the next biggest power consumer. It takes about 1/3 of the total power. Now I know Tesla is using gearbox with 1 gear (newest drivetrain). The only reason for that is probably to have a conversion ration for the rpms for the electric motor.
May be more efficient solution will be to have hub motors in each wheel or in 2 of the wheels. If they can make some low rpm high power electric motors that would be ideal. That will remove all driveshafts and gearboxes and etc and I know gearbox takes about 10% of the power alone.
Even more ways to reduce power consumption will be developed of which I am sure but thats the way I think. That will also allow having much smaller battery pack and recharge more frequently, but the total price of the car will be much cheaper.
Imagine a 4 seater small car, which have only 30kw/h battery pack, but weight 800kg. reaches about 200miles on the highway and about 300miles in the city. Takes 1h to recharge at power station, and costs $30 000. I really think that is possible with current technology. We just need to get creative. Think out of the box, and bring new solutions to old problems.
I think electric companies like Tesla should take bigger risks and try to be a little more different in car design
What do you guys think?
Thanks in advance
(Tesla’s big fan)
RawSteel, you have few facts wrong. First of all you don’t need one feet cable for 200kW, you would, if you use low voltage and high amps. Normal household three-phase 100A connection cable is way smaller than that, and gives you about 40kW connection. What requires thick cables is amps, not volts, so if you increase volts you can have that same cable serving five times that wattage. 100A 2000V would be nearly same cable thickness except that you need better insulation. 200A 1000V makes that same thing but cable needs twice the copper. You only need to solve how to make 1000V connection safely. Because normal three-phase is already about 400 Volts that’s not hard thing to do.
200kWh battery pack would be useful, even for longer trips. Just calculate how long you need to drive to get it drained. That 200kWh equals about 800 mile range. With _average_ 60mph (which will almost never realize) that is 13 hour drive. Not many of us are willing to drive that long without stopping for food and sleep over. You could stop for food and charge say 50kW connection for a hour at about every 400 miles (6.30 hour drive) and extend you range to 1000 miles, which gives you second hour stop at 800 miles which extends it further to 1200 miles. You time in the road is extended by two hours. 1200mil / 60 mph is 20 plus those two hours: 22 hours. You have only 24 hours a day, so I would be looking for nights sleep at that time. Eight hour sleep charging with low 25kW (normal three-phase with 65A fuses) and you have full battery pack at the morning.
Of course 200kWh is slightly overkill. 600mile range would be enough for almost all which would equal about 150kWh battery.
You don’t need power station, just battery to battery charging for high wattage charger. Changing batteries is worse. You would need that same amount of power to charge those swap-batteries / car served, and those car batteries cost a lot.
About small and big cars. Efficiency calculations there need to include people carried. It is true that you lose a lot if you use big SUV to transport one person, but for energy usage it would be most efficient to use train or a bus full of people. Small cars will not solve traffic jams even that they would have lower cost to drive / car. Tesla model S with four people on board would be more energy efficient than Roadsters two even with only 75% range.
You wont get much bigger drag with bigger car as long as it is aerodynamically shaped. It is the car frontal area times cars drag coefficient that matters, and car frontal area doesn’t actually get much bigger for aerodynamic five-seater than it does to two-seater. In fact you might easily get lower drag coefficient with larger car, which in turn makes that difference even smaller. What _does_ increase is rolling resistance, but that has more to do with weight than with size. You can’t get much smaller than Roadster for frontal area but you might be able to lower the drag coefficient quite a bit. Roadster does actually have quite a bit drag coefficient, it is far from perfect for that.
Roadster does not have real gearbox. It does have one “gear” with very low energy consumption. Roadster drivetrain is pretty much optimal for a sportcar with single high power engine (hub-motors are worse for high-power car). For 4WD Range Rover -kind of car hub-motors would be _very_ nice, but for normal family car they are not that good. There are few very promising hub motor designs, but not good enough for now. At least that is what I have let people to tell me.
(one tiny thing that bothers me in your writing and I just need to say it: it is “kWh”, not “kW/h”)
Hi Timo
I agree with you on your points. I use kWh because I am lazy to type the /
The 2 seaters I am talking about are cars with half the frontal area, and the 2 people sit one behind another. I think I mentioned it. There are already such designes that work. This will reduce the road area the vehicle takes (thus doubling city density) AND will half the air drag thus reaching much bigger ranges with same battery packs.
The ultimate freakiness will be to design such 2 seater, BUT if you have 2 of them to be able to connect them to make a 4 seater saloon car
Imagine 3 wheel 2 seater. Put 2 of them next to each other. Raize the inner wheels, somehow connect them, give the control to one of the 2 seaters and voila, you get 4 seater saloon. Get back from vacation, split the thing and now mommy and daddy go to work separately
Thats still in the fantasy world but dont tell me its impossible
. I dont believe in this word.
Future will tell
Timo,
correct on the
kwh = energy
kw = power
not really sure what the kw/h designates, maybe just a typo.
I have been wondering about a diesel electric hybrid or hydrogen electric hybrid that would eliminate the range issue? Are either of these options possible? Also, I have read about worries that lithium might run out if electric vehicles become popular. How valid is this fear? Thanks for your time. -Don
Ken;
In a word, no. You’d be using more electricity to generate less. Not smart.
RawSteel have you seen TopGear episode where they drove three-wheeled motorcycle and car mix? That looked like a lot of fun, and that would be just what you mean by two-seater with driver and passenger sitting not side by side but in line. That “car” was able to pivot like a motorcycle but had engine-part (one wheel) steady like a car.
That could be very very good for EV (very low CdA). And also fun like I don’t know what. Small and nimble and easy to park. Perfect city-car and fun in longer trips too (but only for one or max two passengers). Less drag and light construct means much lower Wh / km, which means it could use smaller batteries for same range which makes it cheaper.
Tesla: are you listening? That would be very fun concept for next project after model S. A motorcycle-car -something.
With the work being done by companies such as Fulton Innovation, WiPower, and Powercast, how long before we see the dreams of Tesla realized? Wouldn’t it be great to have induction grids or RF transmitters installed beneath our roadways supplying Tesla Roadsters (and hopefully a wide array of other choices) with all the power (and range) they need?
Great information - bless you!
It seems to me, that a simple test to yield the best real world figures is to install a recording device on as many cars as possible including those already delivered. Given the times and the importance of this issue grant money wouldn’t be hard to come by. I’d bet my bottom dollar that the type of people who have or will buy this type of car are of the the right mind to participate with a minimum of incentive.
Li-ion Batteries permanently lose capacity with time, the amount lost depends on the storage conditions, i.e. temperature and charge percentage.
What loss percentage is estimated for the Tesla’s battery pack over the years?
I like your powertrain set up. With some modifications. I believe you could develop a self powering automobile. Are there any plans to develop a automobile for the common people? Would you be interested in how to develop a self powering car for the common people?
Timo wrote on March 2nd, 2009 at 2:43 pm
RawSteel have you seen TopGear episode where they drove three-wheeled motorcycle and car mix?
Timo someone else is already doing that. See www.flytheroad.com
Mark Melocco, I think that was the “car”, or some model of that car, they drove in that Top Gear episode. Now that I saw it I realized that I remembered wrong, it had one wheel in front and two in back.
That would be perfect platform for lightweight city EV. And I believe extreme fun too, especially if you consider that fitting Roadster engine in that thing is not a big task. Acceleration to 60 maybe 2-3 secs and top speed in somewhere I don’t know -region (you probably could get *much* higher top speed with same RPM range without losing incredible acceleration with that concept.
New battery tech to reduced charge times by 18 times with no loss of capacity.
Full article here news.bbc.co.uk/1/hi/sci/tech/7938001.stm.
I’d really, *really* like to see a “poor weather range” model. This is the Northeast. Assume that the headlights are on (due to rain or snow) constantly, and assume that the heater has to keep the car heated at 68 degrees Fahrenheit. (Assume the car starts out in a heated garage at that temperature, to simplify things.) Exterior temperature in the winter should be treated as 0 degrees Fahrenheit to give a reasonable bad-case scenario. (How’s the car’s insulation? That would make a huge difference to the heating demand.)
Does the winter-weather situation cut the range down massively, or only a little?
The news that came out this past week said that the new tech. on batt. will allow you to re-charge your, Tesla Motors, battery in 5 minutes. . . from you pushing the car to the re-charge station, to cooking out of there at 140mph in under 5 minutes.
Now all we need is to set up places to re-charge. I think that every 200 miles of driving you pull over and re-charge for 5 minutes is faster then we are now with gas engines.
Phil
Mr. Strubel/Musk
Have you considered installing air intakes on the front of the vehicle leading to two or more fans that will connect to and drive a generator to recharge the battery? It is obvious that the wind pushing against the front of the vehicle should be put to use.
Thanks,
LTroutman
Mr. Strubel/Musk:
Have you considered installing air intakes with two or more small fans attached to a generator to recharge the battery while the car is in motion? It seems that the wind pushing against the vehicle could be put to good use.
Larry
All the people I know do not have $30,000 to $150,000 dollars to spend on one of your cars. What today’s working person needs is an electric bicycle. You both have the enginers and the ability to make this. True, it will not make you rich, but it will give the average working person a huge savings in transportation, stop him from poluting, and keep him healthy. I long to see all of us working people using electric bikes someday breathing better air. All it would take is just a little bit of everyone’s time to get this done. I want to be the first one to buy one from Costco for under $300.00.
Please do not think of this a silly. It’s vey serious. Thanks.
I am a high school student writing an electric car blog. I have several questions regarding electric cars and Tesla vehicles in particular.
1. I would think wide tires on the Tesla Roadster would help with lateral acceleration, but have you calculated the efficiency/ range loss v. using narrower tires?
2. What is the total weight and lifespan of the Roadster batteries and can they be recycled?
3. I live in Maine and was wondering about the loss of battery power and range between freezing and -10 or -20 degrees F?
4. If Tesla makes a car all-wheel drive, how much efficiency/range might be lost?
5. Has Tesla tested the safety of these cars to passengers and first responders after they have been damaged in accidents, and how great is the risk of electrocution?
Thank you very much.
Liam M.
When is the reveal of the Tesla sedan? I think I heard it was end of March, but want to be sure to see it. Where will be the best place to learn about it? On a blog or on the site home page?
Thanks
S Morrill
Nathanael: I think headlights, heaters etc. don’t cut your range much (maybe about 5%-10% max), but icy and wet road surface might do worse. That increases rolling resistance quite a bit and those Yokohama low resistance tires would be hazardous to use on icy road. Haven’t calculated, but I bet someone has experimented that. You might lose something like 20% of max range in worst case.
Liam Mullen: for point five: Tesla has fully crash-tested their cars, and their ESS cuts all power off in case of accident. Electrocution danger is probably less than burning in gasoline fire. Tesla Roadster has also been in real-life accidents (just look at google) and it turns out to protect their passengers very well.
Larry Troutman: any wind turbines in front generate more wind resistance than they generate electricity, so those would be worse than useless. There is no free energy.
Liam Mullen:
1. Tesla has special tires designed to have lower rolling resistance but still be wide enough to be “sporty”, after all it is a sports car.
2. The battery pack weighs almost 1000 lbs, and is designed to maintain performance for at least 160,000 miles. Recycling the batteries has already been arranged. www.teslamotors.com/blog4/?p=66
3. There would be some loss in range due to cold weather, mostly due to the requirement to heat the car and not because of efficiency loss in the battery itself. The battery has a built in heating/cooling system. www.teslamotors.com/blog4/?p=55
4. A 4-wheel drive version should actually be more efficient. Most of the braking energy is consumed by the front wheels, so the energy recovered can be higher in a front wheel drive electric vehicle. Tesla is rear only drive primarily to keep the cost down as a second motor and controller for the front would raise the price and also increase the weight slightly.
5. Tesla spent most of the first few years on battery safety, It is the only large battery pack certified for air travel in the world. www.teslamotors.com/blog4/?p=61
I have been intersted in your car design since i heard about on npr. Reading about this car and the state of the art tec. you are using i thinkit is great. I do have an idea if usable have you though about scaveging what from the moter and using it to help heat the car. Just a thought Terry Pokorny
Thank you very much Roy for all of that information.
On my blog am also comparing and contrasting electric cars with fuel cell cars. I realized that I still have a few quick questions and I need an expert’s opinion:
1. Which do you think are more promising, electric cars or fuel cell cars?
2. Will fuel cell cars be cost competitive with electric cars?
3. Do you think it will be more difficult to make hydrogen stations or battery swapping/charging stations?
4. Will this be a deciding factor in which car will be more broadly used?
5. Are you aware of any other possible fuels such as bio-diesel which be competitive with electric or fuel cell cars?
6. How long do you estimate that it will take the United States to transition into using only alternative energy cars?
Please leave your first and last name and your job description.
Thanks again in advance.
First question why don’t you use Lithium-titanate batteries? Second question, why don’t you use in-wheel motors? It would dramatically reduce some 30%-40% power loss due to the need of mechanical transmission. By placing in-wheel motors you get rid of both extra weight and gear mechanical transmission power loss, thus increasing efficiency. Theoretically this would also extend range / charge. Also, the Lithium-titanate battery would drastically speed up the re-charge process.
I don’t know how long Lithium-titanate battery have been around, i suspect they’ve been around for some time, seeing as the company that makes them is 50 years old. It may be that you were trying to save costs for the consumer. I think I heard a figure of the battery costing $100,000. If so I can readily see how the could be a sticking point.
I know that in-wheel motors have been around for at least a century though. I could only assume that investors were wanting a very quick turn around from investment time to production time.
If these questions have already been discuss don’t hesitate to contact me and inform me of my wicked ways.
Kevin Cardinale
Las Vegas DUI Lawyers Yes I have a vested interest in your success. Come hell or high water, my next car will be all electric.
Wow! Skip the graph… Whatta road! Run as fast as you can…
Thanks so much for the link to the data. I’ve been scouring the web for data like this for my master’s research project, and this hit the spot. I love the openness with which Tesla conducts business - it is so hard to even get a drag coefficient out of the likes of Honda and Ford.
Way to go, and best of luck with the “S”-
AP
Liam Mullen:
1) BEV definitely. Fuel cell cars need hydrogen distribution network and generatin hydrogen needs a lot of energy. There just is no point using fuel cell car when battery tech is showing near future advances of approx 1kWh/kg energy densities. Everybody already has electricity coming in their houses and generating electricity can be done in about billion different ways including in house solar cells.
2) Don’t understand question. Fuel cell cars are basically EV:s with pressurized hydrogen storage unit and fuel cell converting that hydrogen to electricity instead of battery.
3) Battery charging is what can be done everywhere _NOW_. Fast charging batteries can be done nearly everywhere with negligible change in current grid infrastructure. Any roadside restaurant already has capability to charge BEV, all you need is to build connector for car. Hydrogen transport/storage infrastructure doesn’t exist.
For this point 3 I need to point out that current thinking of “drive to station to fill up/charge cars” is nearly non-existent in BEV world. Everybody is charging their cars in their homes, and charging stations are needed _only_ for long road trips. That charging can be made longer because that is not something that you need to _drive_ your car every week or so to fill up. You just take short (30-60min) break in driving and continue after eating or drinking cup of coffee.
4) Yes and no, because charging stations are not even needed ever for 90+% of people driving BEV. For fuel cell cars you need it.
5) bio-diesel ruin environment and lower biodiversity in areas where it is produced. Also EV is just simply superior in efficiency and performance.
6) maybe about 10-15 years total. BEV is now reaching breakpoint in battery tech and after that ICE is just obsolete. Tesla is just first in market, soon there will many many more.
Kevin Cardinale: In-wheel motors may reduce transmission losses about 30% of less than 5% what it is now. So you end up with 3% energy loss instead of 5%. No big deal. In-wheel motors are weaker and less efficient than Tesla one motor solution so you would actually lose some efficiency. Weight is also not a issue here, transmission + shafts don’t weight much.
What could be useful is in-wheel motors in front wheels and single motor in back. In that way you could get better regenerative braking energy recovery and add some power to car.
Battery charging speed is really not limited by batteries, you can’t fast charge 50+kWh battery pack very fast unless you have nuclear power plant at home. 50kWh needs with (un)usual 100A fuse 500V in order to charge it in a hour. Pretty much any modern battery can be charged in a hour. What should be looked at are energy density, safety and price of the batteries.
Kevin Cardinate: Read www.teslamotors.com/blog2/?p=24 and www.teslamotors.com/blog2/?p=39
Liam Mullen:
My name is Roy Harvie, and I do not work for Tesla. I have been fascinated with Tesla for several years and have read literally every word on this web site. I have gone through a career change from electronic technologist to computer programmer.
1. Years ago the car makers spent a lot of time and money trying to create a viable battery system for cars. They failed. Eventually they turned their interest to fuel cells. The Oil companies encouraged this trend because they know that they will run out of oil and fuel cells have the advantage that they could keep their customers coming to the pumps to buy hydrogen. Tens of billions of dollars have been spent on fuel cell research, many more times than batteries. The last thing the oil companies want is to see customers charging their cars at home. Mean while battery research continued and great advances have been made. It’s all about size weight and energy density, how far can you travel on a tank of hydrogen vs a battery pack? Which costs more? Battery break through s are happening almost daily now and is leaving the fuel cell camp in the dust. There is no question that batteries are much more efficient, about 95% vs 50% for fuel cells. Charge time for batteries can be about the same as fueling time for hydrogen. Battery swapping is a bad idea, why swap when you can charge just as quickly? In a few more years even die-hard fuel cell advocates will give up completely.
2. None.
3. Who cares? Both are losers.
4. When a low cost battery can take a car 800 miles on a charge, the whole world will go electric. When you can charge over night and drive all day there will be no more need for gas or diesel vehicles.
5. No.
6. 10 years. I know most people talk about 20 to 40, but I think it will happen much faster. As soon as point 4 is reached, no one will buy anything else.
Roy, what range do you think is the breakpoint for EV making ICE obsolete? You mention 800 miles in your answer to Kevin.
I think it is 600 miles. That means 10 hour drive with 60mph average speed. If you need to drive longer you need charging station, but I think for that half hour or even one hour charging for additional 200+ miles is fast enough (you take one hour brake in driving while car is charging). That would give you that 800 mile range with ~14 hour driving (14.20 to be exact).
For 1kWh/kg energy density that 600 miles means something like 180-200kWh battery for ordinary sedan assuming ~300Wh/mile with 60mph average speed.
That would weight then about that 180-200kg and take space about same as 100liter gas tank or less. That is small enough that combined weight of battery + engine + transmission + controlling units + cooling takes less space and weights less than ICE + transmission + gas tank.
I think that long-haul truckers need charging stations that work as restaurants as well. Those can then be used with normal sedans too. When truckers change to BEV ICE is gone for good.
have any customers told you their observed range in real life driving.
I’ve seen the car perform and it’s really a step in the right direction for cars
I was wondering if anyone thought of using a air ram to charge the car as it’s being driven
they are a safety feature in the airbus planes maybe it would be a way to increase the range of the car
I just read Nature article about 60mAh/g 400C batteries. Text talks about 170kW/kg power density. That’s _ONE KILO_ of battery for 225 HP for about 9 secs. 50 kilos for 11250 HP which is less weight than nitrodragster uses fuel in one 1/4 mile run.
Drag racing anybody? How big engine you need to cope with that kind of power? What about wiring? Ordinary cables would melt in milliseconds with that amount of current.
I would very much like to see EV beating nitrodragster.
www.nature.com/nature/journal/v458/n7235/full/nature07853.html
A few words about range and fast charging.
1. Energy density and range - article about future batteries chemistry : www.batteriesdigest.com/lithium_air.htm. The theoretical energy density is 3.6 KWh / kg (while the practical estimations are 25% of this ). The 0.9 KWh/ kg increases a Roadster range by 5 times to 1220 miles.
2. Fast charging - fast charging of Roadster battery ( e.g. in 10 minutes ) requires a 300 KW. In case of several vehicles charging simultaneously the power required can be a problem for potential charging locations. But there are several technologies that can provide enough power by using some kind of accumulation, e.g. using flyweels as it used in this www.pentadyne.com/site/our-products/technology.html
I am a Japanese very interested in pure EV.
Nowadays rechargeable battery technology is in great progress for to utilize in automobile industry.
I think TESLA business model is perfectly correct where additional engine generator to feed electricity to the ESS is not adopted.
In near future bettery energy density will be far raised resulting unnecessity of additional complex structure of engine generator.
Recent news from Japanese Research Organization( AIST) is very interesting to me.
The news is telling that improved LITHIUM AIR CELL have been invented at AIST
of which energy density realized up to 50,000 mAh/g.
I think LITHIUM AIR CELL is the best way to be adopted in future TESLA CAR.
www.aist.go.jp/aist_j/press_release/pr2009/pr20090224/pr20090224.html
I was curious as to whether this technology could be used to power a vessel on the water. Say the vessel is large enough to carry two sets of batteries, (50 ft in length, with hydrofoil capacity,) and has a small generator on board to recharge the batteries not in use at the time. (For instance using the port batteries while the starboard batteries are being charged by the small generator, and vice versa.) Understandably there are different forces at work on water than on land, but is this conceivable to say building a 100 ft aluminum hulled vessel with the hydrofoil capability to moving swiftly over the water at speeds in excess of 86 knots with twin propulsion drives such as this, and how much larger would these motors have to be? With each motor attached to a dual propeller drive system such as say Volvo’s IPS system has.
John S. Keller, battery and electric engine powered boats have been utilized for over 50 years now. For example all WW2 submarines used batteries when submerged and some of them were faster submerged than surfaced. Nuclear powered big ships are all electric. So batteries definitely can be used for boats. Electric motor is much smaller than similar power ICE, so engine size is not the limiting factor. Batteries are the thing that take space in electric boats, but like they do for cars they get smaller for boats too.
Fukushima, could you post link to English page, please. My Japanese is a bit rusty so I didn’t “quite” understand what is being said in that page.
I just got my latest Nature volume and it had quite interesting article about magnetism that makes possible to build “spin batteries” that convert magnetic energy directly to electric energy.
However that article is somewhat difficult to understand. It is like reading a script of new Star Trek movie where “particle of a day saves the day”. If someone here understands what is being said in there in plain English (meaning potential Wh/kg or W/kg or something like that) I would very much like to have translation for dummies.
Full article is here: www.nature.com/nature/journal/v458/n7237/full/nature07879.html
Fukushima, can you confirm what I’m reading from that figure in page you linked:
2,5V 50000mAh/g capacity? That is 125000Wh/kg or 125kWh/kg. For energy density that is unbelievable. For power density that is something I can understand, but for energy density that is like having one kilo laptop battery that could run 2000 hours straight. Or run a Tesla Roadster for 575 miles. There must be some error in that article, last time I read about lithium-air batteries theoretical max for them was 11kWh/kg.
However, if that is true, then who cares about “silicon nanowire” batteries with 10 times the capacity of current batteries. That is 500 times capacity of current batteries. Put 100kg of those in a car and drive 50000 miles without recharging.
# Timo wrote:
## Nuclear powered big ships are all electric.
Actually I think many just use steam from the reactor to run steam turbines.
en.wikipedia.org/wiki/United_States_Naval_reactor
quote:
“U.S. Naval reactors are pressurized water reactors, which differ from commercial reactors producing electricity…”
“The Russian, US and British navies rely on steam turbine propulsion, the French and Chinese use the turbine to generate electricity for propulsion.”
Timo, check this one:
www.globalsecurity.org/military/library/report/gao/nsiad98001/fig-i-2.gif
Rather off topic from Tesla.
So, more on topic… Model S reveal is expected to be live streamed March 26th at 12:30PM here:
www.leftlanenews.com/tesla-model-s-live.html
Fukushima: Unfortunately I don’t understand Japanese, and could not find the article listed in the English section. If it is very new, then maybe it just isn’t translated yet. Lithium-Air batteries have long been known for their extremely high energy density, but only as primary batteries. That is not rechargeable. Is this new design rechargeable?
Timo: I agree with your analysis exactly. I think a battery for a car would have to be rated at 800 miles, before a driver would go 600 without anxiety The Tesla is rated at 244 miles but practical range is about 190 so for this factor, 800 -> 622 miles.
Carl Scharnhorst: Read Something for Nothing in www.teslamotors.com/blog2/?p=24 How can air ram charge be a safety feature in an Airbus?
Timo: Possibly this link will help in understanding magnetic storage www.physorg.com/news156011642.html . Can’t say that I follow it that well myself, but looks like nano-scale inductors can efficiently store and return large amounts of electricity. If you think in terms of large scale, an inductor, capacitor pair will resonate at a certain frequency and stores power while resonating. In practice the resistance in the circuit robs energy and the resonance will die to zero, but if it was made of super-conductors, it could store power for a long time.
Bravo to everyone who worked on Model S - it looks spectacular.
Yes, the M-S is beautiful. With exceptional features.
My name is Stoian Kalniev. I have traveled all over the world and have family members working for the UN on sustainability and environmental projects. I have sent an e-mail to Tesla some months ago, but never received a reply.
Because of my family, we are very knowledgeable about “green tech”, and currently I live in Thailand. The Asian market is the one that is expanding very rapidly and welcomes current and new car makers into the market, with promise of profits (i.e. India, China, Japan being a car lover country, etc.). However, these countries really need to see the benefits of both Tesla models. I have been going around import companies and asking them if they know about electric cars and they look very puzzled.
You must enter this market if you want to finish your financial debts, reduce costs to make the vehicles cheaper
and make your product awareness and eventually conquer the vehicle industry. I also know that you get your batteries (maybe most of them) from the Thai market. If you open a factory here, you will drastically reduce your costs, allowing for a broader consumer range.
There are more reasons for me to explain why you should enter this market. Please reply to me to know if this plan is sound, so that I may build my confidence of one day seeing a Tesla (the sweetest, hottest, most useful car on earth) with my own 2 eyes on these roads.
Thank you and hope to hear from you soon
A simple question, Can the vehicle be recharged whilst in motion?
If so, can’t a portable generator be mounted to a tow-bar and charge the car whilst in motion?
This really come in handy especially if you going to drive a long didtance.
Thanks.
What are the NEC requirements for the vehicle charging circuit? Have you guys spec’d a NEMA receptacle configuration yet? I’m an electrical apprentice in the Denver area and I expect there will be the potential for jobs in my future to provide the 240V service in the owners garages.
I really wish I could afford one of your cars - maybe I’ll buy the ‘blue star’ when I get my journeyman license ;^)
Ron
Fukushima’s article seems to translate well enough with the Bable Fish to be able to at least get the basic gist of what is covered… it is a proposal for a new electrolyte and packaging format for a Lithium-ion battery. There are multiple markets for high energy density storage devices, so it seems reasonable to keep pushing the technology. Apparently this “discovery” is being announced next week at a Japanese energy conference, and this is sponsored in part by the Japanese government (the Japanese corporate culture is a bit weird compared to America/Europe on this point, and I think the sponsorship issue is lost in translation). It is the sort of incremental progress that I would expect for a battery manufacturer, but the amount of improvement obtained here seems a little too good to be true. Time will tell, although it looks like there are some people with some deep pockets to get this technology built if the theory holds true when scaled on a commercial basis.
The Tesla strategy is to not be dumping the money into the battery technology. There are plenty of people who are working on the next generation of battery storage devices that it would be a waste of time and money for Tesla to gamble what few dollars it has into some crazy speculative energy storage technology. The standard Lithium-ion batteries exist today, and one of the genius moves by Tesla was to take off-the-shelf Li-ion batteries and put them into a production vehicle. That is the hard part…. where alternative storage devices would certainly be capable of being swapped in for what Tesla is already using.
You want to prove your device works so well? Buy a production Tesla Roadster and put your cool little device or Mr. Fusion machine and demonstrate how you can travel from NYC to LA on a single charge. That would impress a whole lot of people. Heck, Los Angeles to Las Vegas and back would be impressive enough.
I have to admit, the Model S is a stunning 4 door vehicle. I was up in Redwood City last weekend and sent an email months ago requesting a tour of your plant for our Corvette Club group but no one ever responded. Instead, I was put on your email list. Would I get the same “no response” if I drove up to Redwood City again to see the Model S in person?
Congratulations to this blog and the Tesla-Motors-Company as well!
For me as an average German citizen the current dicussions are a little astonishing.
While you are discussing range, duration, power, effectiveness of the Tesla car on a high technical level,I would be interested in
just everyday consumer experiences, although the roadster is not comparable to an avarage family car.
For mass circulation of EV for the consumer is determing if he or she can drive to work an back, shopping or lunch in between maybe,
in city and on highway and country road as well without charging. And if one has a long distance trip, where to charge in between?
E.g. the way to work in Germany averages 1 jour drive, appr. 30 miles.
I tell this long story, because TODAY a german motor magazine (”autobild”: www.autobild.de/artikel/tesla-model-s_875572.html)
published an article about new Tesla Model S, and I thougt immideately “thats my next car!” I came to know Tesla Motors maybe 2007,
and I loved the design of the roadster, but I find roadster impractical an too expensive. But the Model S seems to become a very useful car,
it is affordabe (for european standards) and nevertheless the design is stunning!
I am displeased about the automobile industry, because they failed to develop innovative engines. Although the german brands
built very effective motors and (expensive) features like using brake energy for electricity, LED for headlights, start-stop engine and so on,
but alternative drive can hardly be found. Only LPG and Hybrid Drive (mostly in Japanese cars). So you find only few blogs
in Germany on topic. and there I find the belief that EVs still are small and ugly, or ineffective. People seem not to know (or don’t
belive?!) that an EV can drive faster than 80 mph, or longer than 2 hours! Therefore I sometimes get the impression the diffsion progress
is beeing constrained. Even the Tesla is unfamiliar to most people, or they smile about. The electric drive ist not taken serious in Europe, yet.
I would like to see Tesla go on further developing thir engine and maybe more models. And please launch your cars to Europe! (PS: why Munich?)
Hello i hve i a problem your cars cost too musch im a student and i like to drive a electric car but i have not so many money but i think ther must a possibiltiv to bulid low cost cars so every one can drive a car withe elecktric motor so im only a famly guy withe a littl son but a have a dream and so i wisch too see the world with out paying for pertol have a nice day.
I love the extensive design that has gone into this. Recently I read something about the old steam engine cars. The article said that if they were designed today that with today’s technology they could be very efficient. I thought to myself that TeslaMotors can extend the distance of their vehicle with a electric/steam hybrid. If done right, it might be able to make the car run indefinitely by having the steam engine power the car and charge the batteries. It seems that everyone is stuck in the Gas/Electric hybrids; maybe it’s time to break the paradyme. Any thoughts on this?
Wow, great stuff to be able to study. I love these cars, they are the answer to SO many of the world’s problems, especially the US dependance on Middle Eastern oil. How glad I’ll be to finally wean myself from gas stations once I can afford my first Tesla. I hope and pray that’ll be soon!
Do you have or plan to have any licensure programs for auto repair of Tesla vehicles? As a future customer how would I ensure it’s upkeep and maintenance? Are there certified repair shops in NYC?
Anke, Tesla has started a cooperation with SMART car, 1000 cars will be sold.
WOW !! I live in Miami and just got back from L.A. where I had the opportunity to test drive the Roadster. OMG it was the best experience ever. While the roadster is not practical for a family, I am excited about the new S model that is coming out. Lets see, I could buy a Chevy Volt or a Tesla Model S…let me think about that for about a 1/2 sec. BZZZZZZZZZZZZZZZZZZZ I choose the Tesla Model S there is no comparison. Good by GM FORD LONG LIVE TESLA MOTORS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Is a/c a standard option? How will the air conditioning work, being all electric?
thanks, Bruce
Ken: Tesla Motors decided not to make a “plug-in” hybrid, as their battery only design achieves a fairly good range, and with “less than one hour” charging could be practical even for long trips. If Tesla had decided to make a plug-in hybrid, there are many possible choices for the “range extender”, including standard piston engines, wankel engines, gas turbines, stirling engines, and steam. Of those options, steam is the least satisfactory, for automotive use steam isn’t very efficient, consuming more fuel, and car radiators are too small to condense all the steam which means frequent stops for water fill-ups.
Bruce: I imagine the air conditioning works very well. Like most hybrids on the road, the A/C is electrically powered and the compressor is completely sealed, making for a very reliable low maintenance system.
What impact will a camping trailer, or indeed any trailer, hooked on the car have on the cars range?
I cant imagine anyone using a Roadster doing this, but the Model S?? The Model S seems to be heavy enough to safely tow a trailer of at least 1500kg. Is indeed a towbar an option at all?
I do not understand how you can claim to get 244 miles per charge with the Roadster when GM’s volt and others are claiming 40 miles per charge with the same Lithium Ion battery technology. Where is the disconnect.
I would be interested in working with Tesla to develop a model designed for operation by those of us with physical disabilities. Is there one in the works?
# Joe Simone: ” I do not understand how you can claim to get 244 miles per charge with the Roadster when GM’s volt and others are claiming 40 miles per charge with the same Lithium Ion battery technology. Where is the disconnect. ”
Battery size in kWh. Plain and simple. GM and some others also use weaker energy density batteries than Tesla.
GM Volt doesn’t exist yet, so it might be that it doesn’t get any miles per charge before GM goes bankrupt.
#
Timo wrote on April 1st, 2009 at 1:04 pm
# Joe Simone: ” I do not understand how you can claim to get 244 miles per charge with the Roadster when GM’s volt and others are claiming 40 miles per charge with the same Lithium Ion battery technology. Where is the disconnect. ”
Battery size in kWh. Plain and simple. GM and some others also use weaker energy density batteries than Tesla.
GM Volt doesn’t exist yet, so it might be that it doesn’t get any miles per charge before GM goes bankrupt.
You are correct in your comment about GM battery not yet existing. I suspect the battery they are waiting for is the same technology Telsa is planning for the S model. There is no magic here that get over 5 times the range with a similar Lithium Ion technology. Smart engineering may get another 10% to 20% or so. There are no dumb engineers in either camp. Maybe it is 1000lbs of battery, roughly half the weight of the car that does it. I do not know what battery size Toyota, GM and others are planning. Does anyone know?
Joe Simone: The Tesla battery is more than 3 times bigger, and heavier than the Volt battery.
GM’s Volt is planning to us a 375lb Battery pack yielding 16kwh for a 40 mile range verses the Roadster’s 1000lb 55kwh battery pack for a 244mile range.
Joe Simone, seems that you found out yourself how big GM Volt battery is.
16kWh/375lbs = 16kWh/170kg = 94Wh/kg vs 53kWh/450kg = 117Wh/kg
16/53 = 0,301
40/244 = 0,163
Weaker energy density, and much weaker range probably because car itself has aerodynamically poor design and it has to drag along excess weight from internal combustion engine. With same design as Roadster it should have nearly 80 mile range.
I’d say that car is obsolete before it is even born.
Joe Simone: I didn’t realize that the Volt battery pack weighed that much. An important factor is that the Roadster is a very small car and as the frontal area is significantly smaller, then it requires less energy to drive down the highway.
It is interesting to see what can be done if you optimize for an all electric vehicle as is the case of the Roadster. The VOLT and other plug in hybrids are talking of a range of about 40 miles after which the internal combustion engine kicks in, and they are burdened with the extra weigh of that engine a generator and a gas tank.
You have to consider the logistics of how you replenish your charge after you exceed your vehicles range, since there are now no electrical recharging stations available. With a plugin hybrid you can always stop at a gas station. I believe the thinking is that the plug in hybrid has an unlimited range since there are gas station everywhere. If the average commute is 40 miles than all energy comes from the power grid. If the average commute is 80 miles half the energy comes from the power grid. So you have an unlimited range and an average saving of 50% to almost 100% on the use of gasoline. In the future it would be desirable to install recharging or battery swap stations. One has to consider the recharge time. It also may not be practicable to swap out a 1000 pound battery, and maybe you might prefer to keep your own battery (it may be newer).
One also has to consider that when we start getting a large amount of our vehicle power from the power grid we would have to substantially increase it capacity. Right now our electrical power is supplied from 50% coal burning, 20% natural gas and 20% Nuclear and the rest from hydro, oil, wind solar. Coal is very very dirty and clean burning coal is a long ways off. Nuclear energy would provide the cleanest form of almost unlimited electrical energy allowing us to charge our vehicles.
Why not use a magnetic transmission?
We have developed a magnetic gearing and coupling system that works great. It has been in use in Australia for some years now.
The gears never touch each other. They are 22% more efficient in transmitting power (compared to mechanical gears) and they never wear out. They run quietly and they can be dimensioned to slip at a given torque value. In some applications, such as boat transmissions, they can transmit power through the hull. The gears can be used to re-generate power when braking.
If I could get some specs from Tesla I could look into the feasibility of manufacturing a prototype magnetic gear box. We are in fact targeting electric car/scooter transmissions now, and will exhibit at the Hannover show in Germany this April.
I have read much of this blog but have not sees any discussion concerning the development of superconductive materials and how that might affect the viability equation. One can try to increase the energy available or try to reduce the energy consumed. Is Tesla motors looking into this subject?
Bravo for all the hard work you’ve done thus far. All electric is the way to go. I am also glad to hear that EVs are viable in cold climates like Montreal.
Joe Simone: Tesla is currently using a 54 Kwh LiIon battery pack with a cobalt oxide cathode with higher energy density and a lower cost per Kwh stored. The GM Volt will be using a smaller 16 Kwh LiIon battery pack with a manganese spinel cathode, the energy density is a little lower and the cost per Kwh stored is higher, but since the battery is a lot smaller the total cost is lower, but because it is smaller it must withstand 6 times more charging cycles to go the same distance as the Tesla Roadster, and it does.
The result is that Tesla and GM are using radically different approaches for plug-in cars, and that requires different batteries.
Hallo, meine Frage in Deutsch: Wie sieht die Energie-Effizienz (Reichweite) aus, wenn im Winter Sitzheizung, Klimaanlage, Kabinenheizung und Scheinwerfer benutzt werden?
Danke!
U. Schreiber
Save the Auto industry?? DOES THE GOVERNMENT REALLY WANT TO END DEPENDENCE ON FOREIGN OIL?? I don’t think so and I will tell you why, as well as, explain how simple it would be to accomplish these things and most of Obama’s aspirations in one feld swoop. First, why does the government NOT want to end dependence on foreign oil?
Consumption would have to be reduced by 50%, which would cost the federal government and state governments hundreds of billions of dollars (a $10 a pack tax on cigarettes would not fly). Second, it would devastate the oil industry (not that anyone I know would care) and might have adverse effect on stock markets. Lastly, a lot of representatives have a personal interest in oil companies via campaign contributions or more direct interests.
If the government did want to follow through on this and end our dependence on foreign oil, reinstate the U. S. auto industry as the global leader, reduce green house gases and smog to a level of insignificance, and alternative energy a household necessity equaling the inception of personal computers; the technology is here, and the time is right. I can see that if Obama accomplishes this, re-election would be a surety. Let me first say I am an engineer and the answer seems quite obvious. GM’s answer to a “Clean” car is an undersized, underpowered, underwhelming EV called the “Volt”, unable to operate effectively at highway speeds with a range of 40 miles. That doesn’t really compare to conventional cars, does it? Basically there might be a few fanatical tree huggers that would suffer with this piece of work so they can boast how small their footprint is. What if there was a car that would exceed the performance of conventional gas-driven vehicles, has a range of over 300 miles, can be recharged in 45 minutes, or charged overnight FREE? Think of all the taxis in the U.S. having no emissions. A power plant capable of pulling large tractor-trailers. Personal cars which cost nothing to drive. No fuel cost, no maintenance costs associated with gas engines (oil changes, filters, tune-ups, etc.). No necessity for major infrastructure changes like with Hydrogen and other alternative energy solutions.
ALL THESE THINGS ALREADY EXSIST. There is a company called Tesla Motors, which has been making a car that does just that. Oh yeah, it is a high end sports car, a niche car, too expensive at $100,000 to be considered a viable replacement for use as a taxi. Now get your head out of your “box”. Let see, why does it cost so much? How many do they produce in a year? Very little. What value is built into this car (quality of components, implementation of technology, comfort amenities, etc.)? The highest available. Actually, all things considered, I imagine the efficiency of manufacturing for this car surpasses the Big Three. But consider what a car could be built for if was mass produced as a basic means of transportation. This company has designed a midsized four door to be produced for $50,000 and is asking the government to loan them $450 mil to help start up of its production. Again it is a car with all the comforts of a high-end luxury car. What if we didn’t give them $450 mil ? What if we gave them $4.5 billion to step in and fit their power plant into GM vehicles? Without the need to change basic design of the vehicles, the effect would be unbelievable. Almost overnight (before the next primary) the U. S. Auto Industry would become the global leader in auto mfg., dependence on foreign oil would be a thing of the past, and our environmental “footprint” would be drastically reduced. Hmmm, seems like I recall rhetoric professing to do just that. There is also another company building a plant in Kentucky called ZAP that will build a comparable vehicle to the Chevy Equinox or Nissan Rogue for about the same money.
Oh yeah, I said something about FREE fuel. Solar charging units can be designed and sold along with these cars so that average Joes can drive to and from work each day and pay nothing to recharge their cars. This will also make it more attractive for homeowners to opt for larger solar systems that would reduce or eliminate the use of commercial electricity in their home. I would say on average the annual cost for fuel and maintenance on autos exceeds $3000. I don’t know how low the price can get on scaled down models, but I am certain it would be less than $25,000 and more likely less than $20,000. Over the life of the car it would almost pay for itself.
Fact:
The technology exists now.
The time to do this could not be better and may be critical not just economically but also to national security.
Most taxis could run all day without a charge, but if not industrial chargers can recharge in 45 minutes.
U.S. auto makers would go from bloated aristocratic idiots, to global industry leaders.
Finally; our government would be focusing their attention (AND OUR MONEY) on a solution to a critical problem our nation faces, which would actually benefit the people who put them in office. How ironic is that! And it would probably be more of a “Stimulation” than $13 a week.
Also, if the powers that be could include leaders of magnetic motor technology in their development, we might see ranges of more than 3000 miles without charging. But they probably need to incorporate computer technology to manipulate magnetic angles and gaps to make them feasible.
Ken;
What boils the steam? Burning logs? Hunks of coal?
Matthew-J;
TeslaMotors will own and operate all outlets and service depots.
Joe & Timo;
The Volt is not pure electric. The other motor and its fuel make a mass and volume trade-off. It has a 1 L. 3-cylinder engine “range extender”.
Joe;
coal plant output is far lower than equivalent auto pollution per unit energy. It is far easier to work on plant smokestacks and burners. The “long tailpipe” argument is bogus.
Rad, can you give us more information about magnetic transmission? Transmission is the weak point of the Tesla (well, not so weak, but still).
Single gear transmission forces limited acceleration in cost of top speed or other way around, if we will ever get true EV racing car we need either huge RPM range for engine, or transmission that can cope with huge torque electric engine generates as well as huge jumps in RPM between gear changes. Magnetic sounds good, because there is no physical contact between gears.
Joe Simone, I agree that plugin hybrid has currently unlimited range and BEV doesn’t, but when battery tech advances and we get over 600 mile range batteries then things change. That range allows car to be driven nearly all day, and then charging time doesn’t matter so much because you charge at night. You don’t need to charge fully during long road trips (over 600 / day trip) if you can get about 200 miles in a hour, IE in your lunch break. 480V / 200 A would give you 96kWh worth in a hour or about 300 miles more. That is not too much, I bet any pizzeria with electric ovens has that kind connection to grid.
Also you need to consider that these “charging stations” will not really be “charging stations” because it just isn’t profitable. Too few cars charge in there. With 600 mile range over 90% of cars don’t use those charging stations at all. All you would need is slow charging pole in the place you usually park your car to eliminate need of charging stations. (that is one thing why I am against battery swapping, you simply don’t need it).
Even that US electric grid is somewhat outdated it can handle increased load from EV:s. There was a conversation about that not so long ago here in Tesla blogs. As you said nuclear is pretty clean environmentally, but solar and geothermal where it is available would be much better because those are clean and renewable (well geothermal isn’t really renewable, but it has nearly unlimited supply, much like Sun).
Have you guys thought of running the AC and radio of the solar panel that could be a part of the hood. I know the look maybe bad but it could improve the range while listening to music or running the AC.
At the risk of sounding like a conspiracy-theorist, I can’t help but point out that the GM Volt does more to diminish the viability of the EV than it does to extend its development. After reading some of the articles on the GM-Volt website, it seems that GM is using the inefficient Volt as a last-ditch effort to highlight potential failings of the pure BEV. The Volt is laughable at best, and this blog provides the data to make even the most rigorous skeptic a believer…
While Tesla’s achievements are laudable, there is a better solution than bigger and more expensive batteries. I’m talking free energy storage (really). Hint: gravity can be your friend. Dave Johnson, Power Zone Deployment LLC.
I am intrigued by the “spin battery” concept. Unfortunately, I do not subscribe to Nature Magazine, so I can’t read the whole article. Can anyone summarize this concept for me?
Also, perhaps you can elaborate on free energy storage Dave….
Here are some interesting facts regarding EV impact. The US consumes 390Million (per EIA) gallons of gasoline a day. Gasoline is mainly use for automobile travel. One gallon of gasoline contains 37Kilowatt hours of energy. This translates to the US consuming 14 Billion kilowatt hour per day in the form of gasoline for automobile travel.
Presently the US consumes (per EIA) about 10.5 Billion Kilowatts hours per day of electrical energy.
For now let us ignore the efficiency of converting “gasoline energy” to miles traveled and the efficiency of charging EV batteries and transferring the stored energy to miles traveled. These efficiency differences can’t skew the result that much. Now if we were to convert all gasoline consuming vehicles to battery operated vehicles we would need to draw another 14 Billion kilowatt hours per day from the power grid or about 2.3 times more energy than we currently draw.
Presently electrical power is supplied from 50% coal burning, 20% natural gas,20% Nuclear and 7% hydro and the rest from oil, wind and solar. I would guess the power grid probably has at about 50% extra capacity during off peak hours for charging EV batteries. That is almost what we need. However to generate full power from this underutilized equipment during off peak hours we will need to burn additional coal and natural gas. Nuclear plants probably have constant energy output. I do not think they shut them down during off peak hours. The question now is what is cleaner the coal burning portion of the electrical power grid used to charge the EV batteries or plain gasoline powered travel. . Electrical power generation from natural gas is relatively clean other than the CO2. Coal generates a lot of pollution and clean coal is a long way off:
www.ucsusa.org/clean_energy/coalvswind/c02c.html
If that coal burning energy was converted over to nuclear there would be no question that the nuclear would be cleaner than gasoline powered travel. Wind and solar represent about 2% of the electrical power generated now. We have a long long way to go before it becomes a significant contributor.
There are two issues one is pollution the other is energy independence. The US uses 20Million barrels of petroleum a day. It imports 12 Million barrels of petroleum a day or 60%. About 46% of the petroleum goes into gasoline after refining. I we would consume 40% of what we do now we would be energy independent and would not need to import petroleum. Of course the US petroleum reserve is finite and have to think of the future. If we cut automobile gasoline consumption by 40 % we do not address the other 54% (100-46) of the 60% imported petroleum products derived from the refining process. Some of that is diesel fuel, heating oil, lubricants and other products.
dave johnson, while it is true that you get quite a acceleration, speed and extremely fast deacceleration dropping Roadster from a crane, it isn’t quite feasible method of transporting people from place a to place b.
Care to elaborate what do you mean by “free energy”?
Timo,
We currently manufacture 100hp magnetic couplers for diesel generators…mostly to eliminate torsional and harmonic vibrations. We do have geared magnetic transmissions in use in Australia, they power solar pumps in remote locations. They are pretty efficient, in fact they are 99.9% efficient in transmitting power, that is 22% more efficient than gears. And they never break down.
So far the geared transmissions are only used at around 1000 rpm - low power, but the magnet holders are only made out of plastic. If we would switch to alloy holders and stack the discs, we could easily increase the power transmitted. We have a magnetic gear box drawn on CAD and so far the static tests look good. There are a few tricks we could use too, these are still on the “hand sketches” stage but the way things are going I wouldn’t be surprised if they would actually work.
Joe Simone, where did you get that 14billion kWh? If I calculate correctly that means that you have there in US 1.5 billion cars. Seems unlikely to me, even that you tend to have at least two cars / family, sometimes three. But I doubt that you have six cars per people.
Typical commute is about 40miles / day. 40 miles is one sixth of Tesla Roadster range. Roadster has 54 kWh battery so that means typical daily commute takes about 9kWh, lets say 10kWh. 14 billion kWh divided by 10kWh gives 1.4 billion cars. Should be about 250 million and even that figure is overkill, because some of the cars don’t drive every day. More like 2/3 of them is used every day. I get 1.67 billion kWh. Your number is nearly one order of magnitude bigger. Decimal point error?
Joe Simone: There is a very serious flaw in your argument, it assumes that both gasoline engines and electric motors are equally efficient, and they most definitely are not. A car powered by an gasoline internal combustion engine has a “pump to wheel” efficiency of about 15%. A car powered by batteries and an electric motor has a “plug to wheel” efficiency of about 76%, making BEVs 5x more efficient than gassers. Note that those efficiency differences are the same regardless of size, whether it is a truck, a big SUV, a sports car, or a tiny sub-compact.
So, switching from a transportation system using 14 billion Kwh worth of gasoline per day to all electric transports that uses 1/5 as much energy means it would use only 2.8 billion Kwh per day - a much smaller increase in electrical energy demand.
Also, coal fired power plants can use efficiency boosting devices too large for automotive use, their efficiency is arount 45%. So, between the higher efficiency of generation, the higher efficiency of the electrical grid (compared to truck and railroad shipped gasoline) and the much higher efficiency of BEVs mean that the electric option is still cleaner than gassers even when powered by coal, and the increasing use of renewables will make BEVs ever cleaner.
On another note, a recent Government energy report stated that California gets 20% of its electricity from renewables (wind, solar, geothermal), another 20% from hydro, and only 20.1% from coal. There is considerable potential for renewables to replace coal for electricity generation.
Hello! I’m a university student in Korea. My major is chemical engineering.
Nowadays, I hope to see your electric car directly. This is because I want to study this field after graduate school.
So I’m planning to visit North America to experience some of real knowledge such as hybrid car and the product made of lithuim ion cells.
By doing so, I can not only improve my study related in my majors but also approach to my dream.
Frankly, I wanna see and ride your electric car that would greatly impact on my life.
I see your car on TV, that was perfect and beautiful car that I ever have seen in my life.
So~~ could you allow to field trip your company just as a student?
Maybe I’ll visit America in August during my vacation…
best regards..
I have a solar multipanel 900 watt charger that is just DC to DC, direct connection, not using the Tesla AC charging box. Is this something that other owners would be interested in? It charges faster due to no loses and minimal components. It could be useful for having at work to charge 1 or 2 Tesla’s during the daytime. Just wondering…
CM: You are correct. I ignored efficiencies differences thinking they would be a wash. But looking at it more closely the roadster consumes 199wh per km or 5 meters /wh. A gasoline powered auto getting 25 miles per gallon with 37 kwh per gallon of gas yields 1.1 meters/wh. That is the 5 to one difference you claimed. It indicates the need for only 2.8 billion Kwh per day of additional energy off the present 10.5 billion Kwh per day grid. That is a very encouraging result and an endorsement for the future of electric powered vehicles. Thank you for the correction.
This also probably explains the discrepancy Timo noticed in checking the conclusion in a different way.
Does Tesla have any plans to use solar cell technology with their cars to constantly charge the battery while driving? Also, do you have a generator that creates a charge while driving on battery to give longer life to the battery charge as well?
Thanks you!
Jack
Just out of curiosity, is Tesla considering the possibility of incorporating solar power generation components? What interests me in particular are the advances in dye based photovoltaic systems such as those being demonstrated by Dyesol. I have read a few articles regarding the development of transparent solar cells for use as replacement windows (see: www.inhabitat.com/2008/04/14/dyesol-solar-windows/). For safety reasons, I’m sure such technology would not be suitable for use on side or rear windows nor windshields, but the Model S prototype features a sunroof that has a fair bit of real estate. Then there is the solar paint idea… but I’m not sure I would sacrifice the visual appeal of a nice paint job for a few extra watts of power. I’d have to see a sample first.
GW
Jack,
If the power system in the Roadster is anything like the battery power systems I have worked on in the past, then it is not possible to discharge the batteries (driving, using electronics, etc) and charge them at the same time. The current used to charge the batteries flows on the same conductors used to discharge them, so the net current results in discharge OR charge. However, solar panels might be able to provide parallel current, thus reducing the energy demand from the batteries and effectively increasing range.
I’m not as knowledgeable as I would like to be when it comes to the technology of our future electric cars, but I was wondering if there is any talk about maybe using different conductors for charging and discharging. I have a couple of good ideas that would basically make so much energy, you might be able to have a surplus. I’m not sure if it is even possible to make a car charge while discharging, but if it is let me know!
The subject of solar cells comes up frequently. Tesla is correct in stating that the return on investment for solar cells on the car is almost zero. They recommend you put solar cells on your house or garage and use that to charge the car. They have a working agreement with SolarCity and there is a link in the left hand column.
Matthew: Hybrids like the Volt do generate electricity to charge the battery while the electric motor draws power. To put a fine line on it, it does not charge and discharge simultaneously, but generated power goes directly to the electric motor and any extra charges the battery. If the demand is greater than the generated power, then all generated power goes to the electric motor plus required extra discharged from the battery. I cannot conceive of any way to improve on this system. Let’s say you have two batteries, and the generator charges one while the electric motor uses the other. This would be less efficient than the standard arrangement as there are energy losses in charging and discharging the battery. Read Something for Nothing in www.teslamotors.com/blog2/?p=24
Jack,
Great work! I believe that this is the future. I’ll admit I haven’t read all of the posts so you may have covered this already. I’ve always been interested in the use of the energy produced by the wheels. You essentially have four generators producing energy at all times. You could draw from the wheels power as well as the battery delivering the necessary power at the relative speed. I would imagine the higher the speed the lower the draw on the battery. With a unique gearing system you may even be able to generate enough power with the wheel generators at relative speeds to deliver enough power , separate from battery power, to sustain drive indefinitely.
I also like the idea of a hood scope or grill scope which would turn a wind generator under the hood. This generator or numerous ones could power accessories saving precious battery power.
Actual Trip time:
I would like to see a graph posted showing the time it takes to travel a given distance with the 45 minute charges included. For example, it takes x amount of hours at 80 miles per hour to travel 500 miles because the are 3 charges required, vs x amount of hours at 55 miles per hour because there are 2 charges required.
Jack: Those are the exact same 2 ideas that I was thinking about! I would think using hub generators would be a great way to drive for “free” basically. The only problem once that happens is how the roads would get fixed since there would no longer be people paying taxes for gasoline which is what is used to repair the roads now.
Andrew May: Wheels don’t produce energy, but they can be connected to a generator that converts the forward momentum of the car into electricity, slowing the car down. That’s how regenerative braking works. Tesla Motors has a clever way of converting the electric motor into a generator whenever the car needs to slow down, and that partially recharges the battery. However, it just wouldn’t do to try and drive with the regenerative brakes on all the time!
As for the “hood scoop wind generator” idea, its been proposed hundreds of times before. You’ve underestimated the amount of drag it would produce and you’ve overestimated the amount of electricity a tiny wind turbine can produce. The increased drag would drain away more power than the wind turbine could produce, reducing the driving range. Sorry, its a step backwards. Much better to put the wind turbine on a tower at a windy site where “wind drag” doesn’t matter.
Andrew May, any wheel-mounted generator works like brakes. Electric energy is not free, and generator is just engine working another direction, so all electricity it generates slows car down until it does not move. Same with grill -scope mounted wind generators. Those cause air drag which negates the electricity generating effect entirely and then some.
And because there are no 100% efficient generators/gears/wires etc. you end up losing power.
Wheel-mounted generators can be used to regenerate energy while braking, that’s all. For rear wheels Roadster already does that, and I believe Type S in 4WD -configuration does that with front wheels as well. You still lose power. Overall efficiency making car move is something like 80% so you lose 20% in making car move and another 20% from generated energy so net gain is only 64% (20% out of 80% is 16%). Perpetual machine would require 100% gain or more.
This company is exactly what the America needs.What I have read ,I hope to see this company go far.My question to the engineers is this; is there a way to connect a generator to the main motor so when the battery charge reads (a) certain volt(s), the circut to the generator closes starting the generator and opens the circut between the battery and the motor closing the circut between the generator and the battery? With the generator producing electricity sending it to the battery,can the motor in turn be used to produce its own power for a time or receive power from the generator.I did use generator and not alternator because I understand that this is direct current power.Thank you and may your success continue to grow.
I just skimmed through the site this evening, if this was already discussed, forgive me. This is something that I thought was discussed a few years back in designing the batteries for the roadster. If the battery was removable like a heafty suit case (or as 3 or 4 smaller modular suitcases) that you could stop after 200+ miles at a location (set up agreements with a chain of service stations of truck stops) and pay a nominal fee to have the ESS swapped out for a fresh one and continue on down the road.
I thought i remember the idea that the battery cells would be owned by Tesla and exchanged toward the end of their life (treated kind of like a 5yr lease, $1000/yr. The first 5yrs comes with the purchase and come in for 5yr service which will include pulling and testing each cell and replacing the ones that are showing signs of failing, and pay the $5k for each 5yrs.) Wouldn’t that work out with this swap out service? The services would be tracked electrically, I expect the cells each have serial #s and each cell is entered into the database when they are installed, and since you are paying for a 5yrs of battery life it doesn’t matter which ESS you have at the end of the time. It would kind of be like taking and exchanging your empty propane tank for a full tank, you pay more than having yours refilled but it saves time. In this case it would extend your range, to almost unlimited or atleast daytime hours if you can’t find 24hr locations that can perform the service, once a full network of locations is established (as long as the proceedure can be done by most service techs).
I am not sure this how feasible it would be in looking at the ESS and not knowing the way it is installed. As it is half the total weight of the car in one piece it might be a bit of a problem. But I am thinking of places like a Tire shop [i would say the name but I don’t want to try to advertise on your site.. Les Schwab because they are are a full service repair shop and handle heavy equipment tires, also they are all over the west coast now. please deleted this bracketed portion for posting] that hadles heavy equipment tires, they would have no problem with a lightweight item of only 1/2 ton. Maybe it is something to think about for the future design. It really would be nice if you could pull up to a ESS swap station, go inside and pay for a battery swapout and come back out and drive away that would give the marketability a huge boost, range is always the complaint that people give as to why EV aren’t feasible. It wouldn’t require a large number of locations, it would mostly be for travelers. I am in Northern California; I am thinking one station along Interstate 80 coming into West Sacramento from SF. Then one along 80 up around Roseville or Rocklin and one along 50 east of Sac maybe Folsoml. Then maybe Reno, South Lake Tahoe, Carson City. Another near 580 and 5 intersection, then south, Fresno, Bakersfield… just place them at strategic locations that are easily accesable from the Interstates. South of San Jose along 101.. Monterey.. etc. North of SF then Willits Eureka. With about 25 locations you could get to most anywhere in California with a fresh battery. Then add stations along the way to Vegas from LA, and Bakersfield to Vegas!
This leads me to the question that has been nagging me for years now. How significant is the effect of grades on battery life? If you attempt to drive over Donner Summit to Reno how far would you get? I would be interested to see the wh/mile and range/speed graphs on 2%, 5% and 7% grades. I am assuming that the graphs posted are all at 0% grade. I know it will drop but I am burning to see what the numbers are. I know that driving from Reno to Sacramento uses much less fuel than going from Sacramento to Reno because of the elevation difference. Much of the way from the summit down to Sacramento you normally use brakes, in the Roadster I wonder if you would end up with more of a charge by the time you reached Sacramento than when you left the summit with. The only item that will change significantly is the drivetrain power consumption. Aerodynamics and tire draws wont be effected significantly. A load test on a dyno, setting the load to simulate the added wieght effect of climbing the grade should give a pretty close estimate. Maybe soon we will will start seeing some real world experiences posted in the blog. Also how much is the additional draw from driving at night? How much does that add to the ancillary draw? And running the heater and A/C on max? Defroster data should work for that if the A/C is used to remove moisture from the cabin. It would be nice to see a graph showing those effects too.
The other option is quick charging stations, pull up to the quick charge at a location and plug in. I think most places would allow you to install a charging station probably without any monthly fee, just for the good PR and ability to advertise they have one, the bigger problem would be with potential vandalism; they will have to be locked up during non-business hours. You can walk to a restaurant for lunch or do a bit of shopping and come back about an hour later to most of a charge. It would still be a selling point.
This might be addessed on the site already, again I apologise if I am repeating information already offered. I am wondering why the plug couldn’t fit a standard 220 outlet? Many people have 220 outlets in their garages and in their laundry rooms. I guess the issue that I see is that if you plan on moving and the charging station is hard wired into your house you need an electrician to come and remove it and re-install it at a new site. If I could simply plug the charging station into a standard 220 outlet on a 100 amp breaker, it would simplify things. It could still be mounted on a wall, just with the cord plugged into the side or bottom of it. Why not have the charging station fit with a 220 outlet that can be used instead of having it hard wired in? Is there a reason that it cannot? Other than some people might try and run a long extension cord to the charger and burn the unit up. I am also curious, are many people using the portable chargers? I would like to see what kind of experiences people are having using them.
Thank you to all who have put in so much of yourselves into Tesla Motors. I had thought of trying to work for Tesla but I don’t see how I can afford to live in the Bay Area… unless you let me sleep in the office (and have showers in the office.) keep up the good work, wish I could help. I was glad you were able to get another $40mill to keep things moving forward.
Does Tesla have plans to incorporate the new Nano Ball Lithium Ion battery technology from Toshiba that could potentially recharge the cars batteries to 80% in minutes? (see en.wikipedia.org/wiki/Nanobatteries).
And is the company looking into technologies that recharge the car while driving such as the MIT Genshock (techfragments.com/news/415/Tech/MIT_Team_Creates_Shock_That_Recharges_Your_Car.html) or regenerative braking?
I believe that I would be able to prove how you can regenerate your own electrical powere without the use of plug ins.
The car will regenerate its own power. If Have an interest let me know.
Hello Gentlemen;
I love your work, I hope for a day I can afford your product. I write this today because I have had ideas that I can not afford to pursue myself. I just wish to give to the society in which I live. It may have intellectual property value. My perception of the current issues related to your type of products is the use time is quicker than the charge time. I have seen and try to keep up with the chemical and electrical battery side of leading science but find it could be awhile. I have a varied background and do not have the credentials of anyone I have read on here. The varied background crosses several industries and as a result has lead to some crossover thinking.
I believe using the Bernulli principle in combination with permanent magnet motor/generator placed in a vehicle where the accelerated air was then applied to the generator via helicopter blading that had been calculated to offset the weight of the generator and exit the air into the vertical that it would not add exceesive drag.Also with simple helicopter blading (i.e. maintain blades attached to the generator in autorotative condition and constant rpm via pitch control ) you can have an onboard charging system that would at the very least extend your range further.I hope your engineers will review this idea. The lift equation can be used to calculate blade size to offset the permanent magnet alternator/generator weight. Your design easily would take on wind scoop to venturi portion of the system.An electrical engineer can do the math on what the neodymium magnets spinning all the time can do for you. Also if you changed that a bit more and ran with a Halbach array for the magnets in the generator you may not have to wait on the battery science. I wish you guys the best and I am sorry our on government is sabotaging your business bailing out the old school guys. Have a great day. Hampton Price
I like what I see so I am asking these questions. If wind turbines can generate electricity, then why can’t an automobile be designed that adapts that principal? Batteries need to be recharged. If a company like yours designed a vehicle that adapted wind turbines in the vehicle to re-energize the batteries as you drive then there would be no need for gasoline or grid. Adapt a battery pack that runs the vehicle and one that stores and transfers energy to the other batteries as you drive. Jet engines draw air into the intake. If the grill of a vehicle were to designed to bring air into the vehicle as you drive to run a turbine and generate energy to a back up battery pack, then that battery pack could be used as a reserve. Hence, after the energy in one battery pack gets low, just switch to the other and put the first battery pack on the turbine. I’m just guessing here but the theory sounds possible.
Thank You,
Dennis McCuneo
P.S. If not a wind turbine, then why not utilize the wheels to generate that ebergy to booster a second battery pack?
Curt Helland, Tesla is continuously checking new technologies for batteries and selects what is best compromise between price, reliability and energy density. They might not be using best batteries tech-wise but they are using a very good compromise.
Those MIT Genshock shocks generate very little energy. They generate some, but to keep things simple, I’d prefer reliable and cheap ordinary shocks. I think best way to “charge while driving” would be using inductive coils under pavement (another MIT/Intel invention allows wireless energy transfer up to 75% efficiency to one meter distance). Unfortunately this would also increase road maintenance costs a lot, and it brings up a question how to determine who charges his/her car and how much. Also because car is using quite a bit energy while driven it might be that those coils might not be viable source of energy. Roadster uses 13-14kW at highway speeds. That is quite a lot of energy to transfer wirelessly.
Hello JB,
As the photovoltaic technology improves ( www2.dupont.com/Photovoltaics/en_US/ ) are you guys looking to use this on the cars so that they could be “charged” when light is shining on the car surface(roof/windshied/body) ? that would be a natural range extender for the tesla cars could get more tac breaks for the customer whne buying and savings when using.
CW
To all that suggest wind generators to get indefinite range, just try it yourself. Build a toy car with electric engine and windmill in top of it. Spin that windmill blade with your hand to get initial boost to electric engine and see yourself how far your car goes.
We can’t create energy any more than we can destroy it. We can ONLY convert it to different forms. In batteries energy is in electric potential. There that potential it is transferred to electric motor which converts electricity thru magnetism to kinetic energy. Windmill converts kinetic energy to electricity, but *there are always losses* NEVER opposite. Otherwise you are talking about perpetual motion machine. IT JUST ISN’T POSSIBLE. You could get some energy from actual *wind* (not that air displacement that car causes when it moves like people here suggests) using sails if wind is blowing from behind, but I don’t think you want sails in fast sportcar.
So please just stop it.
Lets explain a bit further why windmill in car can’t work.
As I in previous message wrote we can’t create energy we can only convert it.
Where does energy windmill generates come from? From air movement. In other words windmill slows that air movement in order to generate energy, and that generates air drag.
Where does that air movement come from? Air displacement from car movement, which in other words is air drag. Car makes work in order to overcome that air displacement.
What that windmill would actually do is generate electricity from work done by the car, and as so causes more work for car to do. With 100% efficiency in energy conversions you end up +- zero gain, but because there is always losses in energy conversions you end up losing more than you gain.
So, at best you could get absolutely nothing, but in practice you would end up losing energy.
AND, in order to generate as much energy as car uses you would have to capture *entire airflow* car causes when it moves thru air and then some, because you wouldn’t be capturing energy used to overcome rolling resistances and ancillary losses.
Timo;
In a way it’s kind of fun to try to explain to the free-energy doofi that TANSTAAFL, but it’s kind of a waste of time. They have a deep intuition that if they’re just clever enough they can cheat physics and arithmetic. I suspect childhood trauma, probably causing lesions in the left temporal lobe.
Brian H;
I know. For some reason I enjoy that even that I know it is futile and pointless. I exercise that same in other forums as well. ….I think that makes me masochist of some sort…
I had an idea. If you put generators around the axles you could generate some electricity when you accelerate. You would simply be turning some of the mechanicle power of the car into electricity. Im not sure if this would be good enough to keep a batery charged but it could help.
Hampton Price: Aside from the safety and legal aspects of having a helicopter roter (actually, an “autogiro”) on the roof of the car, it still creates more losses due to drag than the electricity it could generate. Any lift generated would also create additional drag, and could possibly cause handling and stability problems. Permenent magnet motors are no more efficient than the induction motor Tesla is using, but they are more expensive. Halbach arrays are great on special tracks for mag-lev vehicles, but are useless for road vehicles.
Dennis McCuneo: Yes, wind turbines generate electricity, but it takes a really big wind turbine to generate a substantial amount of electricity. One small enough to fit on a car wouldn’t do much. Worse, it creates air drag, which is why wind turbines have to be mounted on sturdy towers. That drag forces the drive motor to use more electricity, more than the tiny turbine can produce. Sorry, it would actually reduce range.
Nathan: Generators convert mechanical effort into electical effort, so your generator idea would slow the car down just like applying the brakes, that’s what “regenerative braking” is. That’s great when you’re trying to slow down, but really bad news when you’re trying to accelerate! Sorry, generators and motors are not 100% efficient, so having your drive motor fighting to accelerate the car against the regenerative brakes would only reduce the range - and make for really lousy performance!
Timo: Nice to see another “explainer” out there. Scientific illiteracy does seem to be an ongoing problem.
I just read that your factory is planning to produce a gas electric car. It is disappointing to hear that that because your factory is the leader in electric vehicles. I have also read what inconvenient can be a gas electric compared with and all electric car, that someone says your company posted in your home pagem, and it sounds contradictory.
However, if you are planning to move into gas electric vehicles, why don’t you use a compressed air motor instead, just like the one designed in Australia, to drive the electric generator? It is small and can move a heavy load.
pesn.com/2006/05/11/9500269_Engineair_Compressed-Air_Motor/
you are making the best and nices cars in the world.
my best regards, hopping your company gives more good news to the world.
are tesla aware of new battery technology from MIT that allows a LI-ion battery to be charged in 30 seconds as opposed to 6 mins for a “modern day” commercially available battery. There’s a link here technology.timesonline.co.uk/tol/news/tech_and_web/article5891194.ece just in case.
Brilliant cars btw.
Is that Nathan for real? We have had a Nathan who made sane comments earlier; maybe he was just trying to be cute here and give us an example of the witless reasoning of the free-energizers?
On the off chance that it’s serious: Nathan, your suggestion is about as smart as driving with the brakes on to generate heat to boil water to turn a steam turbine to turn the wheels to generate heat from the brakes to boil water to …
have you ever thought of putting some type of generator in the wheel wells to create power 4 the battery?
fabian;
See the comment immediately preceding yours.
Eliuth, you were misinformed. Tesla Motors once had considered making a “gas electric car”, but after seeing the improvements in batteries and all the problems inherent to gas engines, they decided to continue developing pure battery electric cars only. Their planned Model S has no infernal combustion engine and no gas tank, which leaves room for luggage both in front and in back! The base Model S should have a 165 mile range per charge, but extra batteries can be added under the floor to increase range up to 300 miles, and they can be fast charged in about an hour or “swapped” for fully charged packs for drivers in a hurry. That’s a better solution than a “range extender” engine.
Tesla Motors is not considering compressed air engines, either, the energy density of compressed air is far less than the batteries Tesla is using, and the efficiency is lower. Compressed air engines might be suitable for short range slow speed vehicles, but a long range “air car” would be mostly air tank! It would be a very bad choice for an EV “range extender” generator, the air tank would be larger than the batteries but would hold less energy. Better to use extra batteries.
fabian alt: Have you considered reading the previous posts? Tesla Motors has already figured out how to switch the motor to be a generator, the car does that only when the driver wants to slow down. It’s called “regenerative braking”. It just doesn’t make any sense to try and drive around with the (regenerative) brakes on!
I notice when I am in the mountains, I have a lot of up hill driving, and then a lot of down hill driving. When you go up hill, you would use the normal battery power to move the car. While going down hill, because of the inertia of the car going down, by energizing two DC Generators, one in each wheel, you would be using the inertia of the car going down hill to charge the batteries. This is a little like regenerative breaking, where you generate electricity when you put on the break and slow down, but different in that you use the inertia of the downward pull of the car as your car travels down hill for 1/2 an hour to an hour, to charge your battery pack, thus use the generated power going down hill, without use of breaking, to charge. Existing cruise control devises can be put in place on your downward direction to control your speed, as so you don’t have to ride the breaks all the time. When the car leveled out, those generators would be electronicly turned off, and they would be in free spin mode, creating little or no drag on the battery system, other than the actual weight difference of the casing of the aluminum generators, and windings. The more passenger weight you have in the car, the more electricity generated on your down hill quest. With this type system, you still would have to charge on occasion, but less often. If you took a short straight freeway to the top of a hill where you work, and then took the lazy windy downhill road home, that took you 1/2 hour longer, you may never have to charge your car, or at least less often. By utilizing a 240 or 480 volt generator, you would recharge the batteries quicker than using a 120 volt system. Your batteries are literally in charge mode as you coasted down hill, and would not be used but only charged by the inertia. This is a little like an electric light, attached to your wheel on a bicycle. While you are pumping along on the level you need to use the battery or your legs to pump the bike, but the light is on all the time. When you go down hill, you no longer have to pump, but just coast for miles ,and the light works all the way down the hill, using the inertia of the weight of the bicycle to generate electricity to propel you along, and light the way. If you have ever ridden a 10 speed bicycle down the Feather River Canyon in the Sierra’s, you are shocked that you can go almost all the way by coasting. Can you imagine how much power can be generated on that down hill ride, that could get you farther on your way when you get to the bottom. This is not an example of free energizing, but of using the inertia of the weight of the vehicle to run a charging system to increase your distance between charge.
Has Tesla Motors ever published on-road performance tests of their battery packs to end of useful life of the packs”? If yes where can the public read the results? Thank you..GC
“CM wrote on April 4th, 2009 at 11:56 pm
Joe Simone: Tesla is currently using a 54 Kwh LiIon battery pack with a cobalt oxide cathode with higher energy density and a lower cost per Kwh stored. The GM Volt will be using a smaller 16 Kwh LiIon battery pack with a manganese spinel cathode, the energy density is a little lower and the cost per Kwh stored is higher, but since the battery is a lot smaller the total cost is lower, but because it is smaller it must withstand 6 times more charging cycles to go the same distance as the Tesla Roadster, and it does.
The result is that Tesla and GM are using radically different approaches for plug-in cars, and that requires different batteries.”
In an article about Tesla gas electric venture they indicated the need for a different battery technology than the all electric. What is the different characteristics required of a battery in a gas electric verses an all electric other than smaller KWH storage for gas electric.
Has Telsta Motors ever published on-road performance tests of their battery packs to end of useful life of the packs”? If yes where can the public read the results? Thank you..GC submitted 05-04-09
Ronald Wose, what you describe is basically regenerative braking which Tesla already has. Tesla approach is not using actual brakes for regenerative braking, but “engine brake”, so if you lift your foot from the gas-pedal you switch on regenerative braking. IOW this behavior you suggest is automatic in Tesla configuration.
Type S in 4WD configuration might be even better in that, because it can use more active braking with front-wheels too. I wonder if they have regenerative braking also from brake-pedal in Type S, and ordinary friction brakes are used only with very high deacceleration needs (kind of emergency brakes).
Response to: Ronald Wose wrote on May 3rd, 2009 at 5:09 pm
First of all taking a straight freeway to work and then taking a downhill run to go back home is not possible. The straight freeway must be going uphill from home however gradual in order to go downhill to go back home. In going to work you are gaining potential energy by going uphill. The battery is being drained to provide this potential energy as well as surmounting the friction and wind resistance of the travel. In going home downhill this potential energy can be tapped to charge the battery to recoup a portion of the energy used to provide the potential energy gotten by going uphill to work. A portion of this potential energy will also have to be used in surmounting the friction and wind resistance of the downhill run. There is no net gain in going uphill and then downhill.
YOU EXTRAORDINARY PEOPLE, GREETINGS!
WHERE WERE YOU RIGHT AFTER WORLD WAR II, DEVELOPING YOUR CLEAN BEAUTIFULL CARS AND REPOST STATIONS ALL OVER.
IMAGEN HAVING LUNCH IN A LONG TRIP WHILE YOUR CAR GETS RECHARGED IN ONE OF THOUSANDS OF “RECHARGEDINNERS” OF DIFERENT MENUES ALL OVER A CLEANER WORLD WHILE OIL BE DEDICATED TO NOBLER CAUSES LIKE FERTILIZERS AND OTHER NECESARY PRODUCTS!
WE WOULD LIVE IN A DIFFERNT WORLD.
i NOW LIVE IN CUERNAVACA (MEXICO) AND OFCOURSE THERE’S NOT A SHADOW OF YOUR GREAT AND BEATIFULL PRODUCTS AROUND. HOW MUCH WOULD COST TO BECAME ONE OF YOUR BRANCHES (SALES AND SERVICE) IN MEXICO?.
ONCE MORE, I, FOR ONE, LUST FOR A COUPLE OF YOUR CARS, A ROADSTER AND THE TYPE S…
The Future is allready here, just look arround, Portuguese Cientists invented The “Ion Jelly” I Think this would be the secret to obtain real good bateries.
is it possible to show the consumption of energy allong with an addiditon of energy from a thin film solar panel that is working at a possible efficiency of eighty percent of max for that panel? additional juicing in the middle of driving could enhance range so would it be possible to print the film right on the exterior body parts?
HI,
As aerodynamic loses are such a factor at high speeds any idea how much drag is caused by wing mirrors? You could using cameras and screens instead obviously this would be matched by a small electrical cost.
Ta
Paul
The future is electric cars, yes we can.
I wonder how much range improvement you could achieve by adopting solar cells on the surfaces, and in particular by fitting the car with energy recovering suspensions (from induction coils) from the continuous up and down movement while driving. They could also be used to improve the handling at high speeds (like using adapted Bose suspensions).
I have seen that Brabus has “copied” my suggestion about sounds I posted a few months back!
Edmund, It is possible to use thin film solar panels in car, but energy gain from those is minimal and cost is high. Even at best case you would be getting something like 1000W/m^2, and thin film solar cells have about 15% conversion rate, so with 3m^2 of panels in car you could get max 3*1000*0.15 = 450 W. That is the best case. In practice you would get way less than that. Roadster uses 15kW at 60mph, so you would give it less than 10% increase in expense of high price paint job. In practice less than 5%.
It would be better just to put better batteries in car. At the roof of garage that thin-film solar cell would serve better purpose.
I have sometimes thought about very large folded thin-film solar cell in car trunk that you could unfold as a kind of tent for that car when you park your car for a longer times in places where there are no electric plugs where you could charge your car. That would cost quite a lot, but could be useful to get your car charged “on road”. Even if it could give only one kW of power you could get few miles out of it during a day. 10 hours would give you about 50 miles worth of charge.
Apparently mathematical part of my brain is on vacation.
450W out of 15000W is 3% and that would be less in practice.
To MrClean: Energy you could get from energy recovering suspension is at max tiny part of rolling resistance loss, so in case of Roadster you could get tiny part of 25%. My guess is that it would be similar to solar panels: not useful amount. On the other hand, if they are better than ordinary suspension _as a suspension_ then it might be worth using them.
This company will do much better in EU (or Japan) than in USA because of smaller distances between cities and gasoline price. Next good think for Tesla in EU is 220-240W power supply system (hopefully one day US will switch on this system too). Also EU people like small cars because of chronic lack of parking space and presence of narrow streets. From experience a can say that Europeans are concerned for environment more than Americans. (Californians developed strong environmentalist movement, but rest of US is really ecological “retarded”;-( ).
However, it is puzzling why the EV concepts never get life in Japan, EU or even Israel (even these countries have more reasons for EV development than we are, at still all aspiration to do so were immediately stopped in begging of development).
I have seen many improvisations in the third world countries in the term of developing the alternative source for car powering. Probably the most successful is use of bio diesel in Brazil, alcohol in Cuba and primitive models of EV buses in India.
Natural gas is getting very popular in EU lately. It is cheaper and more environmental friendly than diesel and gasoline. (This concept was successfully developed in private garages in Balkans during a war, it pouffes chipper and safer than a regular gasoline module).
However EV is king of all concepts so far, it is our future and it should spread all over the world. In the term, this to be done, EV should be much cheaper than it is today. Hopefully we will see muss production of EV-s oversees soon.
p.s. Since, the graph shows an air resistance as the biggest enemy to EV’s durability i would like you to think little bite how to reduce it. For instance the shack skin concepts seems interesting idea.
www.wired.com/science/discoveries/news/2005/03/66833
www.autoblog.com/2008/06/10/bmw-gina-light-visionary-model-revealed/
Fabricate the roof of the a solar panle, while it is being driven in sunny states, your range is greater, and while it is setting in the sun all day while you’re working, you are not using power from the grid, only at night and if it rains you would need to plugging. (Because the solar panel will generate electricity, while moving or standing still) prove me wrong.
A good test is, take one you have now, and modify one like I said and see which one goes
Further.
Calvin Jones; yes you are right, you get a bigger range with solar panel roof…about 1% bigger range for very good case. If you park your car in parking slot in a sunny day you might even get 10% more range in ten hours.
Solar cells are much better used in buildings and solar power plants than in cars. Assume there is 30 cars in parking lot in typical office building, which is as large in sideways as the parking lot and is square in shape with usable roof for solar cells about 30% you get about 3600m^2 * 0.3 = 1080m^2 surface area compared to about 30m^2 surface area in those car roofs. Use that power to those cars and you have much better kW for charging.
Solar radiation is about 1kW/m^2 at a good sunny day. Cheap thin film solar cells give maybe 10% efficiency in converting it to electricity. That’s 100W /m^2. 1080m^2*100W/m^2 is 108000W or 108kW. Divided by 30 (cars) gives 3.6kW / car compared to about 100W / car. With the price of $3 / watt you get $300k for those panels. Divided by 30 car owners you could get $10k to pay. You could divide that to several years, maybe five to reduce it to $2000 / year or $166 / month.
For typical office day you can then charge 36kWh in your car (worth maybe 100 miles) and rest of the day you can sell that electricity to the grid. You might actually start to *gain* some money after a while, because not all cars charge that much during a day. Your office building becomes a power plant.
BTW nanotech is again showing interesting development in this field as well as batteries. I just read about solar cells with nano antennae that can convert *80%* of the sunlight to electiricy and it would theoretically even be cheap (can be produced using printing tech like newspapers are made).
Mr. TIMO
My previous information on LITHIUM AIR CELL invented at AIST had to be clarified a little more.
Realized energy density 50,000mAH/g where refferred mass g is not a total weight of the battery
but the mass of the definite AIR ANODE .
So, the masses of the LITHIUM METAL CATHODE and other structure is not clarified in the news contents.
So, real energy density is significantly reduced.
The main success info of the said news contents is that inserting the LI conducting barrier
between the ANODE and CATHODE electrolyte realizing the continuous reaction at the ANODE
by preventing from the sourcing of the harmful solid chemical component to the ANODE.
I am also unaware how many recharging cycles have been is established in the news contents.
If LITHIUM AIR CELL remains as a kind of FUEL CELL by only consuming the LITHIUM METAL,
it is not practical for EV, It must be realized as a rechargeable battery.
Perhaps it must be a hard technology.
By the way, last year , TOYOTA announced that they will develop METAL AIR rechargeable battery
as a battey to be adopted in future TOYOTA car.
Type S FAQ talks about fast charging and says that car can be charged to 80% as little time as 45 min. Which battery pack? Smallest one? Any specs about that charger? Cost?
80% out of 160 miles is 128 miles. 80% out of 300 miles is 240 miles. Am I right if I assume double time for larger battery pack? 1.5 hours? 540 miles is close to breakpoint, but it would be better if you wouldn’t need to charge at all before 600 miles.
In one of the media pages someone (forgot who) says that Model S has 85 kWh battery pack. Since that is 37% bigger battery pack than Roadster battery pack and Roadster can go 240miles I assume that one was 300 mile version? 80% out of 85kWh in 1.5 hours needs 45kW connection. That is quite huge connection. Charging page says it can be charged with 480V so that gives roughly 94 amps. No household connection to grid can handle that, so how has it been made? Battery to battery charging? If so, how large is that charger? Which kind of batteries? Can those be upgraded? How much it costs?
Awesome post! This is very informative, though I must admit, I’m still a little lost on some of this stuff. But POWER, that I can understand…
I am still waiting a response to my question…
Has Telsa Motors ever published on-road performance tests of their battery packs, testing end of useful life of the packs”? If yes where can the public read the results?
I will rephrase my question.
Has Telsa motors ever completed on-road tests of their battery packs to end-of -useful-life. Where can we see the results?
Lab testing or even simulated road testing does not represent the real world of driving the EV, until the batteries fail to deliver the published 300 MPC or the 240 MPC.
My second question:
How does Telsa charge their battery packs to 80% SOC in 45 minutes.
That is impossible to do using a household power grid connection. So when a person buys a Telsa EV, what does Telsa suggest they do to get the vehicles charged to 80% in 45 minutes?
Take the EV to a specially constructed 480V connection ….but where are these connections.
One may find them in SKY Harbor Airport in Phoenix where they fast charge EVs for service work on the airport.
I can gas-up my Honda Ridgeline in less than 5 minutes to get 370 miles before my next 5 minute fill-up.
Third question:
How long to charge Telsa battery packs to 100% SOC.
I am flabbergasted that none of the financial supporters of Telsa have not asked or demanded answers to critical issues of useful life of battery packs, and fast charging.
All the marketing hype in the world will not sustain any product when customers discover its short comings.
The EV graveyard is filled with high flying EV start ups, including GM’s infamous EV1; they produced 1170 EV1’s, and leased them. But finally took them back and crushed them.
Fourth question:
Where does Telsa publish the “cost of maintenance” for their EVs, for example replacement battery packs, wear and tear and repair due to accidents.
I only wish Telsa great success. But unless Telsa can provide more real world performance testing on their battery packs, then down the road they will find plenty of room in the proverbial EV graveyard.
GC
Galactic Cannibal; Tesla has driven its Roadster prototypes hundreds thousand miles and no correction has been made to promises, so I’m guessing that battery pack delivers what it promises (which is 100k miles or five years of useful life).
Your second question is for Type S. Roadster battery pack is charged from empty to full in 3.5 hours. There is no “fast charging” for Roadster (unless you count that 3.5 hours fast charging).
Remember that Type S is still prototype. Things are subject to change, so no exact values can be promised. Battery pack depends of how fast they get to mass-produce Type S. If it is late, battery tech gets improved, if early then they go with a bit lesser techs.
I haven’t seen “cost of maintenance”. I’d expect it is about what usual car would be, except that you will never have to repair or maintain your engine, and your brakes are saved quite a bit by regen braking. Suspension, tires, wear and tear are still same, there is no miracle tech to remove those. Because Roadster is luxury car you can expect a bit higher cost for quality repairs, but quality would be excellent.
EV battery pack can never be charged as fast as you can fill a gas tank (just basic physics) unless you get some superconductive wiring to do the trick in distant future. But who cares if you can drive 600 miles with single charge (tech to that is very near finished), and while having your lunch break you get charged to 200-400 miles more. That is whole day worth driving. And you can start every day with full charge.
Just like solar photovoltaic cells, battery tech improves fast, really fast, and while doing so prices go down / kWh battery pack can hold. Soon you can get battery packs with 500-700Wh/kg energy densities, which means Type S 300 mile 85kW battery pack times two (600 miles) would weight only 340-240 kg and take space about same as your current gas tank, and it is not stopping there. A bit further away are techs that can deliver over 1.5kWh/kg. Era of gas guzzlers is over, what you see now in roads are last remnants of obsolete tech.
People on this blog have mentioned battery to battery charging and high grid power charging. A better way to do this would be capacitor to battery charging. The capacitors bank could slow charge from the grid and quick charge to the battery rapidly speeding the recharge time. While not ideal for home use it is great for recharge stations which could use a combo of wind and solar technologies to slow charge the capacitors. This method would solve many of the range problems of EV’s and could start as a slow moving infrastructure expanding from each Tesla dealer much like the marriage of the big three and big oil. We could have big EV and big wind& solar. this could happen soon here in the US if the politicians could uncover their eyes and become less greedy.
The best way for people to make a difference is to work at the local level to create the infrastructure need for Tesla and other EV makers to grow.
Joshua Maxwell; I’m not sure how you would benefit from low energy density expensive capacitors compared to batteries. Care to explain further? If you think that batteries can’t deliver enough wattage you are just wrong. Anyway, absolute limit is set by car-side of the batteries, not charger side. Car can’t accept very huge volts and amps without converter, and with huge amps and volts that converter would be large. Another point of limiting factor is charger cable, which can’t be very huge either, otherwise you would need some assistance in connecting it to car.
The reason I would choose capacitors at the charge site is due to there quick charge/ discharge time and their operational life. From what I have read LI ion batteries have a life span of 5 years or so; capacitors have a life span of 15 years. This will allow stations to have a longer life of service between replacement time. With a three times the life span this would cover the slightly higher cost of capacitors. The cable size would roughly be 1.5 inches in diameter to handle a 200 amp @ 1700 V this would charge the a 85 Kw vehicle in about 15 min. As for safety the typical driver would not perform this task. Workers at the station would be need and would ask the driver and passengers to wait in the store front of the station until there number is called or name or what ever system the station would use. So for drivers in New Jersey nothing would change since all the gas stations are still full service. Second layer of safety would be the charger it self . The Charger and the car would talk and confirm a safe connection and the line is clear for power to be transmitted. If at any point the processes would become unsafe then the charger would stop power. Hmm I think i just described the recharge safety already built in the all Tesla models and add an extra layer to the high voltage charging unit. As for the car side of the high power charge the power systems designers could look in the a second recharge power loop to handle high power recharge applications. Remember if you have battery to battery charging one battery needs to be charged which means the once the station has used all of it batteries for charging it will close for the day limiting the number of cars that can be charged. While the capacitors banks could be charged in a matter of 30 after recharging a car and would only need close for regular business hours. the other problem with battery to battery is that order to completely fill an empty battery you need the charger battery to be twice the capacitance of the empty. Capacitor technology is moving ahead faster than battery tech and should be looked at for recharge stations.
Any way we find to provide a infrastructure to support EV transportation would be a step in the right direction. Remember that when the model T debuted in 1908 you only could by gas at the refinery. in the 20’s and 30’s you could buy it in hardware stores. It wasn’t till the 50’s when you saw gas stations as we know them today and that infrastructure wasn’t complete till the 60’s.
You could make the car have a 2000 mile range and people will still complain that they cant charge when they want to quickly.
The simplest form of storing energy is in a gyro. 300lbs wheel at 300,000 rpm. We need autonomous cars, a cheap computer posted every 1 mile that has grid cordinance, road conditions, ubstructions, gps, etc transmitted to the cars. No more accidents, 150 miles an hour, no insurance, no traffic lights, no age limit, no vehicle size requirment. Tesla would have energized the cars with these.
Daimler has acquired 10% of Tesla as everybody should now know. In press release Tesla (Elon Musk) says that it is mainly interested about Daimler battery tech. Does anybody know what tech that is? Best I could find was this: www.zsw-bw.de/info/current/365Orte/Barenschee.pdf
That shows that they have 200Wh/kg battery that has excellent cycling capability (over 2000 cycles with 90% capacity which equals about 400000 miles running in Roadster). Energy density isn’t that high. 200Wh/kg is not anything extraordinary. With Roadster 450kg battery pack, assuming 100kg casing, that would be 350kg*200Wh/kg = 70kWh battery pack. That is only 23% improvement. Of course that battery seems to be rather durable so it might not need as heavy casing and complex environment control system. If I drop 50kg out of that equation I get 80kWh which is about 33% increase. 240 * 1.33 =~ 320 miles.
I do expect at least 400Wh/kg batteries appearing in the market in next two years. When Type S is ready it should have 600 mile range, not 300.
It might be that main benefit from this co-operation is that Tesla is getting those batteries in discount prices.
Joshua Maxwell; I would use flywheels for high life span. They have relatively high energy density, are relatively cheap, easy to maintain, and have no capacity degradation over time.
Capacitor tech is not moving faster ahead than battery tech. Batteries in very close future should give about 1.5-2kWh/kg energy density and power density of over 100kW/kg, maybe over 200kW/kg. That is capacitor-class power density with battery energy density. No capacitor can match that. But that doesn’t matter in this case.
You say that you can charge capacitor in 30 (what? minutes I assume). You can do that same for batteries or flywheels. That’s no problem. Speed of recharging is not battery/flywheel problem, it is grid connection problem. You gain no advantage of capacitor fast recharge capability when grid can’t deliver you that power. For price of one supercapacitor you get 10-100 or more high enough energy density batteries / flywheels, so capacity timeout is not battery/flywheel problem, it is capacitor problem. Note that you don’t need to use high-price, high energy density lithium-ion batteries, you can use whatever is cheapest in long term. Recharge station doesn’t have space- or weight-problem like cars do.
In all cases, no matter which tech you use, you need grid connection that can deliver enough power to charge all used batteries/flywheels/capacitors in a day. That means for 24 85kWh cars 85kW connection, which is way beyond ordinary grid connection. For more more. Luckily with high capacity car batteries charging stations don’t get many customers during one day that charge their cars. You need to use charging station _only_ in long road trips. That should reduce customer base in about 90% of current gas station customers. That also means that charging stations wont generate income unless they deliver some other service like restaurant.
As for completely filling battery from another battery, you don’t need twice the capacitance. Voltage used determines which way current is flowing, so you can drain one battery dry while other is recharging until voltage drops below charging. This same obviously applies to capacitors too.
That 200A @1700V is for volts too high for car to handle. Best voltage for car would be its battery pack native voltage + some for charging so that onboard PEM can handle that voltage. That means 200A @ 500V or so. That is 100kW which would charge 85kWh battery in about 50 minutes. That’s fast enough.
I don’t believe that people would complain about “slow charging” with 2000 mile range. With that kind of range they wouldn’t even notice that it takes time to recharge car (or at least 99% of people wouldn’t). Electricity is available pretty much everywhere, and if you have that kind of range you just plug it in when you are home and leave your garage every single day with full battery pack. 2000 miles at 60 mph would mean 33 hours of driving without chance to charge even slowly. That is more than two days of 16 hour driving if you sleep 8 hours in between, _and_ you don’t charge your car (even slowly) at night. You would need roughly 240kWh for 8 hours = 30kW connection to charge it back full during night. Half that (15kW = 380V @ 40A: no problem for charging) and you can drive nearly four days with no need to fast charge your car. Initial car range makes a big difference.
I think the battery tech that Daimler has that Tesla whats to test is the new SCib battery from Toshiba I read in an article a week ago that I cant find now that Toshiba had given some of these batteries to major car makers in the US and Europe to test for use in EVs.
www.autobloggreen.com/2007/12/11/toshibas-new-scib-battery-charges-in-5-minutes-releases-march/
Timo and Michael you mentioned gyros for the charging station I don’t see who they would work efficiently for electrical power transfer or storage. You would waste a lot of energy going from electrical to mechanical and then back to electrical to charge the car. Batteries would also have a similar loss due to their internal resistance. Capacitors do not have internal resistance and are there for more efficient. The way the charge stations would be profitable would be from as you said a restaurant , food mart, Arcade, or some other store front, or mechanics shop. They could also make money by providing power back to the grid when not charging cars. Three of these capacitors per charge bay would be enough to charge a car www.maxwell.com/ultracapacitors/products/modules/bmod0063-125v.asp. Though I share my name with the company I am not affiliated with them in any way its just a happy coincidence.
I found the article that states that Toshiba has shipped the SCib’s to leading car makers.
www.reuters.com/article/GCA-GreenBusiness/idUSTRE53C4MR20090413
They look vary promising
All this talk about charge stations needing to store power is just not reasonable. Electric power companies provide 3phase 480V power to millions of factories world wide and can easily do the same for charge stations. At the last company I worked at they made school buses and factory was about 80,000 sq.ft. (small by most factory standards). It had a 600 amp service. This power supply is 480 x 600 x 1.73 = 498kW.
Evonic (Daimler) batteries are far superior to Toshiba’s scib. Evonic are Lithium Manganese Polymer as are Chevy Volts, Tata’s Indica EV, Kia, Hyundai. Toshiba may be trying to flog these batteries to auto companies but no one is buying because they are much lower energy density.
I just read (again) Sciencedirect Journal Of Power Sources. There has been change in articles compared to last year. Now it is not even a news to have 500Wh/kg energy density, in fact all tests are made for those chemistries that provide *at least* that high energy density.
Higher energy densities are now in class 200-300mAh/g with around 3.5V (translates to 700-1050Wh/kg) and even those are not “big news” just ordinary experiments. Biggest I saw was over 2000Wh/kg.
Those are so called gravimetric energy densities. Volumetric are normally about twice as high, so 2kWh/l or 200kWh for 100 liters which would give you range over 600miles (about 705miles with Type S efficiency) and is about size of large gas tank. That would weight about 200kg. Considering that 185kW electric engine weights a lot less than 185kW ICE engine + heavier transmission + other accessories that ICE needs weight/power -ratio is then in BEV favor. ICE range is still bigger, but about 700 miles is over breakpoint (10 hours of driving at 60mph average speed), which means that you need to rarely recharge even in longer road trips and when you do you can choose which “recharge station” you would like to use to get where you are going and are not forced to use always same one (these recharge stations obviously don’t exist yet).
Joshua Maxwell; Flywheels have very high efficiency: about 95-98% (basically electric engine/generator efficiency). Also batteries have that same high efficiency. You do have losses, but they are not big ones. Flywheels do not have any capacity degradation over time, are relatively cheap / Wh and very easy to maintain which is their main benefit over pretty much any other energy storage method. Main point is that they are cheap over time.
Also: read that Maxwell ultracapacitor data sheet. Energy capability of one of those is 101.7Wh. That means you need about 850 of those to get one Type S 85kWh 300 mile battery charged. Not three. One unit weights about 60kg. That is 60kg *850=51000kg. One unit has dimensions of 762 x 425 x 265 mm (~0.085 m^3) so 850 of those is about 73 m^3 or about 2m*6m*6*m. That is for one car. And that doesn’t count necessary air caps between units.
I don’t think Daimler or Tesla would be using SCiB batteries. They have lousy energy density of about 67Wh/kg which is little bit over half of what Tesla is using now. Only good thing in those is that they can be charged fast, but because charging speed is really limited by connection that doesn’t matter.
Joshua Maxwell; I found online store for those Maxwell ultracapasitors. One with slightly higher energy density (BMOD0058 E015 B1) has energy density of 2.67Wh/kg and weight 680g. That has price of $247 / unit.
To get one 85kWh battery charged you need 85000Wh/2.67Wh/kg = 31835kg of those. Since one weights 680g that is 31835000g/680g = 46816 units. Times cost = $11 563 670. That is a lot of batteries or flywheels.
If those get price a lot down or energy density a lot up then I agree with you, but as it is now capacitors just aren’t useful.
For flywheels I found several articles, example this one: www.itpower.co.uk/investire/pdfs/flywheelrep.pdf
That shows that flywheels aren’t exactly cheap either (initial cost around $1000/kWh) but their maintenance costs are very low and usable lifetime decades long.
It might be that standard “cheapest battery you can find” solution would be better than flywheels, at least for now. For $85 000 you can buy huge of battery-based storage unit. Maybe litium-ion batteries win this race too.
Lihium shortage? Is it possible?
I think it is. Current estimates of easily accessible lithium is between 8-20 million tons. Lets get optimistic and say 15 billion kg would be what we have. There will be about one billion cars out there soon (China and India are fast growing in this). One billion cars with 200kg battery packs is 200 billion kg. Even if we assume that only one tenth of that is lithium it is still 20 billion kg. Even if we recycle every bit of lithium it might not be enough.
It might be that lithium ion -based batteries are not “savior of the future” after all. We might need some other method of storing energy if we want to use EV:s. Fuel cell cars maybe if non-polluting cheap method of generating hydrogen is invented, or ultracapacitors if they ever get near batteries in capacity. Superconducting magnetic storage? Maybe in distant future with high temperature superconductors. Nuclear fusion? Not entirely impossible if something like Focus Fusion concept can be miniaturized in car-size energy source.
Aluminum as replacement for Lithium? That could solve pretty much all problems for abundance, but I haven’t seen realistic aluminum battery concept. Europositron claims that they have invented one, but that is very likely to be just a scam to collect money.
Anyone seen any feasible battery concept that isn’t based on lithium? It would need to have at least 400Wh/kg potential to be realistic replacement.
Timo, a feasible replacement for the batteries will hopefully be future ultracapacitors… forget the batteries all together.
With almost instant recharging you should be able to recoup a significant amount of spent energy through the dynamic braking system, they have a longer life than any current battery and they’re more efficient. There is a lot of potential in the ultracaps (or superconductors), and they’re already being used in mass-transit applications but until the technology is refined and filters down to the automotive level it seems most companies pursuing the battery technology are placing their bets on lithium.
Christopher Kiely; We have to use batteries for now. There just isn’t any other feasible alternative. In future there might be, but as you can see from my post to Joshua Maxwell current ultracaps have two-three orders of magnitude too weak energy density, and there is nothing in sight to show that they get much better than that. In fact I don’t believe they ever will get close to even NiMH batteries. In automotive use higher efficiency is nullified by increased weight. One good thing is that they really can be used to collect nearly all braking energy, but OTOH so can best batteries too.
Don’t get me wrong, I do hope that something like EEStor system could be viable, but as it is now they lack necessary energy density to be useful. *IF* EEStor is real then we might have alternative very soon, but I’m pretty sceptical about that.
I read that MIT is looking at nanotubes applications for ultracapacitors. They feel that coating the ion collecting area with nanotubes can increase the surface area by 5 to one. The nanotube coating also allows twice the voltage over current technology. The combination is projected to increase the energy density of ultracapacitors from 5 % of battery technology to 50%. They also spoke of being able to extract more of the energy from capacitors in hybrid cars than from batteries. I question this since the more charge that is depleted from a capacitor the lower the voltage becomes making its use limited.
www.popularmechanics.com/science/research/4252623.html
Tesla Power System Conversion for 1960 MGA
I have a 1960 MGA that is begging for an electric conversion.
How does one convince Tesla to sell its power train/control system to Antique Car Hobbiests??????
Rich Colwell,
One of the frustrating things is reading about all these great new developments, and finding out that non are actually available to individual users. Tesla does make the best motor in my opinion, but there are several that come close including Raser (licensed to Hyundai), Kaisei and tm4 (only prototypes, I think), and PML Flightlink. Only PML has announced that they are making a production line for their Hi-Pa drives and this link www.hipadrive.com/faq.html says about 18 months (been there for almost a year). Now I’m not a big fan of wheel motors, but if you are creative, you might be able to use one in the position where your ICE is, or maybe with the axis vertical and a 90 deg drive.
Good Luck
Just now, I started visiting this blog. What’s striking is your Range Vs. Speed curve, which is equivalent to vehicle efficiency vs. speed. Whether this represents human transportation efficiency (if you consider driving time unproductive) or not, the fact is that drivers actually spend most of their driving miles at low speeds. Think about stop-and-go driving. As an engineer with a transmission (IVT) invention, I’ve studied vehicle kinetics and demographic statistics to get a feel for real-world practical applications of transmissions; this study revealed that American drivers go only 11 m.p.h. on average! This is probably a surprise to most readers here. Now look at the Tesla Roadster ‘Range Vs. Speed’ curve again; maximum efficiency is at ~18 m.p.h., but at American average speed of 11 m.p.h. it’s efficiency is ~94% of maximum! That’s excellent! It is as though the Tesla was intentionally designed for our real world driving. Does this mean we should expect 11 m.p.h. range, on average? No. Our mix of driving speeds includes 65 m.p.h (or more), and one should consider the *distribution* of our speeds. As the CTO explains, such efficiencies fall off drastically at low and high speeds because of nonlinear effects, such as parasitic losses, and high order functions of aerodynamics & tire drag. But in total, high efficiency is obtained optimally here. Drivers have little choice about their driving speeds, so this efficiency is fortuitous. American driving speeds are likely representative of world-wide driving, approximately. Tesla is doing what other auto engineers should have done long ago. Consider reality!
Barry A. Simkins; I agree that Tesla is tailor-made for average US citizen, but I don’t think that low speed estimate applies to all of us. US is notorious about that there people use cars to get everywhere, even very short distances. That is not true all over the world. 11mph average speed is obviously artifact of sitting in traffic jam most of the time and driving very low speeds at city centrals.
I myself live in about 1M people city and not all of us own a car because we simply don’t need one. There are trams, metro, city buses and excellent light traffic ways. In cities with excellent light traffic ways using bicycles gets you in your destination faster than with car. In fact I probably get to work faster *walking* than with a car (about 25 min walking distance) if you count time from door to door. If we want to get somewhere longer you can always rent a car or use a train.
As for me specially I need car only for long-distance driving, and then average speed is closer to 50mph than 40mph.
Then again that might actually mean that global average driving speed is 18mph
I just read an article about a recall on the roadster. It seem that the rear suspension may have had its bolts torqued incorrectly.
www.pcmag.com/article2/0,2817,2347873,00.asp
If any owners could shed some light on this issue it would be help to hear about Tesla’s customer service.
@Timo: Thanks for the informative posts! Did you read this blogpost about the availability of Lithium? gas2.org/2008/10/13/lithium-counterpoint-no-shortage-for-electric-cars/
Sounds like the Silicon shortage for PV: not really a problem. Just an industry taken by surprise. Now new factories actually bring the price down.
I really hope your predictions about 400Wh/kg or more in a couple of years pan out, especially if the price where brought down to 1$/kWh or something. That would really be the end of the internal combustion engine. And good riddance.
Would you be willing to keep me posted on battery developments you read about? Do you have a blog?
hello. what about the safety of these cars? the safety about the electricity and about airbags or the braking system.
Hi great car.
It would be nice to see more details about your drive system on the web. Like S1 and S3 torque-speed characteristics.
Regards
Frank
Auke Hoekstra; Thank you very much about that link. It seems that my info about lithium shortage was simply wrong. I thought that easily accessed lithium reserve is very limited, but if you can get it from seawater with just $30/kg, then we have way more than enough lithium for those batteries.
Also that you need only 1.5kg of lithium for 1kWh battery that means that it costs $45 to get 1kWh battery. Lithium battery price comes from something else than materials.
So, lets get those 2kWh/kg batteries at $1000. 500Wh/kg very near future and more shortly after
(I assume you did mean to write about lithium, not silicon. Silicon is, if I recall correclty, second most abundant mineral in earth crust. Ordinary sand is mostly silicon).
No I don’t have a blog. I work at university so I have access to all kinds of scientific materials that you usually would need to buy for free, and I’m just read a lot of those.
Dimitris; Tesla ESS is very safe, and designed to disengage in case of accidents. Cars are also otherwise safe too, there has been real life accidents already with Roadster and those have shown that they are safe cars to drive.
Tesla ESS is a lot safer than gasoline, except maybe in case where you drive your car into lake. In that case I really don’t know what happens.
Brakes are just ordinary friction brakes, so no difference there. Regenerative “braking” is actually engine brake, and engages when you lift your feet from accelerator, not when you press the brakes.
Hi Timo, I think it may be a race. Can battery technology improve to the point where batteries can be quickly charged through the dynamic braking system? Or can ultracaps (supercaps) meet the energy density requirements first?
Both technologies have desirable and undesirable characteristics. The ideal energy source would contain characteristics of both batteries and caps: energy density of a battery, life span of a capacitor, ability to be repeatedly and quickly charged like a capacitor. It will be interesting to see what technology wins out. I am also skeptical about some of the “on the horizon” technologies that seem to get announced weekly these days, but I temper my skepticism with a heavy dose of optimism about the future of EVs.
What is important is that consumer products like the Tesla are successful, because consumer demand is what’s going to drive the R&D.
Here’s an interesting article on “nanoball” batteries that are attempting to combine the quick charging benefits of a cap in to a battery.
www.newscientist.com/article/mg20126994.700-nanoball-batteries-could-recharge-car-in-minutes.html
Timo: Let’s see; you are interested in Tesla (Menlo Park), and you live in a city with 1M. San Jose? Academic. E.E. or M.E. student or prof? SJSU? Whatever. I used to bicycle to work in Silicon Valley, about 13 miles each way, and would pass my car-driving coworkers several times during the trips. City driving is slow. You are painfully right in suggesting that many Americans use cars for short distances, where infrastructure like Caltrans, BART or bicycles would be more efficient. Cars mean freedom & independence to Americans. This cultural bias must change. Car companies have historically responded with accomodation, not leadership; this is the moral equivalent of a drug dealer dispensing heroin. We haven’t embraced our light-rail commuting in droves. American drivers prefer to lug around thousands of pounds for the convenience, privacy & security of driving. Tesla’s challenge is to persuasively nudge those habits into more efficient modes for us. A Roadster that can go 0-60 in 4 seconds and125 mph tops is only a marketing tool to dramatically introduce us to a solution.
The goal of electric cars should be to produce vehicles that are light and efficient enough for city driving *and* long, fast trips. Few car buyers will want two specialty cars, each. We should be persuaded that compact cockpit volume, light weight and some discomfort are attendent to more necessary economy. This will require imaginative car designs that significantly reduce aerodynamic drag, and provide sufficient performance & best economy at low & high speed. If Tesla does this progressively, Americans will adapt by buying their cars.
Electric vehicles would fit very naturally into a digital public personal transit service; digital control of a fleet of computerized cars that go to your home and take you where you want to go, then head off for the next passenger. etc.
Great post! This is an excellent read and a great website. Thanks for the information.
Here is an interesting article exploring the use of breathing lithium ion batteries which claims a potential of 10 times the energy density of current lithium ion batteries. It is similar in concept to the zinc-air batteries currently used in hearing aids. It replaces the dense lithium cobalt oxide anode with a lightweight porous carbon material. The battery absorbs and release oxygen from the air during the discharge and charging process.
www.newscientist.com/article/dn17159-breathing-batteries-could-store-10-times-the-energy.html
It is obvious to most that a generator and the electric motor are basically opposites. If the electric motor is turning a generator then why do you need a lithuim battery? What most don’t know is a lituim battery causes more pollution to the environment then gasoline. Basically what I am saying is why do so many companies try and pretend that they are not intellegent enough to place the battery on a relay and run the motor off an alternate electrical source when the motor is in motion, meanwhile charging the battery back up like the basic opperation of todays automobile? Don’t get me wrong I really like the Tesla Products but I think it is a bit of a copout to deny people the reality of what transportation should be.
Joe;
With either the air-carbon or nanowire silicon anodes, and perhaps this Lithium-Manganese cathode [ pubs.acs.org/doi/abs/10.1021/nl8024328 ] it will be possible to get a very potent battery indeed! Of course, storing 10X the energy means feeding in 10X the energy, so the demand for hi-power charging facilities would mushroom.
Now i was just wondering. It says here that the Tesla will reach a top speed of 125 mph. Is there anyway that you can make it go faster than that. i was told a while back there is a way and that they do go faster than 125 mph.
Answer back
Brian H:
With the increase in battery energy density from nanowire or air-carbon (or other technologies) allows one to use smaller lighter possibly cheaper batteries to get 300miles or even 600 miles per charge. The fact remains that the average driving distance is about 40 miles per day and having more range will not put a bigger burden on the power grid. The longer range battery is a convenience for the occasional vacation trip or other long trip need.
RomanKorvinus; You said:
“It is obvious to most that a generator and the electric motor are basically opposites. If the electric motor is turning a generator then why do you need a lithuim battery?”
What would you benefit from that? You need energy storage in some form, energy is not free. That’s why lithium battery.
“What most don’t know is a lituim battery causes more pollution to the environment then gasoline.”
That is just not true. Care to explain why do you believe so?
Does Tesla Motors really do all these engineering measurements and calculations in imperial units? Or do you work in SI and convert to imperial for the publications and web pages?
PS: Are the nuts and bolts on the cars imperial or metric?
Roman is clearly deeply confoozed.
The batteries are almost entirely recyclable, and the power they store is generated far more cleanly and efficiently than gasoline can achieve.
So he’s blowing smoke thru his hat out his posterior orifice.
@Timo: yes I did mean Lithium. Glad that you found my link useful but be careful because the process to make Lithium from seawater is not proven technology. On the other hand: I read somewhere else (don’t remember where) that we have not really “scourged the earth” for Lithium. It was simply too abundant and cheap until Lithium batteries emerged. This is also a useful recent study into the price of Lithium batteries and their competitiveness when build into ER-EV’s like the Chevy Volt: dukespace.lib.duke.edu/dspace/handle/10161/1007
BTW I am a great fan of ER-EV’s (I like the GM marketing term better than the PHEV) because it’s simply a win-win solution that automatically leads to EV’s once batteries/supercaps can be charged quickly and once the infrastructure is in place.
And by the way: did you see the “Lightning Car” that uses A123 batteries and claims it can recharge for 300km in 10 minutes. Not for sale yet but like the Tesla Roadster it is a very cool car!
Hey guys your cars look awesome! The “S” may just be my next car purchase. I was wondering how is the car heated?
I live in Toronto Canada and a car like this will need to perform well in the cold. How much will the range be reduced with the heater
operating in the winter?
T.
Auke Hoekstra thanks for the input on the “Lighting Car”. It has some interesting design features. It has permanent magnet brushless motors in each wheel. It also plans on using a nano-titanate form of Lithium ion battery. This battery technology has a shorter recharge time, a longer life and increased safety at the expense of some energy density. It is interesting to see all this technology evolving for EVs and its ability to get rid of all the ICE baggage of gearboxes, differentials, drive shafts etc.
Perfection, i think that Nikola Tesla would bee proud that a factory and a car like this has his name. Reading these comments and ideas i got one my one, regarding better consumption of accumulated energy. The prime idea and genius of Tesla`s electromotors is the simplicity, one rotor one stator and miracle, energy, my idea is to make a rotor of almost every moving part on the car ex. tires and transmission that until now had only a passive (spending) role. This is way to create a amount of energy that can bee used for peripherals like stereo, car lights, etc. or maybe even more. Ok this will cost you one Tesla roadster
joke 
maybe 
. Everything best from muther land of Nikola Tesla, good work and good luck.
Auke Hoekstra;
Range extender EV is slightly different than ordinary PHEV. Ordinary PHEV has emotor in parallel of ICE and when you need more power they both are used to transfer energy to tires. RE-EV has them in serial so that all the power to the tires comes from the EV and ICE is used as generator to charge batteries / transfer energy directly to emotor.
So it is not only term-difference, it is also technical difference. I don’t think Chevy Volt will ever be very successful, it is obsolete already. All hybrids pretty much are. Future is large range pure EV with fast chargers distributed here and there for those that need it in long road trips. I don’t believe in battery swapping either, that is just too costly in long term for swap stations.
For Lightning 10minute charging, that is entirely possible if you plug it directly to power station. 300 miles means around 80kWh battery and 10 minutes means 480kW connection. 480V 1000A. Not a everyday connector. In fact there is recent invention that allows charging batteries in few seconds (allowing 175kW/kg power density), fully charged battery in about five seconds. Not hugely useful for automotive use (unless you are building a dragster), but for phones and laptops with low energy batteries, yes.
Timo and Auke Hoekstra:
Actually the Lightning claims are not consistent one article claims a 90mile range on a 10 minute charge see:
www.autoblog.com/2008/07/09/lightning-gt-ev-sports-car-coming-this-month/
Another claims a 250 mile range on a 10 minute charge see:
www.motorauthority.com/700hp-lightning-gt-electric-car-available-for-pre-order.html
Neither is 300 miles per Timo or 300 km per Auke. Lots of numbers!
Aleksndar, generators convert mecanical power into electrical power. Using any rotating part as a generator will produce a drag, proportional to the electrical energy producedm slowing it down. Tesla cars already have a motor that can be reversed to act as a generator, restoring some charge to the batteries, but it slows the car down, as the energy comes from the momentum of the car. That is called “Regenerative braking”.
It really isn’t a good idea to drive around with the brakes on, even if they are regenerative, no matter where they are located.
It really does seem that a lot of people are missing the point.
The entire world is moving towards renewable energy sources. To blame Tesla for the total lack of forethought in the energy program of The USA is foolish. The fact that most of the power in the USA comes from either coal or nuclear technology is insane. Bottom line is that there is no alternative but to move to renewable energy sources. This may be solar, wind or even tidal power stations. It will happen, it’s just a case of when.
As for those of you who are trying to solve the range problem with combustion engine solutions, (one demented soul actually proposed a Subaru engine driving a generator mounted in a trailer, which would drastically reduce the possible range due to increased drag) you are totally missing the point.
THIS IS A ZERO EMISSIONS VEHICLE!!!
A more obvious solution is solar panels on every painted surface.
Of course battery technology is moving forward in leaps and bounds, and this type of vehicle will drive that technology to advance at a much greater rate due to demand and supply.
My only concern is the magnetic fields produced by the motor, and the possible adverse effects on the occupants.
I assume Tesla are aware of such concerns, and are using a frequency that is not detrimental to human health. i.e. 55/60 Hz
Rife technology, and the Bob Beck protocol could be employed to actually cure diseases when driving the vehicle, having a positive effect, and actually curing disease whilst driving.
Please follow this up Tesla, because it would be a huge selling point.
I have also seen types of motor that are nearly 100% efficient using fixed magnets, and even heard some rather out there claims of motors that are up to 400% efficient using fixed magnets that move in and out of shielded positions, greatly increasing efficiency…
Yes I realise that most of you see these as crackpot ideas, but a quick Google search will reveal that a great many people hold this theory in high esteem, and many are trying to market it.
Surely worth at least researching to prove or disprove.
Don’t forget that the claims made by the Tesla Motor company were totally rubbished by much of the scientific community.
I would have loved to see their faces when they realised they were so so wrong.
Well done Tesla!
I am saving for my own Tesla car in 2011, and will mortgage everything just to have one!
Ben Ryan; 400% efficiency is just impossibility, it would make perpetual machine reality. Just ordinary emotor runs about 95+ efficiency, which is about best efficiency percent that humans have ever made in any energy conversions.
About healing diseases using electric fields, those are just placebo-effects, nothing real is happening. Same thing other way around.
BEV is future of the automobiles, about that I agree with you fully. Future is also solar and geothermal and other non-polluting energy sources.
Have you given any thought to adding an alternator to the design? That way, you will never have to stop for a recharge, and you can use a smaller capacity battery.
BShumberger;
If I understand you correctly you are proposing generator (alternator) in the car. That is basically range extender that is in some car designs like Volt.
Basic reasons are:
1) They are dead weight reducing performance.
2) They are complex, easy to break machines which creates maintenance costs
3) They increase complexity of the design which increases cost of the manufacturing
4) They pollute
5) They need refilling in gas-stations
6) They greatly reduce pure electric range
7) They are noisy
8) They are dirty
9) They smell bad
10) I just don’t like them
If you consider that this is a transformation from a 36 volt forklift to a 240 volt roadracer, you might begin to understand that this technology has been around for many decades. You must , also, stop to concider that there may be something else that you missed. I am not talking about regenerative braking, or using a motor as an alternator when you apply the brakes. I am talking about adding a dedicated alternator. And, before you condem me, you should really take a closer look at the schematic, to see how it would fit in.
BS;
You clearly have no clue about what an alternator is. In an ICE car, it takes energy from the motor and turns it into electricity. Since there is no gasoline motor in the Tesla to drive the alternator, you’ll have to rely on hamsters in rotation cages. LOTS of hamsters. LOTS of cages. And no, you can’t use the battery to drive the alternator to charge the battery. Why? God says so. (He wrote the Laws of Thermodynamics specifically to frustrate fools. Sorry!)
Tesla has done a great job in demonstrating what an all Electric Vehicle (EV) can be. However the all Electric Vehicle at this time in history seems to cater to a niche market. There are few if any charging stations and no effort in progress to install them. Owners of EVs would have to limit their trips to 200 to 300 miles round trip so they can recharge at home. I call this an “absolute range limitation”. Such owners would have to own or rent an additional internal combustion vehicle to accommodate longer trips.
The REEV (range extended Electric Vehicle) like the Volt and the PML mini www.treehugger.com/files/2006/08/the_hybrid_mini.php offer a viable alternative to the EV for reducing dependence on foreign oil without the “absolute range limitations”. One could buy such a vehicle and use it for both everyday commutes as well as longer trips, since there is presently a network of petroleum fueling station across the country. These vehicles run on all electric till the batteries run low and then switch in an ICE motor generator to provide electrical energy to drive the motors or recharge the battery. This motor generator is the size of a spare tire in the PML mini’s case. The advantage of this serial concept over the ICE direct drive parallel concept is the elimination of gearboxes and dual drive mechanisms. They allow the vehicle to maintain the clean architecture of an electronically controlled electric motor power train. The ICE motor can also run at a single rpm for optimum performance while generating electricity. While running off the ICE regenerative breaking could still be active to provide additional battery charging
The main advantage of the REEV vehicle is that even with a reduced all electric range (from smaller battery) they would provide a big if not total reduction on our dependence on foreign oil. Since the average commuter distance is about 40 miles the REEV could on average get almost all of it energy from the power grid. Since the power grid derives only 1% of its power from petroleum products the REEV greatly reduces consumption of petroleum products. The major power grid fuel comes from: 49% coal, 20% natural gas and 19% nuclear, 7% hydro and 3 % from wind/solar (solar being the smaller). Right now our automobile fleet is a major consumer of petroleum in the form of gasoline and diesel fuel. We do use petroleum for other products such as plastics etc. By reducing our usage of petroleum to 40% of our current use allows us to only use our domestic petroleum production eliminating oil imports.
I know you EV purest feel this is heresy. But it is better to refill at a gas station rather than call a tow truck. The range extender weight is offset by reducing the battery to better optimize it for the average commute distance. The range extender is dead weigh just like the extra battery capacity is dead weigh when not used for the average commute distance. The ICE is pretty reliable these days and would only get used for long trips. They pollute only on those rare long trips. It is an interim crutch till charging station catch on.
We may not be able to count on GM to develop it Volt due to its financial situations. Tesla would have a good size market if it used its technology to develop such a product.
A gasoline engine drives the alternator through the use of a belt. You can do the same thing with the drive motor.
Something too simple for intellectuals to understand?
BShumberger, an alternator is just a device to turn mechanical energy into electrical energy. So, where does that mechanical energy come from? In most other cars, it comes from the gasoline engine, but an electric car has no gasoline engine. The only source of mechanical energy in the Tesla Roadster comes from the movement of the car itself, tapping that would slow the car down - and that is precisely what the regenerative braking is. When it needs to slow down, it transforms the motor into an alternator, slowing the car and partially recharging the batteries.
Now, I suppose you could put bicycle pedals on the passenger side, connected to an alternator, but with the limits of human power, that would mean an awful lot of exercise for very little distance!
By the way, I am glad you inquired about the schematic that I was refering to. Oops, I forgot that nobody seems to have the necessary curiosity to ask the right questions.
I have tried to present a solution that I beleive will dramatically increase the range of an electric vehicle. I have been met with self- righteous, more holy than thow responces. Am I now to receive the silent treatment? Or, is there any one there who wish to duscuss my solution in a more mature, professional, and respectfull atmosphere?
For all the would be engineers out there who devise ways to recharge batteries while in transit. The mean must follow these rules:
1. Energy flows from high potential source to low potential sink. ( ie Positive terminal to ground)
2. There is always energy loss due to heat. ( yes even in wires they have resistance )
3. the source and sink must be out side the object doing work. ( ie the battery is independent from the motor)
With these rules you can not charge the battery and run the motor from the battery concurrently you do one or the other.
BShumberger; there is nothing to discuss. Alternator connected to emotor is just brake connected to motor. Alternator collects its energy by slowing down whatever it is connected to, so basically you are proposing to drive with brakes on, which is always bad idea. Your idea is not a new one, this is proposed every now and then. Energy is not free, not magnetic, not electric and not kinetic. Alternator you are proposing just turns kinetic energy to electric energy (with losses) , which is exact opposite what emotor is doing. You just end up losing energy, that’s all.
Many scientific and engineering concepts like balance and equilibrium have been known by man for hundreds, if not thousands, of years. Circular motion has been understood since the invention of the wheel. Variable frequency has been understood at least since the invention of the vacuum tube. Two wheels and a rope can be used to make a “Block and Tackle” to lift objects that are too heavy for us to lift by ourselves. A lever and fulcrum become a seesaw at a children’s playground. All of our current technology has been constructed from simple concepts that we now take for granted. Only a nefarious, modern day, pirate could create the label of THERMO-DYNAMICS, and then claim that nobody can understand the principles of YIN and YANG as well as he does.
There are companies that have been using power inverters and variable frequency drives to control traction motors in electric forklifts since the 1970’s, or earlier. Instead of the automotive companies acknowledging that they are catching up to 40 or 50 year old technology, these intellectual neophytes are trying to convince us that they are creating this technology for the first time, and that it has been a very difficult undertaking.
I have found a solution that is “hidden in plain sight” within the automotive electrical system. This solution will allow a person to drive an electric vehicle across the nation without having to stop and recharge the battery pack or switch over to a gas powered generator. This solution also makes it possible to build a generator system for your home that will completely eliminate your monthly electric bill. A small, 5 volt, portable generator system can be built for use with your cell phone. If you are honestly searching for an alternative energy source, there are many more possible applications to consider, even in the aerospace industries.
If your engineers and technicians can not figure out how to accomplish this from the concept that I have presented in my previous posts, I would be more than willing to demonstrate this solution in person, for a price. Of course, you could always practice the teachings of Toyota, and Gemba Research, and steal the ideas from your sources, and demonstrate a fundament lack of respect for the principle of diversity. While you’re at it, make sure to erase all of these posts before anybody else can read them, and commit an act of piracy against you. (Edison vs. Tesla all over again?)
I am not the one putting a government grant, or future sales, at risk. Also, understand that this system can replace a $12 billion nuclear reactor. Make your choice. Make an offer. Otherwise, I’ve got no future, and I’ve got nothing to loose. Do you?
P.S. There is no room for sarcastic adlibs, and commentary, in any serious negotiation or decision making process. Wouldn’t you agree?
BShumberger, What schematic? Where?
BShumberger, our attention was elsewhere, we were not deliberately ignoring you, and we don’t mean any disrespect. So, if I understand you correctly, your proposal is to use the drive motor to spin the alternator, which in turn would provide the electrical power for the motor? That is a very old idea, darn near every schoolboy thinks of that when they first learn of motors and generators.
Problem is, it takes some mechanical effort to produce electricity and the amount of mechanical effort needed is directly proportional to the electrical power produced. Try one of those hand cranked flashlights some time, and you’ll see what I mean. If an alternator was connected to the driveshaft, the drive motor would have to work harder to mechanically power the alternator and the motor would require more electrical power, thus draining the batteries faster. Now, if both motor and alternator were perfect and 100% efficient, that alternator would produce exactly the same amount of extra power the motor needed, there would be no gain and no benefit at all! But it is worse than that, no motor or alternator is perfect, there is always some friction and electrical resistance wasting a small amount of power as heat. The result is, adding an alternator the way you propose would actually waste power and energy, reducing driving range and performance. Not a good idea, I’m afraid.
There can be improvement at many points in the charts. For example the charts show it is possible to gain efficiency at every point on the chart and the battery would only be needed during acceleration times. Efficiency could extend the batteries effectiveness during all other times extending the range of the battery and car to a few thousand miles per charge. For simple example during ’stop start driving’ there could be secondary charge systems as in super capacitors that recharge in 9 seconds and can recharge millions of times, and these capacitors could play a dual role of being recharged by regenerative braking and actually driving the car in stop start traffic and traffic jams. These ultracapacitors would recharge a secondary offline battery system of perhaps lithium polymer batteries as well as driving the car. Lithium polymer can be shaped into any shape as it is a plastic. Like cup holders in the car or the passenger seats could be the lithium polymer batteries. Solar cells on the roof could also be continually charging these offline batteries which would be brought online when there is a need of driving range extension. With online and offline batteries and multiple recharging technologies and computer controlled continuous recharge technology the electric car coold go 10,000 miles at 80 miles an hour without stopping. You just have to use your brain a bit and get your brain off off hydrocarbons (gasoline).
Ken, 10000 miles without stopping at 80mph is just impossibility. Supercapasitors you suggest have very poor energy density, so they are poor solution to capture energy, also practical shape car uses about 10-15kW power at 60mph just to fight air resistance, at 80mph that is much worse. That one is power used that just can’t be removed by improving efficiency. Efficiency can’t go over 100%, and Roadster already is about as close to 100% as you can get. You always lose some power to air and rolling resistances as well as ancillary systems.
Only way to extend range over battery capacity is to bring energy to car from outside of the car using something like solar panels. However solar panels are quite poor source to energy: roof covered with one would give something like 100-400W power, which is about 1-2% range extension and they are expensive. You gain more with just watching your power usage “driving easy”. There are other ways like inductive coils into road and that sort of things, but they just are too expensive and can’t be used everywhere.
Of course you could get huge range with huge battery, but that would also give you huge price-tag. In near future you can get batteries that give 1000 mile range with reasonable price, but not quite yet.
very well, you win. I will not bother you wiyh this , again. But, I will continue to work in this direction on my own, because I am not convinced that it will not work.
1. First law of thermodynamics
Energy can neither be created nor destroyed. It can only change forms.
In any process, the total energy of the universe remains the same.
2.Second law of thermodynamics
The entropy of an isolated system not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium.A way of thinking about the second law for non-scientists is to consider entropy as a measure of disorder. So, for example, a broken cup has less order (more entropy) than an intact one, and it is more difficult to repair a broken cup (reducing its entropy) than to break an intact one (increasing its entropy). Likewise, solid crystals, the most organized form of matter, have very low entropy values; and gases, which are very disorganized, have high entropy values.
In all mechanical systems there is friction which converts mechanical energy into heat.
1,2 Law copied from Wikipedia
The key is as you say of ultra capacitors having low density. There are research labs working on this for quite a while whith the low density ultracapacitors being recharged very quickly because of low density and then using these capacitors to recharge high density lithium batteries for example. This is actually the key. So this is being done. Vast amounts of energy can be moved using these ultra capacitors or even trickle charges. This is being done and is well known in the research community. If you are tripping over the 10,000 mile number then try for a lower number. When IBM first heard about notebook thin computers they did not believe it. IBM thought there would only be 100 or so mainframe computers in the world total. They needed to think some more.
Ken, ultracaps are more useful than ordinary regenerative braking only at emergency braking-fast energy gains. Tesla Roadster engine can convert energy at about 200kW power, which, if utilized fully, would cause wheels to lose grip. Just ordinary regen braking is quite enough. You could gain slightly more by adding hub-motors to front wheels too, but not much more. Ultracaps are heavy, so if you use them to capture energy you might actually lose range because of increased rolling resistance.
Problem with range is not efficiency (if you look at the top of this page, only drivetrain losses are something that can get significantly smaller). Problem is energy storage. That storage needs to be high energy density batteries, otherwise you just don’t have enough energy to get anywhere.
Range comes from energy storage capacity / energy losses at certain speed. Even if we eliminate all drivetrain losses you would still have air resistance, rolling and ancillary losses, and with Roadster at 80 mph you would still use about 250Wh/mile which translates to about 220 mile range.
Only practical way to radically increase range is to get higher energy density cheap energy storage system. Efficiency increase is, of course, welcome, but it just wouldn’t increase range much because current systems are already quite energy efficient.
Since batteries do not last “forever” and have their cycle of charges, how much could cost their replacement for new ones?
To Tesla Engineering and top dogs there:
I contacted Fortum (Finnish/Swedish energy company) in order to question if there are any of the charging points they are building between my home and my parents home and what voltages and amps they use. Answer was that they are currently using 1~ phase (230V /16A) ja 3~ phase (400V / 16A) and there is not any yet, but they also informed me that, and now the important point:
There is Europe-wide standardisation for those going on, and they think that they get it done by the end of the year.
They are also investigating techs that allow very rapid charging (10 min charging was mentioned, but not how big battery pack could be recharged that fast). No specifics were told.
In case you are not aware of this development I think you should contact Fortum (www.fortum.com). This could affect your Europe sales quite a bit. You should definitely have compatible system with them for Europe models.
Jaoa;
Presently replacement battery pricing is part of the purchase contract, if desired, at $12,000. It would cost $30,000 purchased new now. The replacement period is 7 years. By then, battery tech may have changed significantly, though.
Random edit notes:
Main text: “just the opposite it true!” –> “just the opposite is true!”
Timo: “hydrogen molecyle is basically just two protons surrounded by two electrons, ” No, that’s helium. Hyrdrogen is half the size. And “molecycle” –> “molecule”. But I do wonder what it would be like to ride around on a molycycle!
Anatoly; it’s spelled “efficiency”. No esses in the word, please! About battery cost: at $12,000 per 100,000 mile pack, that’s $0.12/mile, which is indeed quite a bit. Costs will have to drop. Of course, perhaps that comparison should be made against the cost of maintenance and depreciation for an ICE car for 100,000 miles.
Timo again: battery “form factors” are much more easily matched than internal design. Better Place ( www.wired.com/autopia/2009/05/better-place/ ) now claims its swap stations are versatile enough to cope with a number of types. (40 seconds fastest so far, btw.) Ultimately, ownership of the batteries would be part of the dealer/recharge system, so that the car owner would not care so much about the condition of the new pack he was getting each swap, as long as it had enough charge to get where he needs to go.
Daniel: aero drag; maybe car skins should take a page from the new swim suits that use fine grooves the length of the body (”shark skin”).
Rachel; Detroit auto workers have been rooned by gen’rashuns of union membership. Minimum work for maximum pay is not compatible with the mentality of a world-challenging startup.
TJD; about affording one: the $50,000 Model S would lease and run for about the same total cost as a $30,000 ICE car.
Carl; air ram — only suggested about 50 times. Problem: costs more energy to overcome its addition to drag than it can generate. Consult works by Newton for the reasons.
Timo; the Nature article basically says that electric resistance and charge result from movement in a magnetic field, and that a way has been found to translate “spin” motion into EM motion, hence into charge. So storing and draining spin could create an energy-dense battery setup, or sensitive detection devices. I think.
Brian H.
Hydrogen *molecule* is two protons surrounded by two electrons. Helium doesn’t from molecules, it is noble gas and chemically inert, it also contains two neutrons in addition to two protons. Hydrogen *atom* is single proton surrounded by single electron. As a full atom hydrogen and helium are nearly same size, because most of the size comes from electrons that surround that atom. However, hydrogen can lose its single electron quite easily which leaves only proton, and that is then a lot smaller than full atom.
“y” in molecule was just a typo.
Brian H.
You wrote about Anatolys post:
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About battery cost: at $12,000 per 100,000 mile pack, that’s $0.12/mile, which is indeed quite a bit. Costs will have to drop. Of course, perhaps that comparison should be made against the cost of maintenance and depreciation for an ICE car for 100,000 miles.
—–
If we estimate that you go to change oils, spark plugs etc. in every about 5000 miles and average cost of maintenance is about $200 more than BEV you get $4000. If car consumes about 17mpg (BMW 750i, comparable to Model S) you have 5882 gallons used for 100,000 miles and average one gallon costs about $2.7 (which is really cheap compared to our 1.25 euros / liter) you have $15882. Roadster uses about 250Wh/mile so 100,000 miles you have used 25000 kWh. If one kWh costs about 10 cents that is $2500. 15882 - 2500 = 13382.
Combined $17,382. BEV is cheaper, but not that much cheaper. Also paying that $12,000 at any one time is too much for many people. Fortunately battery tech is advancing and it can be assumed that those prices go down quite a bit in near future.
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Better Place ( www.wired.com/autopia/2009/05/better-place/ ) now claims its swap stations are versatile enough to cope with a number of types. (40 seconds fastest so far, btw.)
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That is still double to 20secs that it takes to plug your car in and out of a charger. What happens between those doesn’t count because you use that mostly at home at night and in longer road trips when you are taking a break anyway. In longer road trip it doesn’t matter if it takes 40 seconds or one hour if you use it maybe once a year. Battery swapping just isn’t viable business, there will be too few customers to keep it alive. It might be viable *now* when batteries have still too low energy density to give 600+ mile range with reasonable price. That changes soon: making 180kWh battery pack from that prototype 540Wh/kg battery would weight 333kg which makes it about 100kg smaller than Roadster battery pack (90kWh should give 300 mile range to Type S -size car).
Note to engineers: Think outside the box a little more, this is a cool car but Americans will NOT buy it enmasse. Just will never happen no matter how hard Adolf Obama tries to force it. Make these beautiful cars go further (without charge) and you will have a winner. To do that you all need to think outside the box. Yes we all know that regenerating power from a power source has been a school boy’s fantasy, then again so was this laptop I type from. There are plenty of ways to make that school boy dream work without draining power from source or creating an abundance of heat. Think….. solve.
Go back and read about Tesla and how he thought. You have a great product, make it better and it will sell.
My two cents.
I’m very interested in this style of TRANNSPORTE, and I want to be part of this project, I want to be part of your team. YOU CAN GET TO BE REPRESENTATIVE IN ARGENTINA, IN ANY WAY TO SALUTE YOU, VERY CAREFULLY GABRIEL QUIROGA
CM,
Check this out:
As you read this, think of my transmission concept as the “mechanical” version of a rocket engine.
No matter how fast a rocket is moving the thrust(force applied) to the rocket is the same. The thrust(force applied) to the rocket is independent of the rocket’s speed.
In my transmission concept(AST) the torque(rotational force) applied to the wheels is independent of the wheel’s rotational speed (rpm).
The torque available is the torque applied regardless of the wheel’s rotational speed (rpm). There is no need to run the motor as fast as the wheel as in a direct drive transmission and no gearing up to reach the wheels’ speed. I know it sounds impossible but believe me it can be done.
Contrary to popular belief - It is NOT the “battery storage” that needs to be increased to obtain greater range in “All Electric” vehicles. I know It is logical to think that because electric motors are already 90+% efficient the answer must be to increase the energy source (battery storage) however the engineers are completely ignoring one important part of the whole system and that is the “method” in which the mechanical energy developed be the electric motor(which is very efficient) is “transmitted” to the vehicle. In other words the TRANSMISSION!
Again it is logical for them to think there can be no improvement in that area because directly driven electric motors are very efficient through their entire working range and any tweaking in efficiency can be done by the use of a CVT (Continuously Variable Transmission). This is were they are again mistaken.
There is a far superior method of applying available torque to a system that is rotating at a much higher rpm and I call it an AST (All Speed Transmission). When integrated with an electric motor as one unit I call it an ASTM (All Speed Transmission Motor). The ASTM can apply a low rpm torque to a higher rpm system(wheels) as if it were “standing still”. In other words, regardless of, and independent of, the wheels rotational speed (rpm) as in the “rocket’s thrust” example. This would be like peddling a bicycle at 40 miles per hour and every time you peddle you could apply the same torque that you had in 1st gear (by the way that can and will be done but that’s another application). But can you imagine what that means to a vehicle propulsion system? It would mean much smaller motors could be used and still achieve adequate performance resulting in far greater range on far less battery storage. Still think it’s not possible? Someone once said “Everything is easy, when someone shows you how”. I can show you how.
Believe me this is not a “something for nothing” concept or contraption that contradicts the laws of physics or a “perpetual motion” dream. It is a solid, physically feasible, unique method of applying torque that has never been done before but can accomplish what I have described.
I believe the ASTM propulsion system is the answer to the “All Electric” vehicle’s range problem. There’s no need to spend time that we don’t have on development of better and/or cheaper batteries that aren’t need. All of our American automotive models could be “All Electric” right now with the ASTM propulsion system.
American’s would dominate the world in automotive manufacturing, thousands would go back to work and we would end our oil dependency and over usage. And we would show the world that American Ingenuity is alive and well and always will be.
How much Mony i must pay for a Teslar-Poster. And can you me send posters to Hannover in Germany?
I am the biggest Fan of Teslar in Hannover.
Herzliche Grüße . . . .the Painterman-Claus Heuer
To all “mystical range improvement device” - suggestions:
You can figure out your range simply by measuring losses at any given speed and divide your power supply with that figure. As simple as that. You can read those figures for Roadster from the top of this page.
There are no mystical ways to get energy from nothing, all energies come from some energy source. In BEV it is battery.
Improvements in efficiency are always welcome, but in machine that already has nearly lossless system any improvement in efficiency wont generate much more range. Even if you eliminate *ALL* losses from system itself (impossibility) you would still have aerodynamic and rolling resistances as well as ancillary systems that generate losses. Those alone make it impossible to hugely improve car range without getting better power supply.
Wayne P. Bishop: Your “rocket engine” analogy is flawed. The thrust of a rocket engine is determined by a simple formula, M*V^2, where M is the Mass of the exhaust, V is the exhaust Velocity, and ^2 means the velocity is squared. The speed of the rocket doesn’t affect the thrust, as the exhaust velocity is measured in relation to the rocket itself, not anything outside the rocket. Note that a rocket is a self-contained system, it does not need to “push against” anything outside it, which is why it works fine in the vacuum of space. A car is different, it relys on friction with the road to provide the “thrust”, the slipperiness of the surface makes a big difference, it relys on the road and is not “self-contained”. For the rocket analogy to work, the car “thrust” would have to be independent of the road and determined solely by torque and rotational speed of the wheels, which is obviously not the case, otherwise the speed of the car would have no relation to the rotational speed of the wheels! (well, maybe on a very icy road…)
Power in a mechanically rotating system is determined by the formula T*R, where T is Torque and R is rotational velocity. Any system that increases the RPMs without changing the power must reduce the torque, and vice versa. So, any system with a high torque low RPM input and a high RPM output must also have a low torque output as well. So, your hypothetical “All Speed Transmission” with a high torque low RPM input would have a high RPM low torque output. Sorry, no way around that, it applies to any sort of mechanical, hydraulic, pneumatic or electrical transmission design. You’ve made an extraordinary claim, and I’ll need to see extraordinary proof from you before I’ll believe. If you can prove your impossible claim, you'’ll be a serious contender for a Nobel Prize in physics.
Power consumption of an electric motor is determined by the power output, T*R, not just the torque only. There is no real efficiency advantage to a “high torque low RPM only” design, except perhaps for a fraction less friction, and that advantage would be lost to friction in any variable speed transmission.
Wayne P. Bishop: your idea of constant torque would be useful, except for one small thing: Electric motor torque curve is already flat from 0-several thousand RPM. Your transmission idea would be good for very fast speeds (RPMs) where emotor torque starts to decline, but for Roadster-type torque range it doesn’t matter much.
Also applying constant torque does not mean that you get any further, it only means that force that accelerates tires and fights losses is constant, and you get maxed acceleration which still slows down when aerodynamic drag and rolling resistances start to climb up. Torque alone only tells you how fast car can accelerate, not how far it can go. You still have losses which increase with speed and limited energy supply, which tells how far your car can go.
To engineering:
I’m curious about similar data for Type S. You don’t need to include range, because batteries will develop still, but base losses are my interest.
Type S looks more “slippery” than Roadster, but is also bigger car. From some webpage I got an impression that 300 mile version has 85kWh battery pack. Using data from this page shows that for constant 60mph speed Roadster needs 75kWh pack to get that same range. That means that Type S has about 12-13% bigger losses. Aerodynamic or rolling? Looking more slippery could mean that aerodynamic doesn’t increase as much, but being heavier would mean rolling resistances do increase. That would also mean that there might be some high speed treshold where Type S has actually more range than Roadster (rolling resistances stay relatively constant, while air resistance is exponential). Which speed would that be? 85mph? 125mph? 200mph? speed of sound?
Any improvements in range or speeds or somesuch for 2.0 version of Roadster? At least PEM is smaller (fox news report), which intuitively would mean better efficiency, weight and thus range.
i may know of a way to increase range! the only place i have found capacitors is on www.overstock.com but they are advertised for car stereo equipment. they have built in regulators and most are shaped like a regular car battery. this would be great in combination with a power source like solar since less weight means less power loss. also, how about forward motion or the engine’s rotation rotating a generator head to keep a charge continuously. there are also low light solar panels on the way. even if the capacitors with regulators are not purchased from overstock they could be manufactured since the tech is there.
I have what I believe is a symbiotic add on technology that will help solve one of your most pressing battery engineering needs of substantially increased range.
By adapting your best current vehicles to accept a tracked overhead mobile umbilical power feed cable capable of not only powering your EV, but also charging your batteries while you are attached to this overhead dollie lane built into the national freeway arteries.
Such overhead feed lanes could be built for both passenger vehicles and separate EV semi-trucks like the new ones at Long Beach harbor.
It’s almost as simple as building an upside down elevated Hot Wheels slot car track, then hanging retractable power feeds from them and plugging it into your EV below it. The small overhead dollie would track and pace the EV below, capable of emergency disconnect via signal or tension on the umbilical tether reel above on the dollie.
The best aspect of such a system is the logical expectation that the federal and state highway depts would be obliged to build the umbilical dollie grids into our interstate system, and that your product can adapt to it with minimum modifications to it.
The guys that run the Mammoth Mountain ski resort are interested in building a very basic overhead umbilical dollie run that can power electric mountain bikes going up their ski runs in the summer months.
It can be done quite easily with current technology, becoming a new X-treme game sport that’s all electric.
Any feedback would be greatly appreciated guys!
Best regards,
Jon Mooring
San Diego, CA
Played around a bit with that excel sheet which you can download here. Increased battery to 85kWh and rolling resistance from around 55 to 85Wh/mil to get 300 miles at 60mph. That should be what type S is close about.
I also searched shortest road to my desination which turned out to be 589.4 km or around 370 miles. Using that excel I found out that I need average 46mph speed to get there. Since that was shortest, not fastest route that means speed limits are mainly 62.5 and 50 mph with some pretty slow parts (37.5 mph or slower) here and there. If I drive around 56.2 and 44 mph at those faster sections of those roads and don’t pass ANY cars and generally use regen at every opportunity at slower parts of the road trip I might actually manage to get to my destination with just 300 mile EPA range. Might. There would not be any margin for error.
So close. Please, PLEASE get a slightly bigger battery pack as an option. I want your car. Even 350 mile EPA range would be sufficient. I would just need to drive slowly to get to my destination. I hope battery tech has advanced so that 400 mile range battery is option when your car is available here.
I work along side this company and not but pure professionals! Well built EV’s and incrediblt talented individuals.
-Mo.
Jon Mooring; Your idea for once is doable, though not very practical.
First: Electric cars use quite a bit power going in those roads, so electric current going in those power feed cables would have to be very high and that causes a lot of losses if you are not using also very high voltages, which increases catastrophic accident possibility.
Second: It costs a lot of money to build and maintain such infrastructure.
Third: Cars are not alike. Big truck can be over four meters high, while Tesla Roadster is hardly one meter. That means that Roadster would have to drag at least five meter high tether with it, and in tight situations (emergency brake, passing other car, need to evade something onto road etc.) forces that apply to that tether and connectors would be extreme. And just by inertia and aerodynamic drag it causes it would make driving quite hard which makes it less safe. Think about what happens if that five-meter tether disconnects from Roadster at high speeds. Disconnecting would cause tether to swing. If that was freeway and there was another bigger car next to that Roadster that could cause that tether to hit that car, maybe with catastrophic results.
Easier would be build inductive coils under pavement and get power from there, but that also has problems one and two, and I think problem two is the main concern here. There have been huge amount of scientific research going how to make roads better and traffic more safe, but most of them just aren’t viable because it just costs too much. And many of them are just daydreams of people that don’t drive themselves, making their suggestions those that rip out your freedom of driving.
If you want “ecological” transportation use electric train. I do, but halibut that’s boring.
To JB Straubel or anyone involved with powertrain development at Tesla,
With reference to my comment on July 19, 2009
Thanks Timo and CM for your resent comments concerning my ASTM (All Speed Transmission Motor) concept.
However I’d like to give special thanks to CM for this comment - “You’ve made an extraordinary claim, and I’ll need to see extraordinary proof from you before I’ll believe. If you can prove your impossible claim, you’ll be a serious contender for a Nobel Prize in physics”. ( I’ll remember that when I except the award.) lol But seriously CM you at least showed an open mind enough to say you would like to see proof before you would believe it. I commend you sir. Anyway, the fact is I CAN show(prove) how it is possible to apply a low rpm torque(motor) to a higher rpm system(wheels) with approximately the same torque (some losses due to friction,etc). I know from a power standpoint of T*R it doesn’t make sense or even seem possible but I have figured out a way to do it. And because the ASTM’s low rpm output torque can be applied to the vehicle wheels when at speed(with NO gearing up) you will save the energy that is now needed(wasted) just to get the motor up to the wheel’s speed even before it can begin to apply torque to the moving wheels. Lower rpms not only saves energy, which extends range, but as an added benefit reduces or even eliminates motor “whine”. Runs quiet yet torque is there.
Let me know if Tesla is interested in learning more about the ASTM propulsion technology. Take care all.
Why recharge at all? Why not just design a car so that a depleted battery pack could be swapped out for a fresh battery pack in the same amount of time it takes to fill a car with gas? Instead of or in addition to charging stations, have swap stations where one drives a car into a station similar to an automated car wash. The system positions the car, deploys some mechanical means of removing the depleted battery pack and installing a fresh pack. Then the driver is on their way in a couple of minutes. Depleted battery packs could go to a recharging center powered by solar and/or wind energy. Then, there is no fossil fuel being used at all.
I can see one issue with this being a situation where a battery pack still has some power left but not enough to reach a destination. Then a driver would be swapping out a battery pack that still has some power left and may feel like some of the power they paid for is being wasted. Perhaps a swap station could measure any power left in the existing battery pack and reduce the payment for the fresh battery pack accordingly
I envision the charge for a battery swap being just a few dollars - the $4 the FAQ says is the average cost of the electricity that goes into charging a battery pack plus a profit margin. I would think it would be far less then the cost of filing up a car with gas.
I figure that all necessary lights are already in LED technology. (including the brake-lights, rear lights)
The only lights that would be necessary to have in non-LED are the xenon headlights/bixenon. However, maybe you can
manage somehow to use the high mca LED’s and some focusing method to replace the xenon? That would give you another few miles at nighttime. Just a thought.
Thanks for the feedback Timo.
The overhead umbilical dollie would be powered itself, not pulled along by the EV. The power feed cable coming down off the dollie would retract onto a reel on the dollie in the event of an emergency disconnect, be it tension related or signal related. The dollie would then continue on by itself to the next exit in need of dollies at the next freeway on ramp automatically, leaving you and your EV on battery power to proceed where you will.
I envision each dollie reel having up to 25 feet of power cord on it’s reel. I also envision an electro magnetic coupling system allowing for automatic connect and disconnect to or from the dollie.
The California Air Resources Board has already expressed an interest in checking out the basic subscale system if and when it gets built at Mammoth Mountain for uphill electric powered mountain bike runs on a designated course. I believe CARB’s primary interest in this umbilical dollie system is for powering electric semi-trucks in the two righthand slow lanes on California freeways.
These overhead umbilical dollies can even be designed to change lanes in much the same manner that trains can change tracks.
The potential of this overhaed umbilical system to substantially reduce our dependence on fossil fuels and promote widescale use of EV cars and semi-trucks here in CA deserves serious consideration in my humble opinion Timo.
Thanks again for the kind feedback.
Best regards,
Jon Mooring
Wayne P. Bishop
Your ASTM isn’t just keeping torque it is mystically generating energy from nowhere. Basically you are claiming that you have invented perpetual motion machine. That is why CM said that comment about Nobel Prize.
Think about it: if you can keep torque and increase RPM in same time you are generating more power, which means more energy.
So lets start with lets say 15W electric engine that runs with high torque and low RPM. Here comes your magical transmission and changes that to high RPM without losing torque. Now, attach a normal transmission which increases torque and drops RPM back to what it was by normal gearing and use that to run 20W generator. Now you only need to loop that and you get perpetual machine that gives out 5W power. Repeat as many times as you want.
You can start with hand-cranked 5W motor and end up giving energy to entire world.
Call me sceptic, but I don’t think so.
This Message is for Elon Musk
A recent Article from MIT, If this is true , ( See Link Bellow)
it will change everything with your recharging of your battery packs.
Re-engineered battery material could lead to rapid recharging of many devices.
web.mit.edu/newsoffice/2009/battery-material-0311.html
Mike Kertesz , MSEE
Timo:
Referring to your statement when you said - “Think about it: if you can keep torque and increase RPM in same time you are generating more power, which means more energy.” and that is like getting energy from nothing and I understand that. And I agree with you. However how do you explain this. If you have a wheel with say two small rocket jets located at opposite sides so as when they thrust they put say a 10 ft-lb torque on the wheel. As you said, or know, the rockets will always apply the same thrust(and therefore torque) to the wheel regardless of it’s rpm. It has 10ft-lbs of torque on it at 0 rpms and at 100 rpms and at thousand (1000) rpms right? Then where did all that extra energy come from when it is now at 1000 rpms with the same torque. The rockets are burning(expending) the same amount of fuel every second and thrusting with the same force, and therefore the same torque, as it did at the lower rpms and even at 0 rpms. Where does the extra energy(power) come from due to higher rpms? I am really asking because this has me puzzled and wish somebody could explain it to me. What I’m I missing? help!
Justin Smith: Tesla engineers are aware of capacitors and their limitations. Capacitors are good a providing brief bursts of power, but their energy storage is very limited, far less than any battery. Adding capacitors would add weight without adding much range. A car sized solar panel would produce just enough power to run a cooling fan, not enough power to justify the high cost. If the cost comes down and performance improves, that might change.
The Tesla Roadster already has a way of converting forward motion into electricity by converting the drive motor into an alternator. It’s called “regenerative braking” and is used every time the car needs to slow down - but it wouldn’t do to drive around with the regenerative brakes on!
Jon Mooeing: You have an interesting new variation on an old idea. Providing power from overhead lines has long been applied to trains, and electric busses in places like San Francisco. If the expense of building and maintaining they system isn’t excessive, it could be economically successful, but the main drawback would be getting political support and loud complaints about “ugly wires blocking the view”.
A similar proposal would use overhead “tow-motors” to literally pull vehicles along the road, usable to any “towable” vehicle. Other variations would hide the power supply in a guardrail alongside the road, or use electromagnet coils buried in the roadway to transfer power by induction, or even use a linear motor drive embedded in the road to propel the cars.
Another idea is to use “powered guideways” that would isolate the vehicles from pedestrians and regular traffic, and fully automated to provide convenient, safe, rapid and efficient transportation between cities. Just drive to the nearest guideway entrance, punch in your destination, then you could relax, read, play games or snooze until you got to your designated offramp, where you’d once again take control and drive to your final destination. For more information on various “dual mode” proposals, see:
faculty.washington.edu/jbs/itrans/dualmode.htm
Brian Covault: Tesla Motors is considering a “swappable battery” for their upcoming Model S, as it would certainly be a fast and convenient “refill” when on a long trip. A company called “Project Better Place” is also designing an EV battery swap system, though I don’t know if Tesla is cooperating with PBP on it. The car owner would lease the battery from the “swap company”, and when needed would just swap one leased battery for another, charged only for a “swap fee” and the charge of electricity, and credited with any remaining charge in the old battery.
For everyday local driving it would be more convenient and cheaper to just plug-in to recharge at home or any “park and charge” lot, rather than have to drive out of your way the nearest battery swap station. By the way, Tesla plans to install high powered “45 minute max” charging outlets for the Model S, perfect for the traveller - just stop at a hiway diner with a “fast Park and Charge” lot, take a break, have lunch or a snack, and when you’re ready to go again, so is the car!
The Roadster didn’t include a “swappable” battery, as it was enough of a challenge just to make this new type of battery pack work right, without having to worry about swapping.
Thanks for the positive feedback CM.
I’d like to take modest little babysteps with my smart dollie overhead rail system by building a small subscale example course on Mammoth Mountain that powers electric mountain bikes up ski runs. Ideally two side by side course runs would enable two riders to compete in the sporting event sense of a timed uphill race.
I think it would be a commercially viable means of showing the CARB officials the system’s potential for interstate applications for both semi-trucks and passenger EVs.
A new x-treme biking event utilising clean electric full suspension mountain bikes in California would sure help raise the awareness of EV potential in our younger generation.
The electric bike’s power to weight ratio would certainly make for a thrilling uphill ride, complete with all natural rushes of adrenalin.
We need to show the public that clean new EV technology is superior to yesterday’s polluting relics in every sense, faster, lighter, better handling and quieter.
Once CARB is convinced the system works and could be applied to our interstates, it becomes a symbiotic relationship between the state, private EV owners and commercial trucking companies going green.
There’s an all electric battery powered semi-truck being tested right now at Long Beach Harbor cargo terminals here in CA.
Thanks for the feedback CM.
Wayne P. Bishop,
What you are illustrating is constant acceleration made by constant torque. It is true that it is possible to increase RPM without increasing use of force, eMotor does that for wide range of RPM.
Torque is pretty close to force IE. F=ma, which gives a=F/m, only that in torque F is now force that causes change in angular velocity which depends of radius of the rotating object. t=rF or F (force causing radial acceleration) = t (torque) / r (radius of the wheel).
Now this gets a bit confusing: When you apply power to the motor (floor the accelerator or in your case fire the rockets) input power is constant and you get constant torque, but output energy is not constant and is increasing in the rotating wheel. You are transferring energy from those rockets to that wheel that accelerates. The faster it goes, the more energy it gains. In car that manifests itself in increased kinetic energy of the car itself.
I think there is what confuses you: with your rockets you are applying constant power, but because energy is power * time you are not applying constant energy.
Problem with your transmission claim is that you are claiming that you can do that with transmission which does not apply any power source like those rockets in your example. When you increase RPM with transmission you lower torque output that input power source is giving you. In a way you are decreasing radius of the rotating object: same thing as when you use your bicycle and switch to larger rear cogwheel to smaller one in order to increase rear wheel RPM without needing to increase input RPM. t=rF and if r gets smaller t gets smaller too. Or if we include power in calculation P=t*angular speed or P(kW)=(t(Nm)*2pi*RPM)/6000. As you can see we can’t increase RPM without increasing P unless we also decrease t.
In theory (not in real life) it could be possible to build electric engine that does not lose any torque at any RPM which would mean constant acceleration force at any speed. Note that because there is friction which increases as speed increases that would not mean that you could accelerate from 60-120 as fast as you could go from 0-60.
I know this is quite confusing. force/torque/power/work/energy etc. and their relationships are not always easy to understand.
To engineering: About touch screens.
Have you tested how well those touch-screens behave in very cold climates when car has been parked for some time? Both Type S and Roadster utilize touch-screens for multitude of functions (including typing PIN-code to start it). If temperature is somewhere in -25C region do those work at all? I kind of don’t trust on touch-screens in cold weathers. Do I need to carry portable hair-dryer in order to melt that touch screen first before I can start the car?
In Type S that center console touch-screen is huge. I would prefer more standard set of controls so that I know where my hand is without needing to look at. It is safer that way. Could you provide Type S without touch-screen controls for AC/fans/radio/stereo etc? It looks cool but I’m not convinced that it is practical. In fact I believe it to be anything but practical. Screens should be mainly for information, controls should be accessible without needing to look at what you are doing.
Wayne Bishop:
“The rockets are burning(expending) the same amount of fuel every second and thrusting with the same force, and therefore the same torque, as it did at the lower rpms and even at 0 rpms. Where does the extra energy(power) come from due to higher rpms?”
The energy comes from the continuous burning of rocket fuel. It causes the rocket propelled wheel to rotate at an accelerating rate increasing its kinetic energy. That is the same effect that a rocket has on propelling a missile to higher and higher speeds increasing its kinetic energy. It does not matter at what rate the fuel is being burnt. The more fuel burnt the more energy is generated in the form of higher speed motion or increased kinetic energy.
I got a chance to test-drive a Roadster recently, and was very impressed. But it has one driving trait that I hope is not passed on to the Model S (I am customer #717 for the S). That is the rather high built-in regen braking that occurs when you take your foot off the gas. It feels like very pronounced engine braking, like when you wind out a gas-powered car in a low gear, and then back off the throttle:
I would very much like to see a driver-adjustable “engine-braking” regen setting for the Model-S. Set it high for performance driving, low for regular driving. Long downhill ahead? Turn it to just the right setting. Heck, turn it off altogether and coast. Some might argue that we need every bit of regen braking, but I don’t see how this kind of aggressive built-in regen helps all that much–if the excessive regen causes a more rapid deceleration than you want , you just have to step on the gas to get back to the speed you wanted to go, using up the regenerated power. With regen turned off, you get no regen, but on the other hand the car coasts along and doesn’t need more engine power to maintain speed.
It seems to me that the best kind of regen braking is that generated by the brake pedal–which the Roadster doesn’t have. This is a major design flaw. Even the Prius has brake-pedal-actuated regen braking. I hear that one problem the Prius has is rusty brake rotors; driven gently, the car virtually never uses its brakes to stop.
So here’s my plea for you Model S engineers: pedal-actuated regen brakes, plus a driver-adjustable built-in “auto” regen to simulate the feel of engine braking when you back off the throttle.
Got an idea.
This might cost a bit to produce, but all the components are here already:
Contract with Daimler and Tesla expertise of EV.
How about we build few “proof of concept” EV:s for Formula 1 pace/medical cars. That would have quite a bit marketing power. I expect that it would impact general public much more than anything else done this far.
Traditionally for some time now those F1 pace-cars have been Mercedes-Benz AMG cars. Previously Tesla cars would have very slim chance to get there as pace-cars, but if you get Tesla components fitted in Mercedes as Tesla/Mercedes hybrid, it is much more possible.
Reading from www.autoblog.com/2009/03/27/mercedes-benz-sl63-amg-returns-as-f1-safety-car-for-2009/ it seems that Roadster would have faster acceleration than what they are using now, but lower top speed. Because F1 race car top speed is way over 300km/h, and even average speeds can be over 200km/h pace car that goes only about 200km/h would look like snail in front of fighter jets. In fact too slow pace car is dangerous to F1 cars, because they need speed to keep tire and brake temperatures high enough. Some improvement would need to be done for top speed. Also cornering speed needs to be quite high (that’s where difference between ordinary car and F1 car is most obvious).
Of course if you could use that 175kW/kg battery tech for 60mAh/g (180Wh/kg) batteries, power would not be a problem. Make 60kWh battery pack that could deliver something like 80000HP (not a typo, (60kW / 180W) * 175kW = 58MW). You would only need PEM, transmission and eMotor that can handle around 1MW power and you can have 300km/h top speed using 14kRPM single gear transmission without sacrificing acceleration.
Of course then we have slight problem with 60kWh. Is that enough? Race-conditions are so much different than ordinary road conditions that I’m not able to estimate how long does that last. Also for pace-car how fast is fast enough? Do you need to accelerate entire Fuji-circuit nearly mile long straight, or would it be sufficient if you satisfy to around 250 top speed (Bernd Maylander says that he can reach 155mph at Silverstone straight with his pace car. That’s slightly under 250km/h) How about regenerative braking? How much energy would you be able to collect back if you max that capability (which Roadster doesn’t).
I believe building a BEV pace car is entirely possible, but not very easy. It could be good advertising for EV:s in general, Mercedes-Benz and Tesla. (at least if it is made clear that that pace car has Tesla drivetrain).
Timo;
Agree about the touch screens. Attempting to make car controls sexy graphic electronic is asking for trouble. If the screen fails, e.g., the car is unusable.
Forget digital displays etc. for basic control and driving functions. They are not robust enough for real world demands.
To Timo
I strongly disagree with you on the large touchscreen.
It is untrue that if you have standard buttons, everything is better.
Get in a new car that you dont know. I bet you wouldn’t find all the
buttons right away. You would have to get used to it. Same with
the touch screen. You will get used to certain algorithms of movement.
Two replies about touchscreen in two days.
To tomthemd: Touchscreen does not give you any feedback of where your hand is, ordinary controls do. It would be much harder to make adjustments to for example CD-player volume or cabin temperature setting if you don’t even know what the setting is or where it is. Especially if that screen has multiple modes which means there is no fixed place for any control. I don’t mind having that screen, I just don’t like the idea that it replaces all ordinary center console controls.
I also don’t think touchscreen is eye-friendly in dark roads. Even bright backlight of ordinary speedometer gets annoying when you are driving in dark roads, not to mention something that is many times bigger and needs backlight to show you what you are doing. You should be able to turn it off and still be able to make adjustments to settings.
Then there is that question about very cold weather. Does it function at all? How about adjusting something wearing gloves? How about with mittens? What is the freezing point of the screen?
Joe Simone:, CM:, Timo:, JB Straubel: Engineering:
In response to your comment of July 31. I can understand the accumulation of kinetic energy depending on how much mass is involved which would mean how long it would take the rockets constant 10 ft. lb. torque to get the system to 1000 rpms, however, what momentum(kinetic energy) you would have at 1000 rpms only comes into play when you are trying increase or decrease the systems rpms. The 10 ft.lbs. of constant torque from the rockets is still there at any rpm and if you apply a 10 ft. lb. load on it at any rpm it will remain at steady state at that rpm no matter what mass is involved and if that rpm is a steady 1000 rpms with a 10 ft. lb. load you can gear it down with a 10-1 ratio and then you would now have a system at 100 rpm with 100 ft. lbs. of torque but when the rockets SAME energy output was at 100 rpms it was still 10 ft. lbs. of torque. Doesn’t that mean that, within the laws of physics, you can apply(not “change to” by gearing) the same torque at any rpm without needing more power? (fact- rockets do just that) Everyone sees how it is possible in rocket physics( which means it IS physically possible right? ) but when it comes to wheel-to-ground physics and they are now dealing with two separate frames of reference, they say it is now somehow “mystical” and, by the laws of physics, impossible. It is only “mystical” because they don’t know how to do it not because it is impossible. With the AST (All Speed Transmission) I can “apply” an available torque (motor) directly to a higher rpm system (wheels) without gearing up to do so, which would decrease torque. It is possible within the laws of physics as seen in the rocket example and if it is “possible” it can be done but only if one can imagine HOW. I can show you how but unfortunately people have to believe it CAN be done before they will ask to be shown how.
Just a side note if anyone at Tesla is interested:
I also have a concept for a TRUE “positively driven” IVT (Infinitely Variable Transmission) that I thought of prior to the AST concept when I was still thinking in terms of gears (ratios). Again it is NOT like any known CVT or IVT in development today. In other words it does NOT use cones, pulleys, belts(steel or otherwise) and is NOT planetary, Toroidal, or incrementally driven. My IVT is continually driven and easily infinitely varied while under HEAVY torque load. There is no slipping under heavy torque because it is “directly” driven. Whoever sees it will say “OH, I see, THAT’S how to do it” Another amazing feature inherent in it’s design is that torque(from wheels) is transferred TO the transmission as the transmission is down ratiod but NOT from the transmission to the motor. However the motor remains connected to the transmission. This means the transmission, (that can take heavy loads), can be used entirely for breaking. If the transmission is ratiod to 0 the wheels will slide. Can you imagine 18 wheelers and automobiles with no breaks to ware out, burn up, or needing servicing? You know that would be worth a billion$ right there. Take care all. Wayne
CM,
Thanks for your comments on battery swapping. If it’s going to take longer to swap a battery pack including drive time than it does to charge at home and be more expensive too, I agree that charging is better, for the commuter anyway at the present time. I hope that changes in the future. Until it does, I hope the concept of charging can be sold to the public at large.
The public at large is used to pulling into gas stations for fill ups that take a couple of minutes rahter commuting or taking a long drive. Whether charging or swapping, I think people are going to want a “fill up” of an electric car to take about the same amount of time whatever form that “fill up” takes. This is the age of instant gratification after all.
People could probably get used to charging if they could try it before they buy it. Getting folks to buy it wilhout trying it for several charges will not be easy especially when an electric costs more than a gas car, the battery pack does not last forever and I assume replacing a battery pack is not cheap.
I’ve read about the 45 minute quick charge. That’s certainly better than three to five hours and gives me hope that something like a five minute quick charge may be possible in the future.
By the way, why is it a battery pack can be charged 80% in 45 minutes while a full charge takes three to five hours? I have yet to come across anything that explains that. Is there a heating issue with trying to quick charge to full capacity?
Thanks again for responding.
I was wondering if Tesla had considered the use of new and improved lithium polymer battery technology such as the technology used in Hyperion’s G3 VX line: www.allerc.com/product_info.php?products_id=4563
Right now it is changing the world of Radio Controlled hobbies, to the extent which there is no advantage to internal combustion power, the electric power systems outperform combustion in every way. If this were used in Tesla roadsters, the roadsters could charge and discharge much faster, weigh incredibly less, and could handle more cycles of charge.
Wayne P. Bishop
You wrote: “Doesn’t that mean that, within the laws of physics, you can apply(not “change to” by gearing) the same torque at any rpm without needing more power”
And answer is “yes”. Electric motor already does this in very wide RPM range. I already said that in my first message. You can imagine electric motor as rockets at the wheel if you like. That is the source of the power output.
However. If you move away from to power source and *then* change RPM you change torque.
But enough of this debate, you can just simply tell us your idea, and we can then check it out.
Brian, I think your argument that people are wanting to charge immediately is already proven to be wrong by customer blog. It is enough to charge slowly at home to have full battery every morning. If you are wanting to drive very long road trip, then you just need larger operating radius. I think 600 mile radius is enough for that. With one hour-long break at some servicing station during that trip you get easily 300 mile or more (using current techs) which is then 15 hours of driving at 60 mph average speed + one hour break. 16 hours + 8 hour night sleep = 24 hours.
Just ask yourself: How many times have you driven over 600 miles without breaks? How long did those breaks take?
About that five minute charging: it is not the battery that is limiting that in future, it is capability to safely transfer that much energy at that little time. 200kWh at five minutes needs 2.4MW connection. 2400V @ 1000A. Roadster uses internally something like 500A connections between engine and battery (375V connection to 185kW engine).
XCraft: Hyperion’s G3 VX line batteries are not especially high energy density batteries. I just calculated random few of them using that datasheet and got something like max 150Wh/kg, which is pretty much same as what Roadster is using now.
HP-LG325-0850-3S 11.1V 850mAh 69g = 136Wh/kg
HP-LG325-2500-4S 14.8V 2500mAh 266g = 139Wh/kg
HP-LG325-5000-7S 25.9V 5000mAh 856g = 151Wh/kg
So no revolutionary batteries there.
Tesla are monitoring new battery techs and will use combination of price, reliability (quality) cycle capacity and energy capacity as measurements of what to use. There is no point of changing those battery techs all of time (logistics, etc.), just do it when there is clearly better battery available.
There *IS* coming way better batteries (one prototype with 540Wh/kg already tested last year), so improvements are in horizon. Imagine Roadster with 800 mile range, or over 200 kg lighter battery pack and still 400mile range. And it doesn’t stop there. There are few techs that have theoretic capacity of over 2kWh/kg. How about 3600miles? And that’s not all, also power densities are improving, one of them allows 175kW/kg power density (meaning 200kg battery could give out 35MW meaning power to outrun nitrodragsters). And that’s not all, you get this knife set ….oops.
Timo,
Then again there are messages in the blog speculating on future infrastructure in or above roadways to allow charging on demand as you drive which tells me at least some people would prefer not to stop and charge at all.
And then there is your last message about batteries on the horizon with far greater range. The horizon is really looking good.
The question is, do you see us getting to the horizon without a lot more people buying the high end electric cars of today such as the Tesla cars? Today, I’m thinking the Model S with the 300 mile range option is almost overkill for commuting. Yet, if I want to take the family for a weekend get away to a major city three hours away, I’m not going to make it there and back on one charge. Where am I going to recharge? So, I’m going to need a $45K electric for commutes plus a $20K+ gas model for the longer hauls.
If we can get just to the 600 mile range while the electric car is still a niche market, beyond 500 miles, many people would just fly anyway.
I’m just trying to envision the path to mass market.
That’s a great patch of data. I voted for you at Design News’ “Engineer of the Year”, and not just because you had the best hair. Congratulations in advance.
Wayne P. Bishop, your “IVT” sounds interesting, have you made a working model to test it? If so, you should consider getting it patented, because a reliable variable speed transmission that can handle high torque with no slippage has been the goal of automotive engineers for a century. If it works well, there are plenty of auto companies that would offer a lot of money for it. I’m not sure it would be a good idea to use it for regular braking, as locking up the wheels would trigger a skid. But it could make a good parking brake, though.
It took me awhile to realize what was wrong with your “rocket wheel” analogy. As I pointed out, rockets are self-contained, their “reaction mass” is accelerated along with the rocket, enabling a constant thrust regardless of speed (but as the rocket fires, the mass it carries decreases so acceleration increases). The same is not true of electric motors or cars, both rely on outside materials for their “reaction mass”. If you run a motor by itself, not mechanically connected to any outside mass, it won’t budge at all. Since the “reaction mass” isn’t accelerated like it is for a rocket, neither wheel motor nor car can maintain constant torque or thrust the way a rocket can.
Brian Covault, the time it takes to recharge a battery depends on 3 factors:
1) the amount of energy that is required. A partially discharged battery takes less time than a fully discharged battery.
2) The amount of power available. Power is the rate of flow of energy, higher power means more energy transferred in a given amount of time, meaning faster charging (assuming the batteries can handle the higher charging rate).
3) The power limitations of the batteries themselves. Some types of batteries can handle higher power than others, thus can be charged more quickly (assuming higher power is available).
So how long it takes to recharge depends on which of those 3 is the limiting factor.
The reason why a charge from 50% to 80% can take less time than a charge from 80% to 99% is that, for some batteries, internal resistance increases when it nears full charge. That requires a slower charge rate when it gets closer to maximum charge. An analogy would be like filling a bucket with a valuable liquid. At first, you could run the hose at a high flow, but when you got near the top you’d want to reduce the flow to avoid overfilling and spillage, that last little bit would take the longest.
Brian;
What are you doing while you’re at your 3-hour distant destination? If any of that time is spent parked, it could be used for a partial recharge. Anyway, 3 hours there and 3 hours back on the same day is a lot of driving for not much time at destination. I really wonder how frequent such trips are. In the real world, I suspect such problem situations are fairly rare. You can, of course, concoct any number of them from your imagination.
Timo,
Sounds promising!
Are you at liberty to discuss any of the companies names for investment opportunities? About the batteries you are using now, I was under the impression that they were old fashioned laptop cells, is this true? That’s why I assumed that the new lipo technology would provide better energy density and power output. Likewise, I would assume that A123 and Altair Nano’s NanoSafe technology would be better as well.
‘If we can get just to the 600 mile range while the electric car is still a niche market, beyond 500 miles, many people would just fly anyway.
I’m just trying to envision the path to mass market.’
can you imagine scientists that are to stupid to think.
1/ oil is running out and environment protected areas have to be destroyed to get the last drips.
2/ we have oil sands! ,which we use the last resources of water to get the oil out in a quickly drying out earth that is already catching fire in the wetest areas. So our drinking water is going for getting out oil we will just burn and cause more pollutants..
3/ If the oil disappears we will use our food resources to create more oil so we can burn it as gasoline and pollute the earth more.
4/ (already we are all too stupid to live)
4b/ As the pollutants in the air increase the pollutants go to the arctic areas making the ice black which will absorb sunlight making the earth hotter and melting the ice causing a two or more fold result of super storms that destroy the costal areas and the heating of the earth which will dry out and burn the grass and trees which will cause a loss of oxygen which will cause an increase of death from lack of oxygen.
5/ … (It gets worse)
Brian Covault:
“The question is, do you see us getting to the horizon without a lot more people buying the high end electric cars of today such as the Tesla cars?”
Not with current models, no. We need a bit more affordable models with at least 400-500 mile ranges to make real breakthrough. 400 miles is only about six and half hour drive which is still desirable. Longer and I would consider flying instead. I would imagine something like $30k car with 450 mile range would make real breakthrough for BEV. $57k Type S is still too expensive for just 300 miles. And I believe that 300 miles makes that price-tag a bit higher (somewhere in $65k I would guess). Then it is just matter of marketing so that general public gets aware of those cars.
“Yet, if I want to take the family for a weekend get away to a major city three hours away, I’m not going to make it there and back on one charge. Where am I going to recharge?”
We need charger infrastructure, yes. That is not yet here. Capability is. I believe any roadside restaurant can charge cars with several kW connection (just 380V three phase @ 100A would be 38kW which would charge 300 mile worth in about two and a half hour). Because so much of the charging will be slow opportunity charging in places like workplace parking lot and home there is not much demand of those chargers except to draw people in. It definitely will not be like gas-stations where people might actually need to queue to get gas.
I imagine situation for those slow charger points is worse in there than it is here in Finland. We need to use block heaters here in winter, so every other park space has one “slow charger” already installed.
Three hour drive there and back is six times…lets make 70mph average speed so there is some margin… 6*70 = 420 miles. Electricity is available pretty much everywhere, so you can slow-charge in your destination. Even just 110V@10A is 1.1kW. With that is takes you about 31 hours to charge that missing 120 miles worth of 300 mile range (40% of 85kWh Type S battery = 34kWh). Two nights and some of the day. for Fri-Su that is two 10 hour nights and five hours daytime from fri and sa. Su is for driving back. (BTW, how much amps usual home connection has in US? In Europe we use 230V system, so my figures might be badly wrong). And if that is not fast enough then there might be higher wattage connection closeby in some restaurant or something like that.
“If we can get just to the 600 mile range while the electric car is still a niche market, beyond 500 miles, many people would just fly anyway.”
Exactly. 600 miles is more than probable, it is more like inevitable. With 540Wh/kg prototype battery already tested in labs, that would make 600 miles (in Type S size car of 200kWh) roughly 370kg battery. About 50kg smaller than Roadster battery. Usually in these high-tech products final product is even better, so I wouldn’t be surprised if real capability is somewhere in 600-700Wh/kg class. That was also better in cycling capability and because it replaced graphite with silicon it wasn’t flammable.
“I’m just trying to envision the path to mass market.”
I’d say it takes slightly cheaper car with higher range. Type S is, like you said, a bit overkill for commuting, but not quite enough for longer road trips. But with better batteries I believe things will change. The more there are BEV:s in roads the more interest they draw from power companies too. Fortum in here has already build some chargers in Sweden and Finland and there is some kind of Europe-wide standardization going on for high-voltage chargers. There is a lot more than just Tesla happening just now.
CM,
As far as my IVT concept goes, I do not have a prototype but the principle or method is pretty straight forward and anyone(engineer) that looked at it could see how it would work. It would be like showing somebody the principle or concept of a “gear” for the first time. You wouldn’t need a prototype to see that it was feasible and would work. It just needs to be engineered / developed and it is relatively simple. By the way, if integrating an “electric drive” with this IVT would make it VERY unique.
You are right, the fact that it CAN NOT SLIP because it is positively driven and, “is what every engineer has been looking for,” will make it a tremendous success among automotive manufactures. It has been very difficult to get to the right people in the “Big Three” auto manufactures. I did get an email from GM’s Supervisor of Plant Engineering Dept(Romulus Engine Operations), Oscar Sosa in response to a blog I put on GM’s “Voltage” blogs” about my ASTM concept and he said he was interested in finding out more about it but when I emailed back to him asking if it would be ok to call him I didn’t here any more back. He probably showed my blog to someone(engineer) that said it was impossible and that was that. I have messaged and emailed a number of IVT and CVT manufactures recently. This IVT is a BREAKTHROUGH concept and when I get a number of companies seriously interested I plan on obtaining a Provisional Application for patents on them (only takes a couple weeks) and then show them to the most promising company. If you know any company or have any contacts I would appreciate it very much if you could put me in touch with them.
“Why is it so hard, and takes so long, just to CHANGE THE WORLD?” lol
I want to clarify my IVT’s braking capabilities. It DOESN’T just lock-up the wheels. I just said that to show that the design was strong enough to handle full braking(locked-up wheels at speed). Even heavy vehicles like 18 wheelers. This IVT can be ratiod down slowly for light braking or quickly for fast braking. Whatever ratio the transmission is varied too, the wheels will go there. This IVT could be used for a braking system alone. Whoever sees it will see how that works. It is really slick, and simple and different then any IVT or CVT in use or in development today. There will be another “type” added to what’s known now when it comes out. Take care, Wayne
CM,
I forgot to respond to the end of your last comment to me of Aug. 7th. about my “rocket wheel” analogy where you said, “Since the “reaction mass” isn’t accelerated like it is for a rocket, neither wheel motor nor car can maintain constant torque or thrust the way a rocket can.”
Here’s the thing, and this is IMPORTANT to grasp. Until rockets came along the propeller propelled aircraft community(aero engineers) felt the SAME way about thrust. They said, “You can’t have constant thrust without more power because the air you are pushing against moves away faster and faster as the speed increases.” They couldn’t imagine constant thrust at ANY speed - JETS. So they tried to improve on propeller design, improve aerodynamics, increase engine efficiency and then said, “The ONLY way we will get more speed is with more power and more RANGE out of our aircrafts is to carry MORE FUEL.(sound familiar?) The engineers of today are saying the same thing about wheel-to-ground vehicles, They say, “The road we are pushing against is moving away faster and faster as speed increases so there is no way to have constant torque at ANY speed.” So they try to improve transmissions with CVTs, IVTs, better aerodynamics, increase engine efficiency(electric motors) and then say, “The ONLY way we can get more RANGE out of our vehicles is to carry MORE FUEL (bigger or better batteries) , But just like the breakthrough for “constant thrust” there is a breakthrough for “constant torque”. And it is NOT a jet engine on a car or wheel. It is the ASTM (All Speed Transmission Motor). Take care, Wayne
I don’t see in any of your blogs how may Watt hours it takes to fully charge the batterys from dead. Also how many dollors will it take for that charge. Right now power cost about .12/KWh (how much for a fill up it not free)
I hve an idea to make these electric car’s run under their own power. never needing to plug into the power grid. It so simple I can’t believe That smarter mind haven’t figured it out. Im an oilfield worker by trade but love the idea of useing less gas and oil for fuel. Would like to share my idea with the wright person our group.
John, Roadster battery pack is about 54kWh pack, and with losses charging takes little bit over 60kWh. So 60*0.12 = $7.20.
Xcraft: I don’t work at Tesla, so they are not “my batteries”. I just have been watching this website for a long time and know pretty much everything someone has written here at some point. Roadster batteries are laptop cells. Energy density can be estimated from data in this website (Battery pack total weight: 450kg, capacity 54kWh). Look at “more” tab in top of the page and there “white papers” which has pdf of battery pack.
Altairnano and A123 batteries have very high power density but not high energy density, so they are not very good for for large operating radius BEV. They would be for hybrid for because they have high cycle durability and small battery gives a lot of power.
Dear Tesla Motors:
We are commercializing our RET, high efficiency, low cost, green, light weight, multi-fuel thermomechanical engine or powerblock. Our initial products are multi-fuel (including biofuel, CNG, Diesel, Methane) off-grid transportable generators. We have started a Green Car Initiative realizing our RET-GENSET can be sized to provide, green, light power (mechanical and/or electric) for autos. We have extensive collaborative access, and have been invited to discuss with a powerful, well funded government, engineering center. US based Energy, Materials, Manufacturing is of US Strategic importance and dovetails with RETs high fuel efficiency (150MPG) and related green technology! Most auto manufacturing in the USA is assembly, not engineering/ IP which is being offshored, outsourced. A RET propelled Cooper type sedan would get 150 MPG. We are seeking automotive chassis manufacturers with electronic controls; large scale composite manufacturing assistance (technical, financial) will come from known Federal funded centers. A RET-Telsa could replace 2/3rd of its battery volume/weight and achieve superior performance (its lighter), as well be fueled at any station, thus have unlimited range. This configuration will achieve 150MPG H’way on fuel. A RET Hybrid Duty Cycle is 600,000 miles. A 150 MPG RET powered US NGC (New Green Car) Cooper Sized, selling to the public should not exceed $6,000. However, composite may cost more, than current estimates using steel and plastics. National, international markets, workers, green enthusiasts/ promoters, US cmcl/govt fleet sales, foreign cmcl sales. 100,000 units could be a pre-sold beta test, factory would be sized for over 1 million units, flexibly manufactured, readily available, land with lots of incentives. A high tech new Detroit. A paradigm changing affordable, automotive suite of products, will not want for stakeholders. Discussions with “bigs” frustrating. Perhaps a high tech affiliation is better than score years of experience making legacy products. NB if the government provides $4,500 cash for clunkers at the right timing, (again) then a RET NGC would cost the consumer$1,500. JR CEO SPI Sannerwind@gmail.com
Wayne P. Bishop: Coming up with a bright idea is just the first step. There have been many bright ideas that had some subtle flaw that wasn’t readily apparent, until they tried and failed to make it work. Engineers are often bombarded by folks who have a bright idea, but then they find it doesn’t really work because they’ve overlooked some minor point - maybe too much friction, or a part that collides with another part, or the kinematics is wrong, or some other subtle error.
Having an actual working model will prove that it works and the idea is sound and you hadn’t overlooked some obscure point. Having a working model that you can show makes a better impression on the engineers you are trying to reach, even if it is a simple plywood and plastic model, or just something cobbled up from cardboard and string. A working demonstration is much better than saying “I’ve got this great idea” (which they’ve already heard waaay too many times).
John: how much energy it takes to recharge depends on how much was used, charging after a short drive takes much less energy than charging from “fully drained”. The maximum recharge would take about 60 Kwh, at 12 cents a Kw it would come to $7.20, just as Timo said. But of course, most days you’d be driving less than 244 miles, so the cost would be less. You definitely want to avoid “fully drained”, just like avoiding an empty tank in a gasser.
Randal Ray McMullin: If you will scan back through previous posts in this blog, you will discover that there have been many proposals over the years for “self-powering” or “eliminate the need to charge” or “greatly extend range”. Unfortunately, they have all been impractical or don’t work. Covering the car with solar cells increases costs, but adds at most 5 miles a day, so it isn’t really worthwhile (that could change if costs drop and efficiency improves).
If your idea involves attaching a generator to the wheels or the motor, or attaching a windmill to the car, then you haven’t realized how much drag those devices can produce. Most EVs and hybrids can use the motor as a generator to partially recharge the batteries, but the electrodynamic drag it produces slows the car down - it is called “regenerative braking”. Good when you want to slow down, but very bad if you want to cruise along or accelerate.
If your idea involves some unknown energy source, we’d better learn all about that energy source first. Nuclear power turned out to have some unexpected hazards, we don’t want to unleash a new hazard to the world. If your idea involves violating the known laws of physics, you’ll be making an extraordinary claim, and we’ll need some extraordinary proof before even considering it. There are just too many crackpots out there.
Is Tesla Motors a public company listed on a stock exchange?
SHOULDN’T ELECTRIC CARS BE HELPNIG PEOPLE???? INSTEAD THEY PRICE THEM 4 TIMES AS MUCH AS A NEW GASOLINE CAR….SEEMS TO ME I HAVE TO WIN THE LOTTERY TO DRIVE ON OF THESE….WHATEVER
Imagine an electric car freed of heavy, space-consuming mechanical components which only gasoline cars need, such as: clutches (including engine-to-wheels fluid couplings, i.e. ”automatic” transmissions), drive shafts, or differentials.
An all-electric power train, centered on a mechanically independent electric motor for each wheel, would do this.
Maybe each motor could be strong enough for 1/3 of the whole car’s power needs, to hedge against one motor’s failure. That would “overbuild it” to be better than “good enough”. An instrument panel warning light (maybe with beeper?) might communicate such a motor failure to the driver.
An underframe designed around a center-sill, leading, through several side bolsters, to lighter body-supporting side-members (like a railroad car’s frame) could support the concept. Firmly attached to the center-sill, would be each wheel-motor. From there, with a universal joint at each end, would be that wheel’s axle. Suspension could follow some conventional four-wheel independent suspension arrangement.
Might its bigger battery bring range between charges (at a steady 65 MPH cruising speed) from 200 miles to, perhaps, 300? Maybe.
I will grant you, in advance, that its all wheel drive might seem best suited to an SUV but, it won’t hurt a roadster or sedan to have it either. All owners will be glad to simply drive out of “hopelessly” miring snowbanks, or mud. Deep snow last night? Why clear the driveway? Road not plowed? Wouldn’t it be fun to unplug the car and just drive out?
Since you are starting relatively freshly, why not use this platform under the entire Tesla fleet, so that all models can benefit from its mass-production savings (with fewer components to build separately)? That can let you reach competitive (maybe more than competitive) pricing earlier in its ramp-up of production.
Much weight and space is freed up for battery and – well – the rest of the vehicle!
What do you think of that?
John Doe: No, high-end electric cars are not made for treehuggers, this is pure business and Tesla Roadsters are simply high-end sport cars. The fact that they help environment and kill polluting gas guzzlers is just bonus to their attractiveness. Cheaper models will follow that even treehuggers can afford, but it still is business, not charity.
Tesla Roadster is quite cheap for its performance. It is as agile as Porsche GT3 which costs a bit more than Roadster and loses to Aston Martin DB9 only teeny weeny bit in performance. Aston Martin DB9 costs nearly twice the Roadster price. Type S will be bargain in performance/luxury -scale. Roadster sport (AFAIK) beats nearly all factory-build sportcars in quarter mile.
With new battery techs coming it will be possible to build BEV that could beat nitrodragster in acceleration (with right tires) and would still be safe and economic to drive in roads.
The motor on each wheel sounds like it has a lot of advantages. I eliminates the differential, single speed transmission etc. It sound like it would reduce the drive train losses which are second to the aerodynamic losses. The control is all in the digital electronics and inverter. However Tesla addressed this in one of their earlier blogs and claimed that a motor on each wheel increased the unsprung weight (the weight below the suspension). It claimed this produces poor handling.
I know that the Electric Mini (www.treehugger.com/files/2006/08/the_hybrid_mini.php) and the Lightning (www.autoblog.com/2008/07/09/lightning-gt-ev-sports-car-coming-this-month/ ) have motors on each wheel (hub motors).
Don’t forget that 4 motors, single speed transmissions, and controllers COST MORE and weigh more than 1 motor and 1 controller. You can argue that smaller motors/controllers would cost less than a larger version, but not much, each would be over 1/2 the price of the single larger version.
The only way to finance new expensive technology is to start with high-end products. Over time with increased demand and sales, the costs will come down and cheaper cars will be built for the rest of us. We have to give thanks to early adopters, willing to pay premium prices, so we can benefit later.
CM
Thanks for your explanation of battery charging. I understand much better now.
Brian H.
“What are you doing while you’re at your 3-hour distant destination? If any of that time is spent parked, it could be used for a partial recharge.”
This assumes there is a means of charging available. I have not come across any motels with electrical outlets beside parking spaces. I do agree that if you are driving three hours to a destination, you are probably going to be there long enough to recharge. There just needs to be more charging infrastructure before we get to that point as Timo suggested or increased range to avoid recharging away from home.
Timo
Standard household current here in the US is 15 amps / 110 volts I believe. You make it sound like there is more charging infrastructure in Finland than there is here. How far along are electric cars and recharging in Finland? Or did I read too much into your response?
jdsim and David E. Manwell:
I just stumbled upon this www.worldchanging.com/archives/005118.html
“I also asked whether they thought about using in-wheel motors, since putting a small motor in every wheel instead of having one big motor with a drivetrain connecting it to the four wheels can greatly reduce mechanical complexity and weight, as well as improving reliability. (This is one thing EV’s make possible which simply can’t be done feasibly with combustion engines.) Interestingly, they did consider it, but JB said it would have made safety certification extremely difficult. It’s perfectly safe, but the certification regulations are written assuming you have one motor and a drivetrain, so there are some certifications (such as the one for Anti-Lock Braking) you can’t pass in a car with no drivetrain. These rules would need to be re-written to allow vehicles with in-wheel motors to be certified, which is obviously not going to happen without significant money and time spent lobbying–not a fight a small startup company should take on if it can avoid it.”
So it seems that use of hub-motors ise hindered by outdated legislation. Same way I just found out that electric motorcycles here in Finland have ridiculous 12.5mph speed limit. Any more outdated and it would require someone to run in front of it waving red flag. Can’t think what an earth that person that made this law had been smoking. Something that damages brains for sure.
There is mention for Type S that it might have 4WD as option, which I believe would be hub-motors in front and more traditional powerful single engine in back with better efficiency. No real info about that though. Maybe all four wheels are hub-motors. Maybe not.
I got a slight eureka moment this week about electric cars. Tunnels and parking halls won’t need so much ventilation. Gas guzzlers both use oxygen and emit toxic gases, but not EV:s. That means serious savings in closed space ventilation costs, and also increased safety in accidents in tunnels. No gas-tanks to blow up or ICE to use valuable oxygen.
Not a bit point, but one more advantage.
To jdsim:
I may not have clearly described my design’s concept.
My underframe has a major center-sill, to which are attached light lateral members extending to light side-rails, which hold the body.
Though I’ve referred to these four separate, mechanically independent drive motors as “wheel-” motors, (since each drives only one wheel) they’re not, located literally on wheels. Each of these “wheel motors” is rigidly attached only to the frame (at its center sill) not the hub, placing it above (not “below”) the suspension, so “unsprung weight” is not increased. From motor to wheel, power is transferred through its half-axle. The half-axle is attached to its motor through a universal joint, with the half-axle’s other end joining its wheel through another universal joint (to keep the wheel vertical throughout its travel below the suspension This prevents it from tucking under in hard cornering, as the early VW Beetles sometimes did, which often rolled them over). Since only the wheel is below the suspension, unsprung weight is not increased.
Besides the objection you raised to handling, the vibration a hub motor would be subject to would, very likely, not take long to destroy it.
For all four wheels the suspension is only independent.
What I wrote about does not use “hub motors”. Though its wheels are each directly driven by their individual motors, they are mounted above (not “below”) the suspension.
I hope this makes it clearer.
www.sony.net/SonyInfo/News/Press/200908/09-083E/index.html
I wonder if these new Sony Lithium Ion batteries would be an improvement to the ones that Tesla is using. Sony just released them and are using them as of this month, and they can regularly charge 99% of their energy in 30 minutes, and last 4 times as long (reportedly). I am not an engineer, just an interested Tesla fan that likes finding cool news articles about stuff like this.
Their technical specs on the batteries are thus:
Cell type Cylindrical type 18650
Size Diameter 18mm, height 65mm
Capacity (0.2ItA) 1.1Ah
Nominal Voltage 3.2V
Energy Density 95Wh/kg
Power Density 1800W/kg
Max. continuous discharge current 20A
Weight 40g
CM,
About needing a prototype, I would say you are absolutely right for probably 99% of them. As a matter of fact I had an idea back in the 90’s and was pretty sure that if I put torque on this system in a certain way that I would get a particular result. Well to my surprise it didn’t happen the way the thought it would. So then I had to explain to myself what was REALLY happening and why. So I do know what you mean. However I think in some ( all be it very very few) cases if a bright idea can shown with clear drawings and a clear explanation it could be excepted by engineers as workable and they would be willing to move forward with it. But of course they would then build a prototype of their own to test it. I feel that with my PDIVT ( Positive Drive Infinitely Variable Transmission ) concept I could probably get away without needing a prototype for the engineers, when they see it to say “I see, I think you’ve got something here!”. However, since it shouldn’t be difficult to do, I will probably as you said, “cobble up” something to definitely prove it works as advertised and to eliminate the outside chance that I may be missing something. (it’s happened before) lol Now the ASTM (All Speed Transmission Motor) is a different story. It would be much more difficult for me to build a prototype but I guess, with a little help, it could be done. I think if engineers looked at the ASTM they could probably tell if it would work as I claim it would OR they could point out the flaw in the concept. However, my point is, IF a company or an entrepreneur would state flat out that they “will NOT look at any “bright Ideas” unless there is a deminstratable prototype” then they will definitely NOT be the ones that COULD HAVE benefited greatly monetarily or have “Changed the World”. But they could still brag, “WE could have developed that!”.
Brian Covault,
We don’t really have much “EV culture” here. But there is ate least one of the major power companies building charging points (slow ones) around major cities, and when I contacted them in order to find out if there is one between my parents home and my home they told me that there is Europe-wide standardization going on for EV chargers and they are investigating techs to charge cars in 10 minutes (didn’t say how big battery though).
Also there is small scale EV conversion project going on that is in its final stages (www.sahkoautot.fi/eng). Also Fisher Karma will be build here (AFAIK in same factory that builds Porsche Boxters).
Finland is at winter quite cold place (depends of where you live it can get -20 to -40 celcius), so we use block heaters in our cars. That means that we have “slow charging points” in pretty much every residential parking slot and many office parking spaces too.
Brian:
—-
Energy Density 95Wh/kg
Power Density 1800W/kg
—-
Not an improvement. Tesla current batteries have something like 120-150Wh/kg (not sure how much battery pack casing weights). For more range you need bigger energy density, not power density.
High power density though. 1.8kW/kg. Bugatti Veyron 1001 HP (metric HP I guess) is about 736kW. 736/1.8 = 408kg. Tesla Roadster has about 450kg battery pack. How about Roadster that beats Veyron
. You wouldn’t get very far with that power though. Same 408kg battery would have about 39kWh energy, and used in full acceleration it would last 39*3600/736 = 190 seconds. Three minutes from full to empty.
Hallo,
is it possible to use some trailer with battrypacks to get the chance to travel more than 1000 miles without recharching?
Moderator:
I just read some comments on www.worldchanging.com/archives/005118.html and checked them vs your website.
There is at least one real error:
In efficiency tab - well to wheel -tab there is chart that says that Roadster mileage efficiency is 110Wh/km. In this blog JB Straubel has charts that show that roadster real mileage efficiency is more like 220-250 Wh/mile which is 137-156 Wh/km (between 50-60mph). I’m inclined to believe that there are a lot more of this kind of not so obvious errors around this website. (like that power/torque curve chart)
Giving “fuzzy” data is not so bad, but giving out plain wrong information is BAD. Bad for marketing, bad for us that seek out reliable information, bad for reputation (if someone spots it out) etc.
I urge that you and some engineers use few days to go thru all data presented in this website and fix them. After all I believe this is the main point where people find out information about your cars. If there is obviously incorrect information think what kind of signal it sends to people.
The “sqeeky wheel”
Timo Pietilä
Brian, just to elaborate a little on Timo’s remarks about the battery. Tesla uses 2.1Ah 18650 style batteries. These Sony ones are only 1.1Ah. High end cells like industrial.panasonic.com/www-cgi/jvcr13pz.cgi?E+BA+3+ACA4001+NCR18650+7+WW are 2.9Ah. I have suggested before that I think Tesla should offer these premium batteries as an option, would get over 30% more range.
Timo wrote on March 23rd, 2009 at 6:25 pm
“Kevin Cardinale: In-wheel motors may reduce transmission losses about 30% of less than 5% what it is now. So you end up with 3% energy loss instead of 5%. No big deal. In-wheel motors are weaker and less efficient than Tesla one motor solution so you would actually lose some efficiency. Weight is also not a issue here, transmission + shafts don’t weight much.”
I spent some time thinking about EV design in the 1980’s. I lived then, and still do live in snow country. 4 wheel drive was mandatory as design criteria, as safety is reduced with two wheel drive. Since then I have seen information on “pancake” permanent magnet generator/motors that might be suitable for in wheel use. Although you say weight and efficiency gains would not be significant, I have not found support for your claim that in-wheel motors are weaker and less efficient anywhere on this site. Indeed, electrical to mechanical conversion efficiency is not a simple matter, but my impression reading about wind generators using three phase PM energy generators is that they can be very efficient at low RPM. As well, it seems significant advances in magnetic and bonding materials, not to speak of DC to AC control systems may have opened the door to use of this technology for transportation purposes. I would be interested in your comments.
And a side note: I was surprised to read your design uses electricity for cabin heat. I think cabin heat beyond electrical waste heat should be via liquid fuel, not battery. Conversion cost from fuel to heat is much higher when you run it through the electrical grid, and the in vehicle battery. I would think a heater for northern climates could make sense.
jeremy lansman:
Hub-motors are weaker than out of wheel ordinary motor just because they are restricted in design and size in order to fit into wheel. Smaller size generally means less efficiency in electric motors. Also weaker as in breaks more easily. Those motors are subject to enormous shaking in fast vehicles.
Hub-motors OTOH could save space and allow more interesting designs. Especially in some harvesters or somesuch that could have wheels in movable hydraulic arms. Partially walking in extreme terrain, partially driving like car when possible.
I don’t understand your comment about 4WD being mandatory for snow country. Not for safety, nor getting anywhere (as long as you stay on roads). Don’t your country use studded wheels at winter? We have here in Finland about half a year snow and ice (depends of where you go here, in Lapland snow begins much earlier and lasts much longer than in south-coastal areas). We have here all kinds of vehicles, front-wheel, rear-wheel and AWD. Mostly front-wheel drive. All are equally safe. AWD would be useful only for getting somewhere in deep snow. Don’t they teach how to drive in slippery roads in driving schools there?
I believe that in fact well-behaving rear-wheel or front-wheel drive car is safer than 4WD car in speed-induced slide. 4WD car tends to lose grip in all wheels at once, and getting back to control is much harder than with two-wheel drive car that gradually loses grip in front or in back first. You have more time to react and get control back. 4WD is safer only to unskilled driver that has no experience of driving in slippery roads (just because you lose grip later with 4WD). That is at least my experience with cars (and I have driven a lot of different vehicles, including military ones).
Of course if car is _not_ well behaving then it really doesn’t matter if it is 4WD or 2WD. I have driven one car that was horrendous to drive in slippery road. No warning of slide, one second you were driving nicely and next you were driving backwards or spinning uncontrollably. Car balance was totally off. Scary thing. Braking needed to be slow and carefully considered, hard braking and you are spinning again. Luckily I was only testing that car.
Roy:
Correct my calcs but isn’t that more like 70% increase?
One battery weights 45g
3.6 V 2.9Ah = 10.44Wh / 45g = 0.232Wh/g = 232Wh/kg.
Roadster battery pack weights about 450kg. If we assume 50kg for casing we have 400kg for battery: 400kg*232Wh/kg = 92.8kWh battery pack. That is over 1.7 times Roadster battery pack.
Do you have more info about those Roadster batteries? I can’t find it anywhere. 2.9 vs 2.1 Ah is not 70% difference, its only about 38%. Do those Panasonic batteries have higher nominal voltage? Or are they just lighter than what Tesla uses? Or is it just that battery pack casing is much heavier than I assumed?
OTOH 6800 * 3.6 * 2.9 = 70992 or 71kWh (about). That is that about 30% better.
OTOH 54000/(3.6 * 2.1) = 7142 so that should be 7142 * 3.6 * 2.9 = 74.5kWh which is about 38% better.
Same volume with 30-40% increase in range. Weight could be much less.
38% increase in to Roadster range is 336.72 miles. If we apply this same increase in Type S 300 mile battery we get 414 miles which would be enough for me
.
And those are not new batteries. Few years more and those look like relics from stone age.
Timo wrote on May 19th, 2009 at 1:21 pm
Hey Timo,
Tthank you for ur response to my post of May 19th.2009.
Clearly u answered the best u could . But I remain sceptical on what is the useful end-of-life of ur battery packs.
For U to say 100,000 miles is fine and dandy. But show me one of Ur EVs with 99,999 miles on its original battery pack. A realisitc and fair question in my opinion.
Regards GC
Timo: I will answer regarding motors later, as that takes more thought, is more interesting, and is more important. As to driving in snow country? 4WD (AWD?) is mandatory for me. Snow often accumulates before it can be removed from the road, especially in rural areas. I live and work in areas that are mountainous, so roads can be slippery and cars can start to slide regardless of how slow you drive. Studs do help traction on ice, but, as you know, not on snow. I have AWD, and sometimes need it to get where I need to go. Like up a hill. Or to get unstuck when the car starts to slide backwards out of control. Or to power through a snow drift. Yes, power on four wheels does not help the vehicle stop. All cars have four wheel brakes. So, some people may get a false sense of security when they notice improved forward traction due to 4 wheel power, and think they can stop more quickly. Result? Crash, boom tinkle! Another safety comment? It is nice when in a remote location to be able to get home and not freeze. By the way, I am in Anchorage Alaska. It is already getting cold. First freeze can happen early September, especially at higher elevations.
Timo: Understanding, and designing motors is a field of its own, and not being paid to do this, I just don’t have time or understanding to make definitive statements. I do think that using an electrical system as the power transmission system should reduce costs, power loss, weight, and eliminate that snow catching differential gear box.
Pulse Width Modulation electrical power controllers give us new options to operate motor generators. I would guess that with proper voltage modulation and phase control, polyphase, low RPM, pancake shaped permanent magnet motors can result in efficient (>85%) traction motors, even under conditions of near zero RPM and high torque. I would want to attempt design of a tire supporting wheel motor that does not significantly increase wheel mass. Probably that cannot be done, but it would be very elegant. If not, then I suppose the motor would have to be mounted near the wheel itself, power transferred via a CV joint.
I browsed the internet, and found this interesting article on PM motors as used in wind turbines: people.clarkson.edu/~pillayp/c12.pdf. I spent a good chunk of last night trying to understand this paper. I found but did not digest others. I would like to hear from someone who already knows motors and is working/thinking about this. Thanks for your time. Regards - Jeremy
Galactic Cannibal, your question about battery useful life is a fair one, but it can’t be answered. You just have to settle on results from simulations and assumptions made from road testing. Those show 100000mile useful life. When someone gets to that with his/hers Roadster we get a real-life answer to your question, but it takes time.
Of course in simulations charge-discharge cycles needed for 100000 miles have already been made. Roadster battery pack consist of roughly 7000 small batteries which combined gives 54kWh of power which gives 244 miles of range. 100000/244 is 409 cycles. If individual battery unit lasts 410 cycles with over 80% of capacity you have your 100 000 mile lifetime. There are battery techs that can give several thousand cycles with over 90% capacity so 410 is reasonable. You don’t need to test entire pack for that.
Maybe Tesla has made tests with entire pack. I don’t know. But that lifetime definitely is possible. With future techs you get easily 400-500 hundred mile worth lifetime (battery pack size increases which means range increases for single cycle _and_ cycle capability improves).
jeremy lansman, so you AWD (all wheel drive) is not for safety but for rough terrain. For that low ground-clearance Type S of Roadster are pretty bad choices even if they could have AWD. You need something with little bit more off-road capability. For that I agree that AWD is the way to go. As I said in my previous post I have driven several military vehicles and every single one of those had AWD. Only some sedans for transporting VIP or some generals had two-wheel drive, but those were not really military vehicles.
Of course the vehicle I drove most didn’t have wheels but tracks. It could swim, climb up hills over 50 decree elevation, go in deep snow and swamps, was agile enough to drive fast in forests and generally get pretty much everywhere. Could be fitted with several different weapon platforms. Usually though just for transporting troops. Loved it. Unfortunately it was also pretty noisy which mean that anybody with ears could hear it coming from miles away and it generated lots of heat which made it very visible in heat seeing things even with camouflage, so emotor in that would have been excellent. More torque, less noise and heat.
I wonder how to solve electricity transportation and charging in military equipment. “portable” fusion generator? (focus fusion 5MW generator could be small enough to fit in large military vehicle, if it ever works).
Timo:
I think you answered your own question. All 18650 batteries weigh in about the same range of 43 to 48 grams.
One of the reasons I picked these Panasonic batteries is because they have the same nominal voltage. There are some on the market rated with more AH but do so by discharging to a lower voltage.
6831 batteries * 45 grams = 307kg. Total battery pack weighs over 450kg so packaging and electronics is about 150kg not the 50 kg you assumed. Tesla pack is rated at about 52kWHr / 6831 batteries = 7.61WHr / 3.6v = 2.11AHr.
Panasonic batteries quoted at 2.9AH/2.1AH = 138%, I was being conservative when I said over 30% increase in range, your figure of 38% is more accurate.
Don’t know enough about the Model S batteries. I don’t believe they have been decided on yet. A curious remark by Elon a while back was that the Model S batteries would be much superior to the current Roadster batteries. I assume that if the Model S gets a much superior technologhy battery, that this will also be retro-fitted to new Roadsters. There are many exciting possibilities, but most are “5 years off”. This time is often quoted as the time to bring new technology from lab to market, but in fact can vary widely. I wonder what Elon was excited about, could it be that the EEStor battery will prove to be real after all? I think we only have about 6 more months to find out. I’m even having second thoughts about Blacklight Power which I have long considered to be a scam, Blacklight - run your car on water! Two years to find out if this is real.
Today the ride Steve, owner of Tesla red roadster #33, gave me in Palo Alto was an experience to be remembered. The thing that impressed me most about that roadster was its fantastic get up and go. Also Steve was very knowledgeable about the car, and I do thank him for answering my questions and the whole fun filled experience. Chuck Holmes
Could the driver or passenger be exposed to any electric radiation from the battery or motor? I know people could get cancer for using cell phone too often(still being investigated). I hope there is enough insulation mechanism in the right places for protection purposes. Thanks for any info. - Raye
Raye: Answer to your question is yes and no.
You are subject to magnetic and electric fields in EV, yes, but those have no effect on human beings. Too low power and too low frequency to be even close to even mildly dangerous levels. You get more EM radiation from Sun every sunny day. Using blue-tooth in your laptop in your lap is probably more “harmful” than those are. And there is no evidence that even radio-frequency (except microwave) EM radiation could cause any cellular changes unless it is EXTREMELY intense.
For some birds artificial magnetic fields could be harmful (some of those can see earth magnetic field which is many times weaker than even smallest natural magnet magnetic field, they use it for navigating). We don’t have either magnetic field senses or electric field senses (like some sharks for example, have). I imagine AC magnetic field from emotor is like strobe-light going on and back off in very rapid succession for some homing pigeon.
Excessive use of cell phones causing cancer is probably not caused by radio-frequency EM radiation, but more direct heating of your ear from holding phone next to your ear for prolonged time (I know my phone heats up pretty much and holding it against my ear would heat up my ear too). Heat can cause cellular changes pretty easily.
Why not rethink hub motors? Now that your moving to a more stable and heaver car with a better center mass, maybe the hub motors would not make handling that big of an issue. Also, would that help the range since there is no loss of power from the transition? (One less major item to break)
Roy, I have read one article about Type S having “prototype batteries”. Don’t remember which article it was. Prototype means anything between 250Wh to 500Wh batteries, so can’t say what that means.
EEStor wouldn’t be extremely good for energy density (not anymore) but it would be a lot cheaper making car a lot cheaper to produce. Power density also would be very good, OTOH also lithium batteries have got in totally new figures in it from new invention: 175kW/kg (no that is not a typo, it really was 175 _kilo_watts / kg) with 60mAh/g batteries. Roadster 300kg battery pack could produce 22.5MW power or about 30600 metric HP. 60Ah/kg * 3.6V is 216Wh/kg, so it would be better than Roadster current about 170Wh/kg battery. It also means max recharge speed is calculated in seconds.
That power density is tremendous. Three times nitrodragster power using better Wh batteries than Roadster current. Who needs 1001Hp Veyron when you can have 30000 HP Roadster
. Wonder what would be top speed with that? And how long it would last? For first 0-300mph you would need to limit power output in order to prevent tire burning, so it could last longer than just calculating 67kWh/22.5MW. Also what size of PEM and eMotor would you need to control that power? PEM is quite big object in Roadster.
BTW what is your source of information about Roadster battery pack? I have read that it has 54kWh capacity now. Your text says 52kWh. Small Improvements there? More batteries in same pack? Tiny bit better batteries?
There seems to be a dozen or so posts on this blog about the impact of substaintial heat and air conditioning usage on the vehicle’s range and the affect of tires that provide more effective traction in the snow. These are factors that need to be highlighted in the sales information if thise vehicles and those selling them are to be seen as a reasonable and trusted alternative to what we’ve all done all these years. I think the worst affect of the Chevy Volt ads about getting 230 mpg is the perception that if they would make misleading claims about the perfomance characteriztics, what else will you be unpleasantly surprised with after purchasing one. Trust is harder to regain after being lost.
Raye, If I could afford the Roadster (too expensive for my budget) I wouldn’t worry about electro-magnetic radiation from the car, for two reasons.
First, electromagnetic leakage would represent loss of energy thus lower efficiency. Tesla Motors designed for high efficiency, which automatically means very little low frequency electromagnetic radiation.
Second, the connection between low frequency electromagnetic radiation (AC waves, radio, microwaves, infrared) and cancer was based on a single study finding slightly higher leukemia rates in residents living under power lines, but it did not measure actual exposure to electromagnetic radiation. Multiple studies that measured actual exposure to low frequency electromagnetic radiation found no correlation between exposure and cancer risk, so it seems likely that something else about that particular area under the power lines was causing the leukemia, perhaps related to the local environment or lower income. The only risk of low frequency electromagnetic radiation is if the intensity is sufficient to cause heating it can cause burns.
As for the “cell phone panic”, that was from a single case of a woman who got a brain tumor on the same side that she usually held her cellphone, but consider that there are hundreds of millions of cellphone users, it is statistically inevitable that every year a few of them would get brain cancer, and a 50/50 chance that it would be on the same side that they’d use their cell phone.
I was thinking about the places I would use a Roadster or a Model S. One of those places is my parents cottage. The cottage is about 3 hours /300km from the city. When I get there this is no garage, just a grassy area where the cars get parked. We then take about 15 steps down to the level of the cottage deck. With a 30m cord I can reach the spot where the cars park.
Would it be a problem to charge either current or future Teslas this way? There is no protection from the weather, and it would just be a standard 3 prong ext. cord. I know charging like that would be slow (ah shucks - I’d have to stay at the cottage longer
), but would the lack of a garage or other shelter be a serious problem if rain or snow rolled in?
To “Roy” (August 14th, 2009 at 3:36 pm)
My idea doesn’t use “4 single speed transmissions, … 4 controllers …. (which would) COST MORE ….” with its “mechanically independent electric motor for each wheel”. It simply has a single controller and “all-electric power train” for the entire vehicle. In situations, like cornering, where wheels are temporarily turning at differing rates, one wheel (the slowest) provides the power while the others coast. The only “transmission” is the single, all-electric (perhaps non-electronic) power train; one “controller” handles the whole car.
Where’s the extra cost?
Hey Tesla marketing,
Under any and every analysis, the Tesla Roadster should be at the top of the tables at fueleconomy.gov and www.epa.gov/greenvehicles
Yet the Tesla make and Roadster model aren’t listed at either, even if you choose the “Electric vehicles” category.
I hope you can correct the government’s oversight. The Prius is a fine car, but it’s not the ultimate in economy or emissions!
Thus far all test about cell phones have been negative. If there was a danger from electrical radiation I hope your home is insulated there is more power running through your home and down your block than produced by the batteries in the Tesla roadster. I think the only way to get cancer from electrical radiation would be to sleep in hammock strung between super high voltage power lines.
Timo: It was my understanding that the prototype Roadsters were 54kWh and the production 52kWh using 2.1AH batteries instead of 2.2AH as a cost savings. Been trying to find info to verify, but so far no luck.
David: I admit, I had not thought of your arrangement using one controller for 4 motors. Yes I think it is a good idea and should work, since Tesla’s motors are induction and not permanent magnet. The issue about the transmission is not as straight foreward. Tesla’s motor as designed is a 4 pole motor running up to 13000 rpm. You cannot just hook these directly to the wheels and maintain performance without a transmission. The other alternative is to increase the number of poles, which is what most wheel motor designs do. Some wheel motor designs use a planetary gear to provide the transmission speed reduction.
David: Just to clarify, I agree with and support your 4 wheel design suggestion, with the development of a 32 pole motor.
Speaking to reliability and wear and tear, what is the projected warranty time/mileage proposed for the Model S?
Is tesla previewing to give a solution which permit the car to be charged with solar energy.
) thin film (CIS) solar panel?
Can, for example, the glass roof of a Tesla S ben changed by an optional (or not
xavier, solar panels in cars are not very useful. They are expensive and generally not worth the trouble.
Your suggestion of putting solar panel instead of glass roof in Type S would give you approx 200W charging in midday in very sunny day. Not at all useful at nights, early morning and late evening, cloudy day or shadow of trees/buildings. Charging Type S 300mile 85kWh battery pack would take 425hours with 200W. 300miles / 425 hours gives 0.7miles / hour of charging. If we assume six useful hours worth of sunshine in usual workday at parking you gain 4.2 mile worth charge / day.
Not at all useful. Just too tiny surface area.
However, you can use solar panels at your home. Tesla Motors have some arrangement made with solar city www.solarcity.com/. Check that out.
Hi !
Please, what is the Cd.A of the Tesla Roadster ?
It’s quite difficult to find the info… Is it top secret ? ;o)
Is it the same than Lotus Elise ?
Moreover, could someone tell me what is the energy efficiency, in % , from the outlet to the wheels for different driving cycles ?
In other words, what are the losses (in %) for charger, batteries charge/discharge, wires, electronics, motor, gear… ?
Thanks by advance !
Steve.
Steve, can’t answer to your question about CdA (have wondered that myself, AFAIK it isn’t exceptionally good, just usual modern car. Model S Cd looks better, but it is bigger car so A is bigger), but efficiency question has been answered pretty thoroughly in this blog. Just look at the top of the page.
Engine is very efficient 97%+ at best, 85% at minimum, so losses come mainly from drivetrain electronics and mechanical friction of gearing and shafts. Electronics mainly I believe. I’m not sure anyone knows how much you lose at all different individual points from wall to tires, but overall losses are at top of this page.
Here’s a weird one: an 8-wheeled electric, top speed 230 mph! www.popsci.com/cars/article/2009-08/eight-wheeled-230-mph-electric-car-spawn-bus The “Ellica”. Isuzu is going to make a bus based on the concept, with a 90-mile range.
And Nissan is claiming it will be making up to 100s of thousands of its 100-mile “Leaf” 4-passenger car by 2012, probably in the
Dear Timo,
regarding the question to apply solar panels to recharge battery. I agre with your calculation but some high efficient photovoltaic thin moduls can reach about 80 W per square meter.
And, if you think to apply on a car the bicolor style like this:
wallpapers.dpiq.org/it_17__Lancia_Thesis_Bicolore,_2004.html
you can have about 5 square meters of photovoltaic moduls on Tesla roadster model. It means 400 W, so it would be 1.4 miles per hours of charging.
Maybe it is not a good solution if we look at new car style and efficency results that we obtained, but if you think to export tesla roadstar in a country like Italy for example, it could be a very important solution
It’s just an opinion.
Regards,
Antonio
Pardon the chiche :but a chain’s strength is its weakest link.
The Tesla EV has a battery chain made with 6381 li-ion cells connected in series and parallel. Given the extreme operating environment conditions which an electric car is subjected to like the Telsa EV would be , I think , thisTelsa battery pack is a catastrophic failure waiting to happen. Each connection in this pack is a link like in a chain. And so my question is,Can Telsa’s software-alogrithm find and monitor in real-time the weakest link and thus prevent a chemical melt-down.
In my opinion the best thing about Telsa Motors is their engineering BLOG site . It has a huge collection of mostly sound technical comments.
In the past I have asked for test proof, that the Telsa battery pack delivered 99,999 miles on road driving in extreme temperatures found in Chicago winter and Phoenix summer. TIMO has responded the best way he/she could . But no absolute test proof has been given.
On the battery’s cost side , just look at the statements made by Telsa below, and ask yourself would U pay $36,000 for a replacement battery pack after 100,000 miles. Or pay $12,000 up-front for a pack to be delivered when you reach 100,000. And what about Telsa’s statement that after 5 years or approx(50,000 miles) the battery pack loses 30% of its capacity.
As for the 3 1/2 hours to fully charge the pack , this is for DisneyLand World, and not the “I want it now” mentality world of 2009 drivers……..
Hey TIMO are you a He or a She…………..Regards …GC
—————————————————————————————————————————————-
Tesla Motors refers to the Roadster’s battery pack as the Energy Storage System or ESS. The ESS contains 6,831 lithium ion cells arranged into 11 “sheets” connected in series; each sheet contains 9 “bricks” connected in series; each “brick” contains 69 cells connected in parallel (11S 9S 69P). The cells are 18 mm (0.71 in) in diameter and 65 mm (2.6 in) long (18650 form-factor); this type of lithium-ion cell is also found in most laptop computer batteries. The pack is designed to prevent catastrophic cell failures from propagating to adjacent cells, even when the cooling system is off. Coolant is pumped continuously through the ESS both when the car is running and when the car is turned off if the pack retains more than a 90% charge. The coolant pump draws 146 watts.[63][64][65][15][66]
A full recharge of the battery system requires 3½ hours using the High Power Connector which supplies 70 amp, 240 volt electricity; in practice, recharge cycles usually start from a partially charged state and require less time. A fully charged ESS stores approximately 53 kWh of electrical energy at a nominal 375 volts and weighs 992 lb (450 kg). [67]
Tesla Motors stated in February 2009 that the current replacement cost of the ESS is slightly under USD$36,000, with an expected life span of 7 years/100,000 mi (160,000 km), and began offering owners an option to pre-purchase a battery replacement for USD$12,000 today with the replacement to be delivered after seven years. The ESS is expected to retain 70% capacity after 5 years and 50,000 miles (80,000 km) of driving (10,000 miles (16,000 km) driven each year). Tesla Motors provides a 3 year/36,000 mile warranty on the Roadster with an optional 4 year/50,000 mile extended warranty available at an “additional cost” (2008 Roadster buyers received the 4/50 extension at no cost while later purchasers need to pay). A non-ESS warranty extension is available for USD$5,000 and adds another 3/36 to the coverage of components, excluding the ESS, for a total of 6 years/72,000 mi (120,000 km).[
The Energy Collective features TeslaMotors in “Why Electric Cars are the Future”.
>
If a human body is an electromagnetic field, it for sure would have some level of interaction with the EM radiation from the car. However, nobody knows for certain what extend of harm it would do to it. Of course, there are many affecting factors such as the intensity, duration, and distance, etc. Sometimes the harm could be simply offset by the joy from the driving experience. FYI - now we just found out that there is a direct link between the demise of bees and wide spread of cellular signals - I bet people saw that coming when they started using cell phones. (The Roadster probably wouldn’t be for me - that is like getting the deadly combo - the sun and EM radiation, a head-to-toe toast
)
Ok, enough of that, in all seriousness, what is it gonna take to put some insulation mechanism in the car? How much does the rubber or ceramic powder cost (Ceradyne is the best company out there just in case you are interested) ? I know this could be like dealing with the Y2K situation - anyone still remember? But if the engineering team at Tesla turns around and takes the precautionary position, this could be a huge selling point for you - just a simple cost-benefit analysis. I would assume most of the Tesla owners have higher expectation in general and appreciate better things in life. In the end, can Telsa set the golden standard for the EV industry and lead the pack?
Roy: Internal combustion engines, with their high dependence on momentum, have their highest torque at high engine speed, and need reduction gears to start the vehicle moving. An electric motor’s torque curve, has its high point as the motor starts, requiring no reduction gears for starting the vehicle rolling. That’s why I suggest the all-electric power train to exploit this torque curve. If the electric motor can eventually spin the wheels at 13,000 RPM, then (Wow!). What a high speed!
Jeremy Landsman: You suggested “I suppose the motor would have to be mounted near the wheel itself, (with) power transferred via a CV joint.”
I would suggest two CV joints (one from motor to half-axle [HA]; the other from each HA’s other end to its driven wheel) not just one. This prevents that wheel/HA assembly from tucking under in hard cornering, as the early VW Beetles sometimes did, which often rolled them over.
Otherwise, you sound quite right that “the motor would have to be mounted near the wheel itself” on the suspended mass of the vehicle, but just not in the (unsuspended) wheel.
I wonder what your monster would do if it had a turbine engine fueled by instant steam to drive an electric generator?
Antonio, you forgot in your calc that you won’t have all those panels facing Sun. If it radiates directly up you have only roof to collect radiation, if it is low in horizon only one side is collecting radiation assuming you car is faced 90 decree angle to sun. You can’t get same output from car surface as you would from rooftop.
Also that is expensive. Doing usual car paint job isn’t cheap, and if you have solar panels in it it would be several times higher.
80W is quite low conversion BTW. I calculated using two square meters as my base figure and got that 200W. Using your figure I would get only 160W with perfect conditions.
i agree that if prices go down and efficiency goes up they are more that just curiosity (there is nanoantennae invention that can convert up to 80% of sun radiation to electricity which means 800W / m^2 in perfect condition). Until then I think they are waste of time and effort. Maybe you could get roof with solar panels if you pay enough, but don’t expect it to affect much.
calactic cannibal, I’m a man. My name comes from Bible: “Timotheus”, even that I’m not religious nor are my parents. I’m not working for Tesla, I’m just fan of the car and the consept.
Raye, Roadster does have insulation. Your worry for nothing there. Everywhere you go you get EM radiation. From Sun, from computer next to you and from monitor in front of you, from your laptop, or your neighbor laptop, cars and metro and trams, aeroplane induction etc. etc. You just can’t avoid it. Roadster engine magnetic field is way too low power to cause anything.
Hi Timo,
For me, 4.2 miles charge a day is not so bad even if it appear “nothing”. My way from home to the station is 4 miles.
I’ve on good day the half of my way paid…
Seriously, a solar panel can also be used to avoid the battery to give power to cabin lights, 12v adaptor or just air blow system non? Even if this is not full power to them it can be a free parts. A CIS roof film of 1m² whould how much? Less than 800$. If you buy an electric car for her green side, if you can buy a car of 99.999$ maybe you are not at 800$ near…
No?
First let the way open then see how people react to them.
Maybe here, in Europe, do we think a way different as in the US?
Talking about solar panles, my house is already packed with 36 Cis module, delivering a peak 2700Kw.
Actually, after 8 month of exploitation i’am at a very good (better than previewed) 2400Kw produced.
In one year, considering the arrival of autumn and winter, will i generate approx 3000Kw.
If such panels can give so good efficiency with not on a car?
(sorry for my english which is not percfect at all)
Xavier
David,
Power is torque times rpm. Tesla has optomized the power to peak around 75 mph. Torque remains linear up to the point where the voltage becomes a limitation, and then falls off. Peak power is usually just after this point (about 8000 rpm for the Tesla) . After this crossover point the horsepower remains almost constant as torque * speed stays the same. In order for Tesla to use the full power capability of the motor, they must use a transmission (about 8.2:1). Without this the top speed would actually be slower because the wind and rolling resistance would overcome the available power before the peak power was achieved. A consequence of having the transmission is that the torque is mulitplied. Therefor there is much more torque at the wheels than there is at the motor. This high torque at the wheels makes it possible for Tesla to achieve their 4 second 0-60mph time.
Just to add an exemple to this look at the Renault Fluenz E-Z concept which use photovoltaïc cells to help the battery in giving power to the climatisation and other electronic on board.
Another nice point we can mention, in an other part, is the heat pump installed by Audi on the E-tron instead of a classic cooling system. Every things which can help to gain power and co2 must be analysed. If all this technologies, if affordable, are installed in the same car it can give huge result. Tesla have a lot of advance looking the other manufacturer. I hope they can hold the lead by learning from other presentation in the world.
xavier, don’t you mean watt, not kilowatt? 2700kW peak sounds like a solar power plant to me.
Of course you get _something_ from solar panels fitted in the car. It just wont be much. Generally it is not worth the cost. Because you already have solar panels in your home it would be wiser to plant those panels there instead. More efficient and less costly. You would get many miles more from that arrangement.
I think Tesla Motors has done an excellent job engineering a great car, but the single thing that makes the product impractical for me is battery longevity. It is reasonable to expect consumers to pay $100K for a technologically advanced performance car, and I don’t expect to reach 100000mi anytime soon, nor have problems with the more than adequate range, but a five-year life expectancy for a major cost part replacement is personally not acceptable. If I buy a high-quality, expensive vehicle today, I have the reasonable expectation that it will last 20 years with basic maintenance - that has been my experience. The electric car will be truly tempting once it offers not only great driving performance, but also a battery that lasts at least 10 years and costs less than $10K to replace.
And now a word from Journal of Power Sources:
A recent article (accepted 12 June 2009) discussing about Silicon-carbon composite anodes lists full battery capacity of 400+Wh/kg with 0.13% loss in cycle capability. Roadster 300kg battery would then have 120kWh capacity which is 2.3 times more than it has currently. That translates to 563miles. At 100000 miles it has been cycled 177 times. That means it would still have 447 miles left in the battery capacity.
There is another article talking about using high voltage spinel cathode which also mention 100-126+mAh/g capacity with 3-4.9 voltage range (300-588Wh/kg depending of how much current we draw out of it) for full batteries with over 95% capacity retention over 50 cycles. If we take same 400Wh/kg battery we get roughly 475-500 miles left after 100000 miles assuming loss is linear (which it probably isn’t, but does it increase or decrease, article doesn’t say).
Anyway all of these recent articles seem to have at least 400-700Wh/kg capacities with 400-500Wh/kg tested on full batteries and with high cycleability and power. Not with single tech, but with multitude of different techs seem to get to same range of capability. There are also *HUGE* capacities mentioned in other techs (up to 2-3kWh/kg), but those are not tested with full battery and are more theoretical than practical.
Anyway, looks promising for me.
The experience that I am having with my Roadster agrees with all of your data, except the WH/mi at 60 mph. The chart shows 250 WH/mi while my read-out consistantly shows 206 WH/mi.
Then, after you are promising to be so good, why do not organize a race?
Japanese, European and American EVs together.
The race would be more profitable for participants than Formula 1.
Alan, that 206 Wh/mi should give you 250+ mile range at highway speeds (assuming 52kWh battery). Have you tested can you go that far? Looks good. I hope that doesn’t mean Roadster has inaccurate speedometer which shows less speed than you are actually going. Can you test that (in here there is every now and then automatic radar next to highway that shows you how fast you are going. Very good at checking if your real speed and measured speeds are same).
Alan;
Not tea bags! That’s a 21% increase in efficiency and range, and would get you about 250 miles at a steady 60mph. Are you using any accessories while getting that reading?
Any updates for this blog? This JB Straubel efficiency-blog has been here now nearly ten months.
We want something. Updates for Type S progression would be nice. Measured energy losses using whatever drivetrain prototypes use (I assume it is same as Roadster). Add some weight and measure again (one passenger, four passengers, five passengers and trunk full of stuff). Aerodynamic losses especially are my interest. Type S looks much more slippery than Roadster, so I guess it might have same or less aerodynamic resistance even that it is bigger car. Any news on there “experimental batteries” I heard are used in Type S. Specs? And so on and so on…
I know all of you are busy doing something else but visit here every now and then would be nice.
Timo,
Effectively, peak power is 2700 W/C not KW (misstyped).
I think at this moment that everything we can do to be clean must be done. It’s with all the small things together that we can achieve big one.
Next Wednesday is arriving the first Tesla Roadster for a test in Belgium. I already have my test booked in Brussels.
I hope i can come back with a lot of idea to exchange with you all after this test.
Dear Tech Folks:
I don’t know anything about anything, but I came across an article in Elektor Magazine recently about a Lithium-Air battery being developed at the University of St. Andrews that I thought was promising:
www.elektor.com/news/lithium-air-battery-with-enormous-capacity.1015362.lynkx
Best wishes to your team,
Dan.
In my country (Slovak republic) are EVs on zero level. But I think the future cannot be different. The efficiency of EVs is excelent. Yes, it depend also of purchase price and total costs of opperation, but my next car will be “some electric.”
Thanks for published graphs, its absolute clean way of advertisment.
And something for TESLA team : Make clean and nice cars - we are waitng…
My hat is off to Tesla and your team. I visited your showroom and it’s not an understatement to say “WOW” Again it shows the vision and courage to bring an EV into production against all odds. No gasoline engine,No Motor Oil, No Transmission, No Gas Tank, No Emission-What is there not to like. SIGN ME UP, I want to join your team
Very interesting and informative. Who do I talk to about an idea on increasing battery life?
Susan,
You are not likely to get a response from Tesla. You could just post your idea. By increasing life, I suppose you mean number of charge cycles, not range per charge. Typical Li-ion batteries are rated at about 500 cycles, Lithium manganese polymer 1000 to 2000, A123 claims their nano-phosphate battery lasts 8000 cycles. Battery life depends on many factors such as depth of charge/discharge. Tesla’s battery charge is programmable so you can select maximum charge typically 85% to 95%. GM’s Volt is set to charge to about 85% and discharge to 30% before the motor/generator kicks in. Temperature is another important factor, both Tesla and GM use water cooling. Solar cells on the roof are not worth the extra cost. I hope you are not thinking of crazy schemes like using an alternator to charge the battery while driving. We should know if EEStor is real by years’ end, it is good for a million cycles. There are other exciting high energy density batteries in research that may be on the market in 5 years or so. My current favorite is a new Lithium-Sulfer battery by Dr. Linda Nazar www.greencarcongress.com/2009/05/researchers-develop-electrode-materials-for-highcapacity-lis-battery-cells.html#more
There are several past blogs about Tesla’s batteries, look in left hand column, one is “Smarter Charge”
Susan, “Smarter Charging” is a poor example. Better examples are: “A Bit About Batteries” www.teslamotors.com/blog2/?p=39 and “The Most Coddled Automotive Battery Ever?” www.teslamotors.com/blog4/?p=59#more-59
The limited range of electric vehicles is still the biggest drawback for them. The 200-300 mile range of the Tesla vehicles is very impressive, especially compared to the 50 mile ranges the other car companies are bragging about. (how come the major car companies are only able to go 50 miles using only electric ?!?!?!) However, a 300 mile range is still not adequate for someone, or a family, when on a trip.
I’m wondering why someone has not developed a hybrid that uses hydrogen fuel cells as the other half of the hybrid, instead of a gasoline engine. Couldn’t a hydrogen fuel cell work just as well as a gasoline engine in either charging the battery or directly operating the motor of an EV?!??! Do we really need to have hybrids that still depend upon using gasoline engines?!?!
Does Tesla have any plans to develop a state-of-the-art hybrid that doesn’t use a gasoline engine?!?!?
Hey can you glue some of those Konarka power plastic strips on it ?
GR: problem with hydrogen fuel cell is that you don’t have hydrogen accessible anywhere. At least I don’t know any refill points for hydrogen fuel cells.
It is also polluting tech, many times worse than ICE -engine, at least until we have all power plants transformed to green energy sources. You need to use power in order to generate hydrogen and that process has poor efficiency currently. The “long tailpipe” is very much true for hydrogen fuel cells.
Fuel cells also have pretty poor energy and power densities, so just adding more and better batteries and charging them whenever you can makes more sense. Electricity is available pretty much everywhere. Breakpoint for BEV to really become common car is about 600mile range with reasonable price. With current battery tech advance rate it wont take long for that to happen.
I remember seeing an article that describe hydrogen ‘filling stations’ that used solar power to separate the hydrogen from water… I believe they were in California… whatever… I’m really just wanting to see something besides a gasoline engine to show up in a hybrid…
But yes, the REAL solution will come when affordable, and especially cheap, batteries are developed that are truly practical in filling all the needs of a typical driver. The 600 mile breakpoint should be considered a minimum, unless the car could be recharged quickly enough to continue driving. I’m saying this based on my own personal needs. I drive once or twice a year from Austin Texas to Louisville Kentucky to visit family. It is a 1000 mile trip, which is just about the maximum distance a heathy person can drive in a day. So for my needs, I would have to have a car that could travel that distance at highway speeds, while headlights, GPS, and air conditioning or heating (and radar detector ;>) being used.
Now I can make the trip in my Corvette with only 2 stops for fuel. Which works out just fine, since that also allows for picking up a bag of burgers a couple of times as well as nature breaks. So actually a 350 mile range would be sufficient, if the facilities were available for fully recharging the car in 15 miinutes or so. So maybe advancements in the charging technology alone could solve the ‘problem’.
Sometimes on these trips, It can be a problem finding a gas statin that is open, right at the time I need to refuel. The same would be possibly true for finding a charging station right when one needed it. In an ‘ideal’ world, the ‘real’ solution would be a 1000 battery range at highway speeds, eliminating the recharging part of the equation. Maybe part of that can be in the advancment of solar cell technology or generators around the rear axles that could provide charging while driving… I know those technologies are not up to the task now, but maybe in future…. However, all of those kinds of ‘add-ons’ will disappear anyway, once the batteries themselves are up to the task.
I do still laugh whenever I see a 40 or 50 mile electric range being mentioned in the specs for the electric hybrids that all the major car companies are announcing and developing now… ha!!! Wouldn’t it make more sense for all of that development money and manpower to be spent working with Tesla to further develop the superior technology they have already demonstrated is possible?!??! Get rid of the gasoline engines completely!!! Is it money and power of a gasoline lobby or the oil companies that is keeping that from happening?!?!
GR,
Hydrogen fuel cell cars ARE electric. They have a small battery to aid acceleration and capture re-gen from braking, and drive electric motors. Although FC range is a little better than batteries (max about 400 miles) it is still limited compared to gasoline. As Timo pointed out, they are less efficient than pure electric. Honda has already brought out the first FC car on the market and others will follow from Mercedes-Benz and GM. I think it is wise of Tesla not to compete directly with the major manufacturers in terms of hybrids or FC’s. Fuel Cell cars and hybrids are much more complicated than BEVs and for Tesla who does not already have vested manufacturing in ICEs or FCs, it would be a major effort. And why bother when BEVs are the winning strategy anyway?
Roy, I read from somewhere that Honda is abandoning FC cars in favor of BEV just because BEV makes more sense. I think that Mercedes-Benz (Daimler) with this new contract with Tesla would be also making BEV instead of FCV.
Honda FCX Clarity has only 240mile range before it needs refueling.
I’d like to revise an earlier blog of mine:
On September 1st, 2009, I mentioned that: “wheels are temporarily turning at differing rates, (with) one wheel (the shorter-radiused, inner, and therefore slowest one) (providing) the power while the (other 3) coast.”.
I’ve thought of a weakness it has: to move the car through the inside of curves/corners, only one wheel powers the car. Each individual motor would really need enough power for the whole vehicle, as I had described the system, not 1/3 that power, as I originally said.
There is a way out of this: To begin with, the vehicle could be built with four-wheel steering, as GM pickup trucks had, a few years ago, with their so-called “QuadraTrack”. Assuming a 4 wheeled vehicle, that would allow both non-leading wheels to track directly behind the wheel ahead, giving each the same turning radius. As they do, both of each side’s wheels turn at the same speed, deploying 2 wheels, instead of only one, for power on that inside track. Now, with two wheels sharing that duty, both inside-track wheels carrying the same load, and only the outside track’s wheels coasting,only half as much power per wheel is needed, allowing smaller motors. It still needs no differential, transmission, or front-to-rear drive shaft. Its power train can still be all-electric, with only one control system for all 4 motors together.
Or 4 separate control systems could be used instead of the 4-wheel steering, etc. avoiding one system’s extra expense for the other’s, if the four-wheel steering would add even more expense.
GR, do you speak of 1000mile round trip or one way trip? If it is round trip, then 600 mile range would be quite sufficient. If not, then you would need to charge one time during your trip and once at back home (and for both cases once at destination).
Charging 600 mile worth fast is not that simple task because of physical limitations. There are real issues that prevents to use enormous amps unless you use superconductors. Also battery itself slows things down. Current realistic “fast charge” is about 5 min charge.
Thing is that for 600 miles you need to use about 170kWh battery. To charge it in five minutes you would need 2040kW connection. That’s over 2 Megawatts. If you charge system is 95% efficient you are heating things up at 107kW power. That’s a lot of heat to dissipate. For 15 min it still is a lot. Also required amps and volts are huge. For about 1000V system you would still need over 2000amps to do that 5 min charging. Not a small cable.
Battery swap system would allow relatively fast method of “charging” but realistic “fits to all” system does not exist and I don’t think will ever do (just too few customers for it to be profitable).
Problem with hybrids with high pure electric range is the weight and size-requirements for battery as well as control unit size combined with weight and size of the other system. Using two different systems increases complexity of the system as well as weight quite a bit which affects car performance. For FC it isn’t that bad because they already are FC/BEV hybrids. Maybe in future we could have long-range FC/BEV hybrids and shorter (600mile) range pure BEV.
I just stumbled upon popular mechanics site where Mythbusters show why BEV beats ICE.
WARNING! can contain spoilers about Mythbuster episode, so don’t read if you dont want to get spoiled.
www.popularmechanics.com/technology/transportation/4264025.html?series=19
WARNING! can contain spoilers about Mythbuster episode, so don’t read if you dont want to get spoiled.
Pretty funny article.
I’d like to revise my September 1, 2009 blog, that concerned electric cars supported by center-silled frames, with four, mechanically independent, wheel-motors attached to that center sill (not in hubs):
I mentioned that: when cornering, or on curves, “wheels are temporarily turning at differing rates, (with) one wheel … “, the shorter-radiused, inner trailing, and therefore slowest one, providing all the torque to accelerate or even just maintain speed, ” … while the (other 3) coast.”.
Yes, using four separate, but electronically coordinated, control systems could keep all wheels delivering enough torque to supply power instead of coasting, but would add some expense.
All the above assumes only one pair of wheels steers though. Assuming a four wheeled vehicle, one alternative might be four-wheel steering, as GM pickup trucks had, a few years ago, with their so-called “QuadraTrack”. That would allow both non-leading wheels to track directly behind the wheel ahead, giving each the same turning radius. As they do, both of each side’s wheels turn at the same speed, deploying 2 wheels, instead of only one, for power on that inside track.
Now, with two wheels sharing that duty, both inside-track wheels carrying the same load, and only the outside track’s wheels coasting, only half as much torque per wheel is needed, allowing smaller motors. It still needs no differential, transmission, or front-to-rear drive shaft. Its power train can still be all-electric, with only one control system for all 4 motors together.
Since four-wheeled steering is an already developed concept, would it cost more than four separate control systems– more than motors with twice the torque?
Finally a new car projects that is incredibly interesting and stands out! I have little concerns about the technical aspects since most manufacturers come with great technical capacities and features to new products.
But I must admit I am slightly disappointed with the design… It looks like a Chinese cheap copy of a ‘real’ sportscar. Must you really make it that cheap? The front looks like a mushed in dorky smart car for geriatrics. Its a bit too short. Lights are positioned too close to the windshield and adds a nerdy look. With the roof on it gets even worse. You at least lost me right away as a buyer.
Is it really necessary to ruin a car this way when you now have the chance to do something awesome and perfect? The back is fairly OK but could do with some remodeling too. So many car makers ruin their designs and then wonder why their popularity is short lived.
I guess the reason why Ferrari (the new California, gorgeous; every curve is a masterpiece), BMW, MB (2 seater AMG), Bentley, Aston Martin, etc are some of the few brands that keep on top year after year; they finetune their designs. Even riceburners like Honda managed to make a handsome car with their Cab S2000 although a bit too small and unpractical.
And why a 2 seater that fits nothing but a grocery bag? Just extend it a bit and allow backseats - and you immediately open the market to twice as many buyers. Backseats doesn’t have to mean making the car look like its meant for old people. I am still waiting for MB to just extend their SL 63 AMG and add backseats to it. At least 3/4 of a backseat is better than none. People who love cabs would die for a great cab with 4 seats. Unfortunately, no one makes them and tend to ruin the design as soon as backseats are added. If adding backseats become too heavy, at least try and do something about that unattractive front end!
Timo, to increase the range from 300 to 400 miles would mean increasing the range by 25%. The charts above shows a speed of about 55 mph for the 244 mile EPA rated speed on the Roadster (note the official EPA range rating was made using a “drive cycle” with varying speeds). To increase that by 25% to 300 miles would mean driving about 45 mph.
If the Model S has a similar efficiency curve, (thats a big “If”) then a rough estimate to get a 400 mile (644 Km) would also mean travelling at about 45 mph (72 Kmph). That might give you the range you need with a substantial safety margin. Of course, if you could take 1 or 2 rest breaks along the way and get a partial recharge, you’d be able to drive a bit faster than that! I’m hoping that lots of public recharging outlets will be available soon along major highways.
marco g. carle: Tesla Motors has started accepting online orders for Europe, but with a substantial backlog, it will take awhile before deliveries can be made. One drawback is that the nearest Tesla stores are in Munich and Monaco, a long ways to go for service. Tesla Motors will be opening many more stores as fast as finances permit, so eventually there will be Tesla stores in Italy.
GR,
You highlight the situation for which EVs are not (yet) well suited.
If you make that drive “once or twice a year,” how far do you drive on the other 300+ days? Chances are that it’s under 200 miles. So we need to question whether it makes sense to engineer a car to make the twice-a-year trip and make it carry around the extra cost and weight the rest of the year on the short trips. Just like you might rent a flatbed truck from Home Depot once a year to haul a big load of lawn mulch, rent a car for the 1000 mile drive and enjoy the benefits of electrics doing what they’re good at the rest of the year. If I owned a flatbed truck , I wouldn’t be very happy driving it 1000 miles to Louisville in a day either - I’d probably rent a Corvette for the trip. Pick the right tool for the job.
Of course, in 30 years, electrics will be the best choice for everything.
Ann, I think beauty is in the eye of the beholder in this case. I rather like the design of the Roadster (except with the hardtop, in that part you are quite correct. softtop is quite nice). Roadster design is pretty close to Lotus Exige, and as such is made for agility, not speed. Short car with weight in the center means agile car.
Tesla does not have very good pictures about Roadster. Or Type S for that matter. There is one blogger Bill Arnett that has much better pictures. Whoever is taking promotional pictures about Tesla cars could use some advices from him. bill.nineplanets.org/Tesla/Yosemite1/index.html. Some of the videos and non-Tesla pictures I have seen show that those cars are in reality very nice.
However I like Type S design much more than Roadster. I have no use for two-seater toy car, no matter how “cool” it is. I need backseats and decent trunk too. For practicality Type S is way better than Roadster.
Roadster is like “hmmm… nice looking car”. Type S is like “drool…Want one! Give me my car now!”
BillB, GR,
One solution may be, and i think many people will find that interresting, the possibiliti to connect an additional battery package for long run. Think at the Tesla S. Imagine you have a 400 miles range, you know you have to make the way longer, think twice at the bagagery and connect you additional 400 miles battery pack (think more: a rentable battery pack at the Tesla store in town!) and you are gone.
Renault think about that… why not here. A store where you can connect an additional pak, and not as renault a complete set, so you everytime energy for “local” drive and possiblities for long drive. Having stores in distant country will be then a great point.
You are at the hotel, knowing that you go back to home in 3 days… UPS or FedEx bring you your additional battery pack, you pay with VISA for the rent and warranty and you can go home.
At home, you send back the battery pak to the stores, you receive your money back for the warranty.
This could be very very helpfull in many case. We everytime hear about “it’s too short”, we can answer “no more!”
How about combining the 4-motored electric car’s platform with a carbon fiber body. Boy! Would that ever be able to take on battery weight (without losing strength – even compromising some body weight savings for more strength than similarly dimensioned steel body without reaching a steel version’s weight).
That would increase range, at any given average speed and battery technology!
Over the last few month I have been reading what people are saying, but no one has put there views into practice. A lot of talk about batters and what could be done, but I have not read where someone has tried it first before writting about what the company could or should do, I am very intrested in EV, so what I have done, to add a plus to my story is I went and
brought an Electric 1500w hub motor scooter as a test bed with 4 X 50ah lead batteries with a top speed of 46kph and a full charge range of 55-60km. This a 48v system with max draw 25amps, plus been a very heavy unit. I have change the hub motor for 1000w high performace motor, through out the weight (lead batteries) replace with 1 pack of 16 = 48 x 3 of LiFePO4 batteries = half the weight of the lead batteries. perforance, top speed 92kph, range 200-230km on one charge.
If I can do this, why has some of the writer above, done some mini trial to see how there ideas would work?
If you wont to see how the good DC motors can be with minium use of battery power, look up CSRIO in Australia and see how they are getting 98% out of there motors.
Rei, can you tell us (me) more about your eScooter. How much space did that battery pack take? How much it weights? What kind of scooter? How did you calc that 200-230km range?
I’m not engineer and I don’t have space or time to tinker with that sort of things right now but my vision was to build tiny cheap runabout, maybe based on ATV: something like this: www.ecoeatv.com/products/e-force-atv/ but less off-road (smaller and less friction tires for example) and more like a car to make grocery shopping. If I add two hub-motors and those batteries to lightweight ATV how far would you think it could go? That link ATV has usual lead-acid batteries (6 x 12V-50AH SLA AGM). Where did you get your batteries and how much did they cost?
I’m also a bit confused about your engine change: from 1500W to 1000W system. That should net out lesser performance, not greater.
Just read from news that there is new high energy density lithium-ion battery factory being build in Finland. They are making those batteries for industry and EV:s. www.europeanbatteries.com/news
Tried to dig out _how_ high energy density batteries they will make, but there is no info. At least not yet. Apparently they will be producing large format prismatic lithium iron phosphate batteries. That’s pretty much all info I could find. That can mean anything between 200Wh/kg and 700Wh/kg, so not much use for that info.
It’s nice to see that industry is slowly realizing that BEV is the automotive future.
How would you like to extend the range of your vehicle to unlimited? Generators, capacitors and voltage regulators in conjunction can accomplish this. I approached Ford and Chrysler with this idea and the response ( from a technician)
suggested that it was not possible. I assure you it is. Lew Chandler.
I have an idea for “charging”. Installing a small wind turbined and a generator in the front bumper. Funneling the air that comes though the front bumper would spin a small turbined that spins a generator, which would charge your Li-ion cells. I think merging both technologies would make the electric car a clear winner in alternative fuels.
Everything I have read on the Tesla Roadster is very impressive except the concept of the two speed transmission that could not stand up to the torque, and had to be locked into 2sd gear. I haven’t read anywhere that I could find where a CVT transmission was tried. CVT’s were introduced years ago, and are not in several different vehicles such as the Nissan Maxima. Are there any articles or trials using some type of CVT for better response, or is the extra loss just that more motion loss within the transmission to drain the batteries.
Thanks
Not again perpetual machine inventors.
lewis chandler and Mike Olsen:
Energy from car movement comes from electric engine, it is not free energy. Installing generator to electric engine slows engine down as much as generator creates energy + energy losses. Same with those wind turbines, they increase wind resistance equal amount of the electricity generated and then some, which means *YOU BOTH* are suggesting lesser range. In optimal case you would get zero, zilch, null, 0, increase in range.
Try it. Attach generator to engine and then give it a spin to start it. If you are correct then that combination should cause electric engine to accelerate.
Joey Simon, Roadster has now single gear, not second gear locked, but simply one gear. That’s enough to give it 0-60 in less than four second acceleration and 125mph top speed. There simply is no need for any transmission.
lewis chandler: What powers your “generator”? If it is a gasoline engine, then you’d have some sort of plug-in hybrid. GM is using that approach for their upcoming Volt, but Tesla Motors decided to go “pure electric” instead. If the generator is powered by the wheels, then you have regenerative braking, which Tesla is already using. Great for recovering energy while slowing down, but of no use when cruising or speeding up, and it won’t give “unlimited range”. Your “idea” sounds suspiciously like an “overunity device”, but I’m betting you haven’t actually built a working model. Engineers don’t believe that “overunity devices” work, and the only way you’ll ever get them to listen is to build a fully functional model that they can test. Sorry to say, I suspect the Ford and Chrysler engineers may be right and you’ve overlooked someting that prevents your idea from working.
Mike Olsen: You aren’t the first to suggest a wind turbine on the car, more like the 101st. Sorry to tell you this, but you’ve over-estimated the amount of power a small wind turbine can produce, and under-estimated the aerodynamic drag it will produce. The energy loss to that drag is about twice the energy the wind turbine can produce.
Joey Simon: Tesla Motors solved the “transmission problem” over a year ago, by using a simple single gear transmission and adjusting the voltage to boost torque at low speeds. A CVT would add unnecessary weight and cost. Tesla has already put the new solution into production and has delivered over 700 Roadsters to happy clients.
CM;
I think I first read that 700 delivered a couple of months ago. (?) What’s the current #, do you know? Like many here, I’d love to see a real-time moving bar of the total sales and/or deliveries on this site. Oh, well.
Battery technology will need to advance for BEV to become really ace. Also, If you could make the frame (the heaviest part of the care) be the battery, now there’s an idea, two birds with one stone.
Also, I thought this was interesting: a novel approach to “storing”electricity in aluminum. Basically a better battery. The thing that would keep this from happening is the completely and hugely different infrastructure. But it’s cool/
hydrogen.ecn.purdue.edu/2005.10.28-Woodall/
Range Extension:
It seems to me that if the maximum changing rate is 16.8 kwh, and if the maximum discharge rate of a new 100% charge battery is 55 kwh, that the maximum mathematical range extended device would only add ~30% to the range given all variables are equal and the load minus converter losses is greater than 55 kwh draw from the new battery. Is this a safe assumptions of the limitations of the current arrangement?
Thanks,
Jacob
Bravo! Tesla motors is an automotive revolution. Has anyone thought of installing solar cells on the roof of the vehicle?
Jacob, I don’t quite understand what you are saying.
If you say that maximum charging rate is 16.8kW then you get infinite range with infinite kWh battery with speed/acceleration that uses less than 16.8kW. Maximum discharge energy from battery is 55kWh, but with range extender energy would obviously be more than that. Maximum discharge rate power is obviously a lot more (about 200kW), and so is also maximum charge power, but that just is not used in usual charging.
Brian H: I don’t know the current total of deliveries, I only find out when there is an announcement from Tesla.
Jacob: The 16.8 Kilowatt rate is the power limit a 240 volt 70 amp electric outlet can provide, it isn’t the charge rate limit of the battery pack itself. But as far as any “range extender” is concerned, it is irrelevant, as the main function of a range extender is to take over the electrical load from the battery pack, not to recharge the battery, and it would partially recharge the battery ony if there was surplus power available. The only limit to a range extender would be set by its fuel supply. BTW, “Kilowatt” is a measurement of power, and “kilowatt-hour” is a measurement of energy, that is, power over a time interval. The total Energy the Roadster battery stores is 53 Kilowatt-hours, but the peak power output of that battery is over 185 Kilowatts!
Jerry Psimer: The cost of solar cells is high, and the power produced is low, especially if shaded or angled away from the sun. Attaching solar cells to the car would add thousands to the cost, but would add less than 5 miles of driving range per day. Tesla Motors didn’t consider it worth the additional cost. That could change if costs drop or power output improves.
Battery changing:
Just made some calculations based on my sisters yearly driving (thinking I could buy her a Roadster). Based on that she would save about 12000$ in fuels in five year period. Then noticed that Tesla is offering battery replacement for 10000€ in seven years. For seven years savings would be 12000€. Looking good this far.
Problem is that by that time she had driven battery pack to unusable condition. She drives easily over 25000km / year which is over 15000 miles / year. In seven years that is over 110000 miles. If battery contains only 70% of its capacity after 50000 miles (based on FAQ) then that would approximate 40% or less capacity after seven years. That’s not enough.
Spec sheet says “Battery Replacement (price based on battery replacement 7 years after delivery of your Roadster.
Pro-rated rates available for Battery Replacement before or beyond 7 years.)” What are those “Pro-rates”?
Hi.
I always wondered how efficient are the petrol generators. They are basically ICE engines hooked to a generator to create electricity. Looking at new Peugeot’s diesel engines they achieve astonishing 70 mpg (probably driven at 55)
that is about 15kw power needed to push the car so the ICE must be able to produce at least 15kw for 70mpg at 55 = about 19 KWh/galon
given the 54 KWh battery at the Tesla this means recharging it in 3h (including the losses probably)
Now take note that the diesel engine I am quoting is 2liter. However if you make it smaller (as 15kw is not much power - about 20 hp) probably under 1l very compact engine can produce such power at similar rates. May be even more economical.
Would it be feasible if such generator is made mountable/portable so you mount it in the trunk or something when you go on a long trip. At 55 the tesla is going to do 70 mpg using that ICE to produce the electricity and you wont have to stop, unless you drive over 65.
Given that you will need that ICE probably 1-2 times a year it can be made even rentable.
The thing is , how cheap/small they can make such device and how hard is to make it mountable/portable
I guess if it weights 200 pounds its not mountable/portable. Probably 50-60 pounds at most can be considered portable
autospeed.com/cms/title_Little-Diesels/A_109062/article.html
I think its feasible to produce a 10-15 KW diesel engine using cutting edge technologies and make it so small to be portable.
you can probably leave heat decipation and other items needed , at the car all time, and make only the actual engine block removable, (fuel pumps, reservoir and stuff can also stay at the car at all time as they would be small).
Anyone have any ideas or reasons if this is impossible - why?
Finally I found some reference !!!!
www.fram.nl/workshop/engine/smartengine.htm
Weight = engine + gearbox + marine gear = 65 + 14 + 22 = 101 kg. (223 lb)
So the actual engine is 65kg!!!!!!!! wow
an 300-400 cubic engine will be able to produce the needed 15-20 kw of power and I bet it will be probably under 35kg.
Why havent anyone already thought of that. Electric cars are super efficient and we can use that.
Just saw a press release yesterday saying deliveries were “nearing” 900, so I guess that’s as current as it gets.
Jet;
That aluminum technology is a multi-step affair. Store pure aluminum in a protective solution with gallium, then add water which is broken down by aluminum’s aggressive affinity for oxygen, releasing the hyrdrogen, which is then run through a fuel cell which generates the electricity, which would have to be “buffered” in some kind of instantly variable storage to allow for acceleration, etc.
Its storage capacity is large, though, so it might see the light of day.
But it wouldn’t be using the aluminum frame as its metal source! The metal has to be added in small pieces or powder to the solution, or provided in solidified Ga-Al-Si(?) solution form. When exhausted, the residue is a mass of fluffy alumina “foamed” solid on top of the mixture, which must/can be removed for repurification. Which is where the electricity cost comes in, because that’s a very power-intensive step.
Typo: hydrogen, not “hyrdrogen”.
ops:
RawSteel, That engine is 0.8 litre or roughly 50 cid. How do you figure increasing displacement about 8 times results in half the weight? I think you meant 30 to 40 cubic inch engine. For high power to weight/size look at Freedom Motors www.freedom-motors.com/
Finally a new car projects that is incredibly interesting and stands out! I have little concerns about the technical aspects since most manufacturers come with great technical capacities and features to new products.
But I must admit I am slightly disappointed with the design… It looks like a Chinese cheap copy of a ‘real’ sportscar. Must you really make it that cheap? The front looks like a mushed in dorky smart car for geriatrics. Its a bit too short. Lights are positioned too close to the windshield and adds a nerdy look. With the roof on it gets even worse. You at least lost me right away as a buyer.
Rawsteel, that kind of portable generator has been proposed before and it isn’t that bad idea. Roadster uses only about 15kW in highway speeds (much more in accelerations) so if you can produce, let say 20kW with generator and charge battery with that leftover 5kW you should be able to use battery for accelerations and still get battery slowly charged. With 5kW that would take about 10 hours, with 20kW 2.5 hours.
If not for driving and charging then smart charger + that kind of generator and stop for charging. You need also around two and a half - three gallons of diesel (if using that engine you linked) for full charge. That would be around 75mpg. Pretty nice. I bet there are better solutions than that engine that are tuned for generator use only.
BTW 65kg isn’t that small for engine less than one liter. I had one old 0.9 liter Fiat engine that engine block was light enough for me to easily carry alone, much lighter than 60kg. Of course that was not full engine it had many parts stripped out (cooling, exhaust, etc.), but it also was _old_ tech.
Full weight of the system could be somewhere around 100 kg (maybe 50kg engine, tiny gearbox for that for getting right steady RPM for generator, fuel and generator itself). You could make that portable enough for carrying it in Type S, but I think that takes too much space for Roadster.
Thanx for the valuable information. This was just the thing I was looking for, as a racing fan I will use this information well……. keep posting. Will be visiting back soon.
I hope that you could consider removable batteries that recharging station could replace. This would reduce the delay in charging the vehicles. Setting up maned recharging stations every 100 miles on the interstate that are stock with precharge batteries will bring in more customers and huge additional revenues. Just thinking outside box.
Good luck.
Anybody got the latest production count on the Roadsters? Just curious.
Just found confirmation of my first impresstion that Type S is more slippery than Roadster:
green.autoblog.com/2009/03/26/tesla-model-s-50-000-ev-sedan-seats-seven-300-mile-range-0-6/
“…and the S has a cd of about .27 vs. the Roadster’s drag coefficient of .35.”
Difference doesn’t sound much, but it is. 0.35 vs 0.27 allows Type S reach same or possibly even smaller air resistance as Roadster, while being quite a lot bigger car. That means that larger losses are result of bigger weight (mass, inertia, whatever) , and in steady highway speed only rolling resistance which is bigger in bigger car causes Type S to lose to Roadster in Wh/mile comparison. All other resistances should be about same. This also means that Type S assumed 300 mile range with 85kWh pack could actually be larger than that in steady highway speed. 85 vs 54 kWh is over 150% bigger battery pack and 300 vs 244 miles is only about 120% bigger range.
Have this been tested in any way? Using Type S prototype and some extra weight simulating extra battery weight and Roadster drivetrain?
We (or at least I) would like to hear progress information about Type S like we had for Roadster. Range achieved, battery chemistry used etc.
Timo,
Rather than a 20kW generator, I suggest having a 10kW one. If you start out with a full battery charge, and it takes 15kW to drive at highway speeds, then a 10kW generator running all the time would reduce the battery drain to 5kW, and yield a total of 10 hours of driving (= 500+ miles). Stopping for an hour for lunch (with the generator still running) would add back 10kWh to the battery (another 2 hours of driving).
This could be an extremely efficient engine (or gas turbine). It only needs to run at one speed, with no worries about the torque curve.
For most typical driving trips, a 5kW (or so) generator would probably be adequate. On a typical drive with normal stops, 5kW would give you well over a 400 mile range.
Bill
RawSteel, your idea of a removable “range extender” engine and generator is technically possible, but it does have some formidable engineering challenges and might not be practical. The range extender unit would have to be powerful enough to take most of the load from the batteries and contain engine, generator, cooling system and fuel tank, yet compact and light enough to be easily removed and installed (some sort of hoist would be useful). For safety sake, it would need to properly vent the engine exhaust, have reliable electrical connections to the car, avoid overheating the fuel tank, and safely contain the fuel in case of an accident.
It doesn’t make sense to remove the engine but leave the cooling system and fuel tanks in the car - you would have to disconnect fuel lines and coolant lines (unless air cooled), with the potential of spills and leaks, and as you pointed out, they are small, so why not keep them together as one unit.
The minor advantage in EV performance that would result from removing the weight of the range extender and extra range from installing it might not be worth the hassle of removing and installing the range extender. It might be more practical (though less elegant) to mount the range extender in a trailer towed behind the car, or just have it permenantly mounted in the car.
Or we could just use more battery capacity for greater driving range, and quick charging during rest stops for those long trips. That is the Tesla Motors plan.
What I would like to know is the real world cost of operation ? One power costs to charge it per mile, Two cost of parts to repair one including bat…. cost and disposal fee Etc. . Most people I don’t think have a clue where the power they use comes from Coal, Hydro,Nuk,Etc., if we were using water to make all our electricity (which is the cheapest energy available) this would be a good thing but more electric cars need more power in the grid and we are right now pretty tight in the wires on the ground. that mean more transmision lines (oh people will be happy about that ) and more power generating capacity. Wind and solar if we double it in five years, at >1 percent now on the grid, that will make it 2 percent , still not much on the grid from alts.,and all the political hype is all bs and lots people are making money selling the global warming bs. dont get me wrong I beleive we shouldnt be wasting things energy included, I have some bad news for people in that area because things have been changing on this planet long before man got oil and coal out of the ground. If these people selling it are so into beleiving it they wouldnt be (jet setting) all over the planet and using more energy then the average person does ( pretty (Hypocratic) in my opinion) . Anyway you people tell me where the juice is going come from ,Please? I like the concept but I cant see the cost per mile to be good and that is the bottom line !
Steve,
Are you suggesting that just because the payoff of lower energy costs, no pollution and no dependence on foreign oil is still several years off in the future, that we shouldn’t start?
The power to recharge my Roadster costs about $6 for a standard charge and I get about 200 miles, so that’s about 3 cents per mile. That’s the cost from the utility, but about half my power comes from the solar panels on my roof. The sunshine is free, and the panels are already paid for.
Yes, the climate on Earth is always changing. Before we started burning fossil fuels in large quantities, the Earth was on a slow cooling trend that would have put us into another ice age in about 20,000 years. That trend was discovered in the 70’s and a scientific paper was written about it. The popular media then took that and hyped the heck out of it, telling people we had “global cooling”, while conveniently forgetting to mention the 20,000 year time frame! That’s why you don’t want to get your science knowledge from Newsweek!
In only 200 years, we have completely reversed that gradual climate change and put the world on a sharply increasing temperature trend by greatly increasing the CO2 and other greenhouse gasses in the atmosphere.
You argument that global warming isn’t happening because people still fly on jets is laughable. It do hope you are joking.
By the way, the US spends many hundreds of billions of dollars each year importing foreign oil. Estimates for the next ten years are about $7 Trillion being drained out of our economy. If we drive electrics, that money stays here, in our economy. That’s enough cash to purchase an awful lot of clean energy generation and modernized electric grid.
I can’t wait to own my Tesla - I am planning on the family sedan model
well done
Timo/Brian H - That answers my question.
Thanks,
Jacob
Some serious competition to Tesla Roadster: www.ewolf-car.com/index_en.html#/e2
Doesn’t say price, and based on what it claims that is more a race-car than sport-car. 250km/h top speed, 0-100km/h under three seconds, 0-200 under seven seconds, 400km range. Probably also $1M price-tag.
Based on text it uses Li-tec Cerio batteries, and Li-tec has partnership with Daimler (www.li-tec.de/en/company.html) . Does that mean that Type S batteries are same as in that EWolf e2 -car? Sounds promising, OTOH I can’t find any specifics about their batteries. One of the pdf-files I found says something interesting: “developed for Formula One”. That would mean very high power density.
Inspired by Steves comment I tried to find out how much electricity (energy) is used to refine raw oil to petrol or gasoline. Can’t find that anywhere. Does anyone know how much that is? They might use excess oil for energy generation from well directly, but that does still count in the polluting factor.
Another bit of eWolf -car:
“Each flat cell (the battery has a total of 84) weighs just 1 kg and measures 23 x 18 cm. That means it is only a bit larger than an exercise book. Another important aspect of the Li-Tec battery with CERIO® flat cells is its cycle stability and unrivalled service life (10 years) and range (over 300 km). That makes Li-Tec the spearhead of current flat cell development.”
That is 84kg battery with 187mile range. Assuming same or similar efficiency as Roadster we get 244 compared to 187 = 76.5% range which would mean 54kWh * 76.5% = about 40kWh battery pack. 40kWh / 84kg is 476Wh/kg energy density. HUGE improvement over Tesla current batteries. Can’t wait to see that in Type S. And of course in 2012 Roadster. That range would be over the breakpoint of making ICE permanently obsolete (if it can be made relatively cheap by large scale manufacturing). Over 600 miles with single charge. 10 hours of driving in 60 mph average speed.
If that really is the real energy density of those batteries and they are already in production we can have electric car revolution sooner than even I expected.
I really really hope that this isn’t some overestimate hype of their batteries.
I have question to range of European version of Tesla Roadster:
Have the European version of Tesla Roadster any odher modifications which have influence to range?
Timo;
Your arithmetic is unnecessarily complex. Just do 450/84 x 187 = 967 mi. range for equivalent weight of current Tesla batteries.
Far enuf fer ya?
Li Tec is a Daimler-Evonik JV. According to the article below, Daimler holds the majority. I would assume that Tesla is very well informed indeed. I would also consider it wise for Tesla not to brag too early and loudly about future batteries, and potential suppliers - not because these may not become avaiable, but simply to not alert competitors needlessly.
www.eetimes.eu/germany/212500315
- Alfred
personally im gonna buy a tesla or at least a model s as soon as i can, but i was wondering if tesla is ever going to just sell parts, so that people could convert their old cars to be electric. and maybe they could get one of those shows on discovery where they convert a couple cars to high performance electric and then people would see that they don’t need to buy a whole new car to get the 12 -20 cents full charge or full tank price.
I have been watching your projecet sence the begining.
Good Job! I hope some day to own one of your cars.
We build houses so maybe not for a while.
Please dont stop working, someone needs to do this
dvd
Here is my 2 cents. I have seen a few comments about Charging Stations. I have another vision for them and would like to know what you think.
This is the Ramp-up System. You simply drive up the ramp which releases your discharged batteries and replaces it with a fully charged pack. The Ramp-up would hold always hold a battery pack or more. The Ramp will be available fro any consumer and also any commercial station. The commericial station version will be more sophisticated with RFID technology allowing you to charge your credit card at the same time. Imagine a charge for a charge. The inboard computer will home in on the nearest station or an individual who wants to make his ramp available for the public. Thus, any individual can be an an Access Point.
Just as the computer industry has flouished with W3C standards and IEEE standards for connectivity (protocols, ports, physical plugs etc.), electric car technology can flourishes with interchanging power packs.
To Timo - Energy
Here is an article about the energy requirement to refine petrol from crude oil
Approx. 140kW-hr (electicity and natural gas)per barrel of crude to refine 19.5 gallons of petrol
-Chad
www.evworld.com/article.cfm?storyid=1715
Brian H. I was aiming for energy density, not range. Tesla battery (not entire pack, but batteries) is only about 300kg so that would be 300/84 x 187 = 667 miles.
Of course that wolf e2 is quite a bit lighter than Roadster (because of those batteries) so it probably is also more efficient, which in turn means that range calculation I used needs some correcting factor. But I’m also quite skeptical about that range claim.
Lets make some “we don’t believe hype without proof” reduction: 187 -> 150 miles. Also increasing weight from 84 kg to 450 kg affects range….lets make some number here…(84 kg battery with casing is about 10% of e2 weight while 450 kg is from 1200+kg 37%, aerodynamics other affect some which doesn’t count here…) guessing 10% loss, which makes that 135 miles for Roadster.
That would give 300/84 x 135 = 482 miles. Roadster has 244 mile range, so that is *STILL* about twice the Roadster current battery tech.
Also if cycle life is better and battery size get doubled (kW), that is *at least* twice the durability in charge/discharge cycling.
For Alfred, even if Tesla gets those batteries, Daimler is probably first major car maker to benefit from them, not Tesla. We might get electric luxury MB:s soon to compete against Type S.
That isn’t necessarily bad thing, but it might be (for Tesla, not for general public).
If Daimler is doing this well in inventing new tech, I wonder what other not-dinosaur-infested-companies like VW is doing.
Timo.
Thanks for the link. I think E-Wolf will do well. The Li-Tec battery is a lithium-polymer design similar to Volt’s. I do not think you can assume “similar efficiency to the Roadster”. That open wheel formula-one style single-seater is bound to have much lower aerodynamic drag. It is also very light weight. I do believe li-polymer batteries are superior, but not nearly as dramitically as you suggest.
Has Tesla looked into this?
“Ionic batteries could multiply battery life by 11″
Link to article here… www.electronista.com/articles/09/11/06/metal.air.ionic.liquid.could.extend.batteries/
The article even references the Roadster.
Company link here… fluidicenergy.com/
# Chad Olivieri wrote on November 6th, 2009 at 1:58 pm
## www.evworld.com/article.cfm?storyid=1715
Fasinating. That article is a bit overoptimistic, but comments are good.
Here is another article about that that is referenced in your article (or comments about it).
blog.storybridge.org/2009/07/leave-oil-in-ground-drive-electric-with.html
From one of the comments we get this:
151,324,000,000(kWh combined electric & nat. gas equiv.)/5,119,100,000(barrels)=29.5 kwh/bbl, not 140kWh
In that same article both diesel and petrol get only 30 gallons of ICE fuel from 44 gallons of oil. That means only 68 % of that energy figure goes to produce ICE fuels. 68% out of 30kWh is 20kWh/30gallons of fuel = 0.666..kWh/gallon.
*way* less than what evvorld article claims.
Still interesting reading.
Roy, that Ewolf e2 is two-seater hard-top sportcar like …Roadster with hard top. Not open wheel and not that much lighter either (weights about 900kg which is without batteries more than Tesla Roadster would weight). From pictures it doesn’t look even as slippery as Roadster, too many sharp angles and scoops and stuff. Longer, taller and wider than Roadster (5.0 x 1.9 x 1.2 vs 3.9 x 1.8 x 1.1). It might have lower CdA than Roadster but not much lower.
E-wolf E1 is open wheel single seater that weights only about 500kg. Very different car.
Is there a plan in place for end of life of the battery cells? Are the entire units replaced or can the cells be seperatrd and then re-used? What are the recycling options?
Timo, where did you get this information?
“Each flat cell (the battery has a total of 84) weighs just 1 kg and measures 23 x 18 cm. That means it is only a bit larger than an exercise book. Another important aspect of the Li-Tec battery with CERIO® flat cells is its cycle stability and unrivalled service life (10 years) and range (over 300 km). That makes Li-Tec the spearhead of current flat cell development.”
I thought you were refering to the E1 since the E1 is listed as having a 300km range vs the E2 at 400km. Also the E1 is 500kg total with 270kg batteries. Couldn’t find battery portion of E2 with 900kg total weight.
I suspect that the E1 has 3 of these 84+kg batteries and the E2 would have 5 or 6. I say 84+kg because the 84kg is just for the cells and there has to be packaging and at least minimal BMS included in the total battery. 90kg total would be 6kg of packaging and battery management electronics. For those unfamiliar with the Batery Management System, it makes sure all the cells in the battery are equally charged during charging and prevents over charging which would destroy the cells. BMS usually includes fuses and other protective features such as shutting down on overtemperature.
Roy, 900 kg is directly from ewolf website. Same with range which is said to be over 400 km there. 300km is from another article I found …trying to find it again… hmm… there it is:
www.gizmag.com/ewolf-e2-electric-sportscar/13107/
That uses miles: 186 which translates to 297.6 km. That I then rounded to 300 km. It is also mentioned in ewolf website in performance - flashgizmo, and there “revolutionary battery technology”. (which one to believe? I think the smaller figure)
Of course this is just vision at this point, I don’t think they have even prototype build yet, so those figures can and will change.
Where did you find info about that battery total weight? I found few German pdf with mention that e1 has 180 kg battery. That sounds more like ordinary battery to me, but I can’t find any info about e2 battery weight (only figure I do find is 84kg which sounds astounding)
Timo,
E1 battery weight
www.ewolf-car.com/assets_de/presse/auto-portale/www.evworld.com.pdf
SYNOPSIS: The e.1 weighs a mere 990 lbs, 594 of which are battery and it
could point the way to the future of racing.
594 lbs = 270 kg. As I described above I believe these are 3 batteries of 90 kg each. The E1 is probably configurable with different number of batteries depending on the length of the race. That would explain your link describing the 180 kg batteries (i.e. two 90 kg batteries installed). I do not believe any of these battery options are “old technology”.
Harry Cotton:
see www.teslamotors.com/blog4/?p=66
Tesla, I’m impressed, as always. Great work. I’m still saving for a Model S!
You guys are doing everything you can. As much as I’d like to see custom kits and other suggestions such as range extention that I’ve seen in various comment threads, there are other companies doing those things, most are not very good, and it would divert too many resources and focus away from Tesla’s critical success in getting real-world, ground-up, pure EVs on the road.
Speaking of the Model S, I’d like to see some specs on the Model S - real specs, like actual EPA-based range data, 0-60 times, battery sizes and costs, etc. I’d like to see video clips of their traction control tests like they have for the Roadster. Maybe it’s too soon to discuss the pricing of options, but at least it would be neat to have the Model S, as well as the Roadster, under the various tabs, such as the “design” tab, where there are detailed pictures of the exterior and interior, as well as the ability to see what the car looks like in the various colors available. It’s already there for the Roadster.
I’m assuming that the data and options I’m asking about are available, if the Limited version is going to be rolling off the assembly line less than 2 years from today. At least, I would hope so, with such a short timeframe as well as the fact that the factory is already being built. Most of this stuff would have to have been known long before the details of the plant could be completed. I wasn’t following Tesla at all until the Roadster first rolled out of the shop in late 2008, so I don’t know how much teasing Tesla did with the Roadster specs before it was actually being produced.
One concern about the Model S, though: I hope that Tesla is sharp enough not to just put the exact same system into the Model S without the same battery (ooh, bad pun) of tests. All I can think of is France’s Ariane 5 rocket that self-destructed because one of the onboard flight control modules was never updated/calibated for the Ariane 5 (taken right from the much smaller, weaker Ariane 4). There was nothing wrong with the trajectory or speed of takeoff, but the control module thought so, and triggered the self-destruct. The Model S is bigger in every way compared to the Roadster, so the ABS brakes and traction control systems would have to be, at the very least, recalibrated and run through the full round of testing.
Also, about the Model S, is someone else manufacturing the glider? Is this plant (still being built) in CA going to make/assemble every aspect of the car?
My Toyota Scion xA is the last gasser I’ll ever own, and it will be replaced with a Model S in 2012. Ford’s Focus EV will only have half the range of the base Model S, and the other cars on the horizon, such as Nissan’s Cube EV, won’t have the same range either. That eWolf looks a bit esoteric, much more than the Roadster turned out to be. Until they come up with a more common vehicle, Tesla is still way ahead of all respectable competition. Ford and Nissan have the financial and manufacturing might to get ahead of Tesla, but that’s years down the road - Tesla got the jump on them. Now with the partnering of Daimler, Tesla will be able to match anyone in any category.
GO TESLA!!
As a companie are you looking into useing superconductor technologies in your motors to improve effeciency and power?
im just not sure why big car companies cannot replicate this. it is just a testament to tesla. why not swittch over to electricity. solar power should be the fondation for all our electrical needs.
I wonder if it would be possible and feasible to add solar paneling to the roofs windows on the Tesla Model S. The top-back and top-front window could come optional with a SEV solar panel like the Toyota Prius does, increasing mileage and decreasing recharge time and energy cost.
Maybe the technology of transparent solar panels for windows is already advanced enough as well and could even replace all windows with solar technology, which can be added as a film, like window tinting. The foil would also be UV-protective and does supposedly only cost a 10th to manufacturer then regular solar panels. They do not convert as much energy into electricity, but therefore you don’t even know it is there. When we talk about solar foil, could it not be implemented into the rest of the car chassis as well? The latest solar technology is already equivalent to fossil fuels, so maybe it is even possible to make the car almost 100% power independent. For me it could work out, I live in Florida, don’t drive too much and my car is always parked outside in the sun.
Mike Gillette: Currently, superconductivity require ultracold temperatures below -182 C or -297 F, that requires specialized cryogenic refrigeration. The energy needed to power that refrigeration is several times greater than the small amount of power saved through improved motor efficiency, it would be a big step backwards.
Now if someone develops a material that is superconductive at room temperature, then that would be of interest. Unfortunately, no one had done that, and the few that have claimed to do so turned out to be frauds.
bill,
Big car companies can make EVs, but they are generally just more interested in making gas cars. GM is treating the Volt just like they treated the EV1, it is a big PR program to show how green they are but they are dragging out introduction and have now announced that they are going to make only about 10000 in the first two years. They initially stated that the plant that is making them could make 250,000 per year.
Seems like the oil companies still have the upper hand and have enough control over GM to keep them firmly focused on selling gas guzzelers.
CM, I wonder if superconductivity could be used for energy storage. There are few materials that are superconductive in liquid nitrogen (boiling point 77K) which isn’t very hard thing to obtain. As far as I know small superconductive coil can hold a huge amount of electricity. Of course there would be constant loss by refrigeration needed, so that would not be very ideal for saving energy, but it could be useful as energy storage.
Anybody have any figures about energy density of such system? Scalability? Has anybody even tried to make such thing small enough to fit into car?
Not that it would be feasible currently for price, safety or energy cost, I’m just curious.
Well, here we go again! It’s that damm Stanford University, just keeps juggling and jiggling the storage world! Now it’s high-capacity lightweight paper batteries, coated with carbon nanotube and silver nanowire inks. www.popsci.com/science/article/2009-12/making-powerful-lightweight-batteries-nothing-nanotube-ink-and-paper . Roadsters and Model Ses will end up so light that they’ll blow off the road in a stiff breeze!
Why can’t physicists leave well enough alone?
:D
;)
Hi
I am interested in buying a S model tobring to Europe
Can you give me some more info. the country is Portugal
Ever thinking about pulling small trailer with power plant for driving very long rangch like Memphis to Fresno and back?
Uh, hello? Mr. Straubel? Anyone? It’s been nearly a year since the original post. Shouldn’t there be some updated info on the Roadster, as well as the Roadster Sport? Isn’t there similar information yet on the Model S? Preliminary results? Differences (if any) between the traction motor in the Roadster vs. the Model S? Battery pack testing for the 230 and 300 options?
@ Willis,
JB has already done this with his 944 PEV conversion. He sawed off a VW Rabbit at the firewall and towed the front wheel drive ICE and transmission package behind the 944 as a ‘pusher’ . Crude but it worked and had its own form of raw beauty.
From JB’s website: www.jstraubel.com/EVpusher/EVpusher2.htm
I just noticed that the Tesla Model “S” (the sedan) has a 0-60 mph acceleration time of 5.6 seconds. That is quite fast. I hate to be a party-pooper but, as a sedan, does it need much more than the 9 to 10 seconds, that a typical American sedan takes? I hate to mention the Prius but, even todays “3rd generation” model sells well with around 10.
Couldn’t building it with less emphasis on acceleration, bring greater range than 300 miles?
300 miles may be the lower end , before refilling, of a typical gasoline car’s range, but would increasing that do any harm? After all, recharging does take about “45 minutes”.
David,
There is a large difference between need and want. Most customers of expensive sedans expect high performance, even if they don’t use it.
The best thing about electric drive its that there is no tradeoff between peformance and milage. In fact if the car has higher acceleration, that means it also has higher regenerative braking and that leads to slightly more milage.
The Roadster uses 2.2Ah batteries, simply because thery are cheap (I hassen to add that Teslay buys the highest quality for reliability). Panosonic has 2.9Ah batteries and just announced 3.1Ah version. If customers are willing to pay a premium for these batteries, then the Roadster and Sedan could have almost 50% increase in range.
A Good blog. Have you had the opportunity to consider use of the waste heat from the battery pack and the motor and it’controller for heating the cabin? The AC can be useful in a heat pump mode. This configuration gives better than 3 cop Coefficiency of performance when the outside ambient is above 38 degreesF..
The double fuse per cell is over kill on a liquid cooled batt pack. There is much more ,But the time is 1:30 AM!
” Tesla motors is” The Right Stuff-
David E. Manwell
Electric motors have a very high efficiency over a very wide speed range and power output. Unlike a gasoline engine, reducing the power output of the electric motor would get only a little improvement in efficiency and range. On the other hand, that kind of thrilling acceleration and power makes it easier to sell that $50K luxury car. I suspect that the Model S might well become the least expensive car capable of doing 0-60 mph in 5.6 seconds, it will certainly be the least expensive 4 passenger sedan with that acceleration, and any gasser with that type of performance will be a terrible gas hog!
Reducing top speed has a bigger effect on range due to aerodynamic drag, but the Model S wouldn’t sell if it was limited to a maximum speed of 50 mph
Roy:
Electric drive is wonderful, but high acceleration still takes more work than lower levels of it. Doesn’t higher acceleration require more amps through the motor to get it? Getting get even more mileage would be made impossible by using that extra battery energy for extra acceleration. Losing no battery energy for snappier aceleration would violate laws of physics. Energy has no free lunch.
CM:
No, the model “S” wouldn’t sell well at 50 MPH top speed, but how about 100 MPH? That doesn’t turn off buyers of 100 MPH “gassers”, in the $50,000 price range.
Wouldn’t the inability to risk long trips, due to a lengthy recharge required only partly through a 500 mile daily drive be likely to turn people off?
David,
While it is true that higher acceleration requires more amps, the higher amperage is for a shorter time. It requires a given amount of work to accelerate to a given speed, but the rate at which it get there is not a factor. There is an exception, if the wheels are spinning then energy is lost to burning the tires. Your are right about Energy has no free lunch, but not correct in thinking it requires more energy to achieve a given speed quickly.
Re long trips: For the next several years people will accept the fact that they will usually be better off driving a gas powered car for long trips. Only when BEVs can drive 500 miles on a charge and a substantial charge, say 50%, can be done during a lunch break, will people use BEVs for long trips.
When will the Tesla have an onboard generator so that it will not need to be plugged into a.c outlet ?
Herb,
Tesla has expressed no interest in building hybrids. If you have an on board generator you effectively have a hybrid. Tesla is instead looking into battery swap stations and fast charging facilities. Once the infrastructure for those is in place the need for a generator will disappear.
I like the speed of a battery swap station, but I am not sure I want to give up my battery in exchange for one that is “in the system”. I worry that such swap stations may become a place people try to dump older batteries they have been charging at home for several years or that I may get a battery that has been abused in some fashion. Perhaps those concerns are not really justified (if everyone uses the stations all the time they should not be), but they are on my mind.
cablechewer: The only way battery swapping makes economic sense is if the batteries are leased from the swap company. That way, drivers are not swapping out their battery, they are swapping one leased battery for another. I would expect that any battery lease would include provisions for free replacement of any battery that falls below certain performance standards, and batteries that no longer had sufficient capacity for auto use would still have enough capacity for utilities to use for load leveling and backup power, extending their useful lifespan.
“Roy, what range do you think is the breakpoint for EV making ICE obsolete? You mention 800 miles in your answer to Kevin.”
Dunno about Roy, but I think the range is actually a mere 500 miles. That’s 4 hours each way with a little to spare. Longer than that and there’s already a better alternative to driving, most of the time (train or plane for big destinations, ATV or snowmobile for the middle of nowhere
), or you can arrange charging facilities at the far end.
A somewhat better ‘countryside’ train network would reduce the breakpoint to about 250 miles, which Tesla is already promising to be able to do reliably on the Model S.
Western Europe already has a dense train network and the breakpoint there is probably more like 120 miles, which can already be achieved routinely; as soon as Europe gets mass-production electric cars the gas cars will just go away.
—
Unfortunately I am still waiting for really solid data on cold-weather behavior. It does not get cold in California. It’s below 0 F today, with snow and ice, and severe winds. My garage is enclosed but not heated. How would a Tesla be behaving?…. Would I even be able to get it out of the garage? Would I be able to park it downtown, outdoors, being snowed on, not plugged in, for 4 hours and start it again afterwards?….
It seems unlikely from past information. :-/ Tesla seriously needs to put out a *lot* more information about cold weather behavior.
In canada its cold. The parking lots have had plugs for block heaters for the gasoline cars so the blocks dont freeze in winter for many years. So an electric car can just plug into the plugs already available in every parking lot. A Tesla pack has a heater to keep the packs warm. It seems easy to have a tesla car in Canadas north. Everything is already set up and has been for years.
New batteries with increased voltages can bring the distance more than 300 miles at highway speeds.
This is just what is easy to do.
Nathanael, cold weather testing has been done, at temperatures far below 0. The following posts might have the information you’re looking for:
Winter drive testing in Arvidsjaur, Sweden
www.teslamotors.com/blog4/?p=55
Environmental chamber testing
www.teslamotors.com/blog4/?p=43
A note on the tesla sports cross country in the middle of winter to the Detroit auto show. They will find out how it behaves in the cold and in winter storms. I wish it well. One Accuweather news weather report says ‘the worst winter storm in 81 years’. Another says ‘the worst winter storm in the midwest in 25 years; Another says ‘ It hasnt stopped snowing since December 29′ and has a picture of snowfall burrying a gas guzzler. Poor helpless gas guzzler. So where is the teslas 750? It seems like Its a bit like the movie ‘the great race’. the tesla 750 is just cruising happily along through the snow, narry a worry, nice and warm just getting to Cobo hall.
Weather advisory from USA - “AN INTENSE STORM SYSTEM WILL BRING A TWO-FOLD WINTER WEATHER
THREAT TO THE REGION”
Hello
im interested to now if tesla has tested the there cars in colder wether couse im am intrested in a Modell S and i live in FINLAND and here we have now snow and -30c . does the electrics work in any conditions or does it has any max cold temp
George, not all Canadian parking lots have outlets. In Southern Ontario outlets for block heaters in parking lots are virtually unheard of. I have heard they are common in Alberta and the Prairies.
I have been told by a Tesla sales rep that cold is less of an enemy to the battery than heat. It made sense given the protection the battery has against thermal runaway for the cells. However both extremes will cause some difficulty. In extreme cold steering will stiffen, brakes will be stiff and slower to respond and the battery will consume energy keeping itself regulated. Other than the potential for a slow drain of the battery none of this is any worse than my existing diesel powered car - in fact it might even be better because my diesel fuel is in danger of gelling at only -23C (exact temperature where gelling starts depends on the fuel & additive mix).
you may find this boring but I looked at the weather report and news for Shampaign USA when the Tesla car was there and the weather reports said that the wind chill was dangerous, and there were photos of people having to skii out of their neighbourhoods to get around and there were trucks swept off the interstate into the ditch by the weather and yet it was ‘just another day tor the roadster’ a bit windy but no trouble for the 750. The car travels well in the snow..
like “Ho Hum” i thought there was going to be bad weather. Well aparently there was bad weather but the people in the tesla did not notice.
Well the Tesla car is one of the few that can drive on the moon as is so I guess weather does not bother it too much.
I see a lot of people writing oh here don’t have a good understanding of physics. You cannot generate electricity to charge the batteries by putting a generator on the axle, or a wind turbine underneath. You don’t get something for nothing, simple as that! What the Tesla should have is regenerative brakes. I would think that for that kind of money, it should have it. Watch out Tesla! When the battery technology becomes economically feasible, Toyota, and Honda will beat your pants off!
Electric cars are nice however if they are to be truly affordable and feasible, then our electric power suppliers must be upgraded to handle the NEW load and the electric users in this country must convert to hyper efficiencies. The only, pending other developments, constant supply of electricity is hydro and nuclear.; solar and wind are not constant suppliers across the country. Any person buying electrics should be required to reduce their household electric use to a point to support charging an electric vehicle.
The Tesla proves electric autos are not dull and boring. but the government, utilities, and the people need to get the electric supply of the country figured out. Else we will all be green because we’ll be in the dark with no electricity.
The power grid of this country is not going to get fixed by auto makers nor battery technology matter if you can’t charge it.
The people need to get the electric supply figured out. This is correct since everything is old. there is 10 gigawatts of power every day hitting our planet from the sun which is enough to power most cities in the earth. so no power? no imense power is everywhere. How to use it?
One day the paint on the car would be sufficient to power batteries enough to drive 100 miles an hour across country.
the batteries will be many and computer controlled so when they are depleted, charged groups will supply the power while depleted batteries will go offline to be recharged in 10 seconds to superconductor levels. These nono batteries will be able to absorb energy directly from the environment and there will never be any need to plug the car in to recharge the battery. this is a future scenario. Is it fantastic? the technology to do this exists today.
Ken wrote:>
Sure - there will be competition. But consider the following aspects:
- Tesla has wisely remained independent from suppliers of cells and can source freely. Unless a competitor can get hold of a much better proprietary (to him) gadget, he has no particular advantage. The companies named are good car builders, but they are not specialists in electrochemistry.
- Large companies have their strengths, but speedy development of new products is not one of them.
- Do not underestimate the fine points of power electronics. Tesla Motors has a leading position that will take some time to erode. A particular problem for competition here is the lack of in-house expertise. The engineers needed are hard to come by.
Another thing: The Tesla Roadster has regenerative braking - very much so.
Ken: you are right about how wrong the idea of attaching generators to the axle and wind turbines to make unlimited range is. The people who come up with those ideas, over and over, don’t realize that generators and wind turbines produce drag, a resistance that is proportional to the power they produce, and on an electric car that drag would cause the motor to use more electrical power than they could produce in electricity.
On the other hand, Tesla Motors cars do indeed use regenerative braking, by using the motor as a generator they take advantage of that “generator drag” to both slow the car down and partially recharge the battery! The 3 phase AC induction motor Tesla developed is particularly well suited for that, it gives precise control of torque during acceleration and during regenerative braking.
I tell those people that what they are proposing would be a form of regenerative braking, and while that’s good when you want to slow down, it isn’t good to drive around with the brakes on!
How should the Model S be plugged in?
I would like to suggest, first, that it be made impossible (without owner- modifications) to drive away without unplugging the car. The car should not be operable without unplugging. If that has already been done, great.
Next, wouldn’t it be nice for the car to carry its own, permanently-attached retracting cord, so that none has to be searched for at recharging sites (especially at home)?
george;
your power figures are nonsense. There isn’t enough sunlight even in the desert at noon hitting the paint to power the car. Solar cars that get good speed and and range need huge flat table-top collectors on the roof, and are designed to run on bicycle wheels with minimal body structure and weight.
To protect users from potentially lethal shock, on the above, permantly connected, retractable charging cord, A diode be connected between the car’s recharger and the tracton battery, which restricting current flow to an inward direction only.
Brian H., george;
In good conditions Sun radiation is about 1000W / m^2 . Something like typical sedan has somewhere around 10m^2 area facing Sun at midday at the equator. That’s 10kW. Roadster would use around 50 kW at steady 100mph. And Roadster is smaller vehicle than typical Sedan. Current techs allow changing maybe 30% of that to electricity. You don’t get very fast to anywhere with about 3kW of power. With that power you hardly move at all with practical car in everyday conditions.
Also Earth gets a lot more than 10GW / day form Sun. Fom Wiki: 1.740×10^17 W. Multiply by 24 to get Wh / day = 41.760 x10^14 or 4.176 x 10^18 Wh
kilo=10^3, Mega=10^6, Giga=10^9, Tera=10^12, Peta=10^15, Exa=10^18 so that would be 4.176 exawatthours of Sun radiation every day. Much more than whole humankind uses in a year. About million times more if I remember how much our current energy usage is.
Is it possible to use regenerative braking and charge the vehicle while being towed (with power on and some still remaing)?
Would be handy to hook up with truck in the road out of nowhere…..
While all the attached information is quite useful, what is the true cost [Kw per mile as with mpg] ? Not using gas is one thing, but what will this do to my monthly ELEC bill ?
Mika,
Even if that works I doubt the tow truck driver would be impressed with what you are doing to their fuel economy. The regen braking would impose resistance for the tow truck to overcome. It might really stress the towing equipment and attachment points as well. Not an experiment I would want to try with a car that costs upwards of $110k (base price; delivery, options selected and a charging station or two add to it fast).
Mika; that’s entirely possible. It just feels like towing a car with brakes on, but some powerful truck wouldn’t notice Roadster behind it. Could cause severe strain to towing cable or chassis of the Roadster though.
David E. Manwell: Tesla cars are already set up with with an interlock to prevent driving while plugged in for charging. Tesla licensed a charging technology from AC Propulsion that uses some of the motor control circuitry for charge controlling, so obviously it can’t be driven while plugged in.
Mika: While it is possible to use regenerative braking to recharge the battery while being towed, that would be a “last resort” solution due to the strain on equipment and reduction of fuel economy for the tow truck. Much better to simply be towed to the nearest available charging outlet.
Steven Zimmerman: Unless your electrical rates are excessively high or low, an EV would use about 2 to 3 cents of electricity per mile. Average driving in a Roadster uses about 240 watthours per mile, or 0.24 Kwh per mile. For electric rates of 10 cents per Kwh, that would come to 2.4 cents. (hard fast driving would use more, gentle driving less) Compare that with gasoline costs from 7 cents (hybrid) to 25 cents (guzzler) per mile, and the fuel cost savings are clear.
CM - That´s what I meant, last resort obviously. If you are going to be towed anyhow, why not show some green to friendly (??) truck driver and get charged half way. I understand that regen is quite effective charger.
Timo, oletko jo tilannut autosi? Onneksi olkoon Suomi -tuo johtava sähköautojen (ja arvaamattoman autoverotuksen) tuottajamaa…….
Mika;
. En vielä. Odotan hiukan parempaa akkukestävyyttä. Type S akustosta ei ole vielä mitään tietoa ja Roadsterin 70% 50000 mailia ei ole riittävä minulle eikä paljon ajavalle siskolleni. Auto on myöskin hieman liian…miten sen sanoisi…karkki. Vähän vähemmän halibut My Ride -17″ kosketusnäyttöjä ja enemmän käytännöllisyyttä, vähän suurempi maavara jne. olisi mukavaa. Ehkä joku Type S -johdannainen olisi hyvä.
Explanation to everyone else who doesn’t speak Finnish (which is about 99.9 % of worlds population). Mika asked me have I already ordered my car, and commented about our weird car taxes and our leading status as EV manufacturer (sarcastic comment). I answered that I haven’t yet because there is no info about Type S batteries, and Roadster 70% after 50000 miles is way too little to me or my sister who also drives a lot. I also commented that Type S is a bit too much “halibut My Ride” -car with its 17″ touchscreens and stuff. I need a bit more practicality, slightly bigger ground clearance etc. Maybe some derivative of Type S would be sufficient, but Type S itself is not that.
I had an idea regarding electric cars which I’m not sure is viable, but would like to share. The electric car is limited by how far it can go on a charge. I understand that braking is routed back into the battery, extending distance, but would it be possible or feasible to include a small turbine to harness the wind when driving to recharge the battery? That way, when driving on the Interstate, the battery could be extended for greater distance as it is constantly being recharged, especially at higher speeds.
Andrew: Your contribution is one of many that have suggested a perpetual motion machine.
These never work because they fail to consider the machine’s internal friction. No matter how hard we try to reduce friction, some is always present. Energy must always be added from an external source to overcome it.
That’s why electric cars’ batteries must be eventually be recharged, which adds some energy from an external source, to replace energy lost. When the electric car is running, it’s overcoming the friction from its mechanism and that from the air it displaces. Your onboard wind turbine would also present its own friction. Batteries would still end up being recharged.
There is no free energy.
It’s also why gasoline cars have to refuel.
Timo
Tilasin S-mallin periaatteella, katsotaan miten käy. Varovainen arvio toimitusaikataulusta lienee 2013 joten rauhallisesti katsotaan mitä tietoa autosta tulee ja miten akut kehittyy. Kolme vuotta on pitkä aika ja uskon että toimituksia lykätään vielä pari kertaa, eihän edes tehtaan paikka ole vielä Teslassa selvillä. Voihan tilauksen peruakin tai kaupata eteenpäin, eli odotellaan….
I love Tesla - the first guys to get their head around the fact that cars in the future will need to be appealing, by that I mean look good and go fast to the point where perhaps mileage/range etc is much less relevant than appeal. How they sell those Prius’s to anyone I don’t know…. especially when you consider the amount of damage they do to the environment when they are made.
Mika; Minua häiritsee kenties eniten se 17″ infoscreen. Jos/kun hankin tuon auton niin pitäisi olla jotain kokemusta siitä miten hyvin tai huonosti tuo toimii syyspimeällä vesisateessa kun tiellä ei ole valaistusta. Pimeässä pelkästään mittarivalot tahtovat olla liikaa, tuo 17″ infoscreen voi olla monta kertaa pahempi. Lisäksi sitä pitäisi pystyä käyttämään katsomatta mitä tekee, 17″ tasainen levy joka ei anna mitään palautetta voi olla todella huono tuossa.
Mika;
Glad to see you took the plunge and ordered an S! 2013 is a year after the first models are due, so you have a fair chance of getting it then, I’d say.
Itselläni on VW Phaetonissa melkoinen screeni keskellä katselualuetta ja sen saa painettua pois päältä, eli pimeäksi. Ja sitten kun jotain haluaa tehdä, ruutu napsahtaa päälle eli ongelmia pimeäajossa ei ole ollut. Uskoisin että sama ominaisuus tulee myös S:ään sillä sehän on helppo koodata järjestelmään, helpompi kuin perinteiseen jossa siihen tarvitaan nappula. Eikä ole vaikeaa tehdä myöskään valosensoria joka pitää ruudun kirkkauden sopivana, toivottavasti auto tehdään ajatuksella eikä kiireessä.
Samoin aiemmassa Jagessasi oli kosketusnäyttö joka sopi mielestäni oikein hyvin autokäyttöön. Pois turhat nappulat joita pitää hamuilla.
Katsellaan mitä tapahtuu, lycka till.
sorry I can find, how do you solve car heating? we had -16°C yesterday. tks
Olda;
The car is heated electrically, including direct seat heating. It’s not a problem.
Mika;
One thing that concerns me is that if there is a display or software problem the car becomes unusable. So much dependence on a video screen is worrying.
Has there been any new designs that enables the vehicle to make and run off its own power with out recharging from an outlet?
Olda, the Roadster has an electric heater and electrically warmed seats. The battery has enough energy to keep the cabin warm for more than a day, even at -16, and it has been tested at colder temperatures than that.
Brian H: Wile the display screen is nice, and like most electronics is reliable, it doesn’t control essential functions and the car can operate without it.
Randy Reynolds: “Power” is just the flow rate of Energy, and there are no unlimited energy sources available. That means that any vehicle mush have it’s energy supply replenished from another source, such as liquid fuels or electrical recharging. Even “solar powered” cars need sunlight as an energy source. Now, there are some scam artists that claim to have an “unlimited power source”, but their devices never work the way they claim.
The battery pack is regulated when it is cold or hot to keep a specific range temperature. After a week of sitting the power range would go (for example) from 176 to 170 or so on a nice week. If it is really cold, or really hot as in california the power drain while sitting may be greater. Not significant perhaps but some may notice.
However when the car is sitting on the road, if there were new solar cells on the roof say. Then the circuites would allow the solar cells to charge the battery enough to offset the drain that the cooling systems are having on the battery. So when the customer comes to the car a week later, the charge of the battery is still half full, justy like when they left the car sitting a week ago, even if the temperature all week had been extremely hot. They should test this.