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Cost per mile to drive S versus comparable cost per mile with a gasoline equivalent?

Let's compare conventional gas cars and electric (S) cars in terms of dollars per mile (US), which is what the bulk of the world will care about.

Gas is about \$4 US / gallon where I live. Say my car gets 20 miles / gallon. Ratio these and you get

\$4 US / gallon
----------------- = \$0.20 / mile = G <-- call it G for cost to drive per mile using gas
20 miles / gallon

What's the number for an S, measured as follows:

\$X US / unit of charge
-------------------------- = \$X/Y / mile = S <-- call it S for cost to drive per mile using electricity
Y miles / unit of charge

Is S > G or is S < G? In other words, does it cost more per mile to drive an S than my car (focusing on fuel only)? Or, is the reverse true? Is this information somewhere on the Tesla website? Where exactly?

Bryan

Brian, you're right it's diffuse and you need more total capacity installed than your demand is at any given time. But the additional capacity need not be charcoal or nuclear. What you need is a mix of different renewables in different places across the country, and you need to invest in grid capacity as well. Hydro BTW is not only base load capable, it's also very easy and usually lossless to adjust to actual demand. Norway as well as Switzerland cover most (eh, a significant portion, lots) of their base load with hydro but you cannot do that everywhere, that's for sure.

P.S. If you find typos please keep them. I'm on my mobile.

T;
"Deep enough" is just hand-waving. The capital cost per KW capacity goes up exponentially as depth increases. And the thermal conductivity of rock places sharp limits on how much you can get from any installation. The best locales will be taken first, and some of them are very inconvenient (Yosemite, e.g.) Then you get to the harder, deeper ones. And the world can't function on power that expensive.

Look, for a moment, consider the much more likely option of success of the FocusFusion model. Minuscule costs, unlimited capacity expansion, no environmental degradation or location constraints, etc. It makes dreaming about human-built and controlled and exploited geysers look jaw-droppingly unrealistic.

Watch China. For all it's little throw-away demonstration projects and token green experiments, it's committed to industrialization by using coal, oil, and gas. And as China goes, so goes the world in the near to medium term, short of something as dramatic as FF.

V;
The "spread it out" argument is demonstrated by real experience to be false. Wind CAN drop across huge areas simultaneously, etc. And blows most (night) when needed least. FAIL. The UK is going to provide a lovely demonstration of how stupid and delusional reliance on it is.

Worse, the blithely assumed trade-offs etc. assume massive load switching and balancing capabilities: in other words, a pure fantasy transmission grid.

Examine the experience of the poster child Denmark. It actually gets to use very little of its vaunted capacity because it's on 'high' when unwanted, and off or low when demand is highest.

As soon as you look at the detail of any of the claims, they crumble.

My typo: "for all it's" s/b "for all its". 9-\

Re "100% backed up":

1. Most places already have sufficient generation capacity to provide this "100% back-up" level, so adding renewables to the grid doesn't mean we also need to build more fossil-fired plant; we'll just use what we have less intensively.
2. Nearly all parts of the North American grid have "rampable" generation on the margin nearly all the time. Pac NW in the springtime is a notable exception, but this situation is exacerbated by the lack of coordinated dispatch across the western interconnection. The Western Electric Coordinating Council is working on this issue.
3. Studies of the "Atlantic Wind" transmission project that Google and others are backing demonstrate that, at least in that region, the dispersion of off-shore wind generation along an extended geography substantially mitigates volatility that will inevitably occur at any one site.
4. The interconnected grids already carry substantial reserves, because s*** happens, regularly. Adding variable-energy resources adds a new source of uncertainty (to sudden power plant outages, transmission outages, load swings, etc.), but because it is largely uncorrelated to the other risks, it does not necessarily require carrying larger amounts of reserves.
5. We're all signing up to buy what could be a valuable part of the solution: EVs. It is not unrealistic to look forward to a level of grid control in which, when we plug in our EV in the evening, it informs the utility that the EV is ready to be charged and when it needs to be available next. The utility can then charge the vehicle to conform to the grid needs.

FWIW, I head a global energy consulting practice and work with major utilities and generation owners on these issues. "Grid integration" of variable energy is a critical topic, and one that the industry is taking very seriously.

well denmark at the moment is exporting all available power to germany, because they have stopped a couple of atomic power plants

normally Norway will bye our excess night power(cheap), and slow there own hydro production
and during the day(expensive), they will increase the hydro production
byeing cheap danish wind power and sell expensive hydropower to us
it is not that hydro is more expensive to produce, they are just able to scale production dependen on the price
but in the end it keep the price more stable, and it is more profitable to sell it cheaply to norway than stop production

http://dkkort.elmus.dk/ (map that show live power production in Denmark)

We also have pumped storage in Norway so we can use excess or cheap power to pump water back into the reservoirs, then using that water for power production later. The efficiency of this arrangement is about 85%. The hydro plants can be ramped from 0% to 100% power output in less than a minute.

One huge flaw in all these comparisons is that they ignore a very big factor : the costs of the batteries. Batteries can, at this stage, be considered part of fuel costs. Certainly a \$40K replacement cost for Tesla's 300 mile pack every 9 or 10 years
puts the cost of driving the electric in this case a lot more expensive than an ICE. Unfortunately, all too many EV advocates
argue as though battery costs, beyond the initial costs, simply do not exist and thus claim wildly optimistic benefits for driving electric. Now, the DBM-Energy batteries claim a 5000 recharge
capability, resulting in a battery pack that could easily outlast 3 or 4 cars. If that turns out to be true, then electric cars
should be manufactured and merchandised both with and without battery packs. Methinks the future world of the automobile may
be far more different than many imagine.

Lose a zero. 9 to 10 years \$4000 would be closer the truth. \$40k isn't true even now. Roadster battery change is \$12k.

If you're going to amortize in the battery replacement cost to your "per mile cost" calculation, then you should compare to ICE car numbers including oil changes and everything else they need to keep running.

EdG, Ramon123, look for the following post earlier in this thread:
jfeister | May 10, 2011 - 11:20am

I think most people on this forum agree with jfeister, at least no one objected.

EdG is right - you have to compare TCO with TCO. ICE will have issues to deal with like adjusting valves, exhaust system, catalytic, spark plugs, fuel tank, fuel filter, fuel pump, air filter, turbo or super charger issues, etc. that an electric car simply will not have. Who here has had a major tuneup done and they tell you that you should change the water pump because they have to disassemble a lot that's in front of the water pump.

There will still be things like power steering, power brakes (you can't rely 100% on the regen to stop you), A/C, etc, but a LOT less than the typical ICE.

On the other hand, the EC does have this big honking electric motor but they have been around for quite some time and are very reliable. There will be some electronic death here and there and while that should be relatively inexpensive we all know how much we get raked over the coals for automotive parts in general, let alone highly specific, specialized parts.

Then there is maintenance that will be on both types - tires, bearings, tie rods, etc.

Over all, I expect the EC to cost somewhere between 50-75% less in maintenance over the life of the car (say 10 years) - on average. This means that there may be individual variation - that always happens.

Now, about the cost of the battery. Remember, the 160 mile battery is in the base unit - the 300 mile battery is \$20k more. That means that the 300 mile battery costs AT LEAST \$20k !!! I was actually quite shocked by that. I figured the 230 mile battery would be 2.5-5k more and the 300 mile to be another 2.5-5k, but 10k for EACH jump, well, that seems to be a bit ridiculous. They're probably trying to suck every last penny out of the initial group of early adopter that they can, which is typical in any release of new technology.

As for me, I'll just be happy with the 160 mile battery (for now).

To complete my thought here... Unfortunately, we don't know how much the base 160 mile battery replacement will cost and since they won't have to sell any of them for another 7-8 years or so, we may not know how much they cost for some time.

I would hazard a guess, based on the incremental amounts that the base cost of of the battery is somewhere in the 10-20k amount. Let's figure it for both values and see what we come up with.

Over 8 years - 100k miles. At \$10k, that's \$0.10/mile If the cost is \$20k, then that is \$0.20/mile. The other question to ask is - what "trade in" value will the old battery have?

Here's my scenario - I drive about 15k miles/yr. I would like to hold the car for at least 10 years. That's 150k miles. I can deal with a shorter range than 160, in fact, I can actually keep using it until it drops down to somewhere in the 80 range.

Electricity here is \$0.16 c/kwh - using the 300 wh per mile, I have 0.3 kwh/mi * 150k or 45k kwh or \$7200 for electricity.

Do the comparison for gas at \$4.00/gal assuming 20 mpg - i.e. \$.20/mile and you have \$30,000 for gas. That's a net savings of \$22,800. There is some time value of money to take into account, but if the cost of the car loan is at 3-5% isn't not that much right now.

Now, if I have a car that gets 30 mpg, that changes to \$20,000 for gas and a savings of \$12,800. That also assumes that gas does not go over \$4/gal in the next 150k miles (i.e. 10 years or so). We all know where that number is going.

The tables definitely look to be tilted in favor of the EC and they're tilting more and more every day. But, who knows what's going to happen to the price of electricity too - in the end, it's a big gamble, but I do know that I'll feel much better about not sending my money to the oil companies (my electricity comes primarily from Nuclear).

There are actually two viable types of nuclear reactors used by utilities - the conventional light water reactor that's been in continuous use for the past 60 years, and the fast breeder reactors, which exist in several countries but have not yet reached commericialization. Fast reactors have many advantages over light water types - they can extract virtually all of the energy from the nuclear fuel, rendering it relatively impotent in terms of storage. There is enough energy left in our "nuclear waste" (it's not really waste) to provide 100% of the power needs of the US for the next 1000 years. No more uranium will be required until the year 3000. Utility reactors are large and
generators stepping in when power requirements during the day exceed what the reactor is providing. However, more than a few
have associated pumped storage reservors which allow excess power generated to be used later when needed. There also exist small nuclear generators, one championed by Bill Gates for a remote village, built by Toshiba or Mitsubishi I think. It's output can be varied as required, and thus it functions as a peak load generator. It is fueled at the factory and buried underground - it's about the size of a bathtub. It can produce 20 MWs as I recall at a cost of around 5 cents per kilowatthour. It can operate for about 25 years before needing to be refueled.

It's quite impossible to even guess when it comes to cost comparisons between ICE and electric cars. There are way too many unknowns here. For example, the cost of the battery must be considered and that's a really tough one, in an age of rapidly
changing battery technology. The 300 mile Tesla Model S battery
looks to cost \$40,000. Now figure your cost comparisons using battery costs. You really can't because you don't know what the replacement battery is going to cost, except that it's obviously going to cost less, in real terms. Same thing for fuel costs. You can only make comparison at given time and place. My electricity is a lot cheaper than California and Mass and NY electricity, but more expensive than Indiana power, etc. Gas prices are changing almost daily. There is no fixed relationship between the price of gasoline required to move your car 4 miles down the road and the price of electricity required to do the same thing. Trying to make comparisons on the basis of energy contained in a gallon
of gasoline versus that contained within a kilowatthour has no value with respect to costs.
The reason I'm not out rushing to buy a Model S has nothing to do with the vehicle per se - I think the design is outstanding.
It has to do with the battery. If the German Federal Government laboratory that tested the DBM-Energy battery pack was accurate, that battery will last 30 years, or 5,000 discharge cycles. The battery also has zero problems with safety issues and doesn't need
a system to maintain its temperature. And it can be recharged in a few minutes, apparently. So you see, I simply don't want to fork
over \$40,000 for a 300 mile battery pack and find out the batteries are obsolete the next day. I don't have range anxiety, I have battery obsolescense anxiety. Whether I'll spring for the
160 mile version I don't know : even though the "loss" would be less, there would be the question of getting the new batteries into the car. I want more clarity on the all-important battery question before leaping.

Ramon;
Not proven and produced yet, but check out the work at LPP.com . If they meet their schedule for having their mini-fusion reactor on the market in the 5-10 yrs. range, it would be making power at about 1/10 the cost of those small fission jobs. Above ground, no waste, no radioactivity.

How does 0.25 - 0.5¢/kwh sound to you? ;)

I tech industry there's always better technology around the corner. If you base decision of what or when to buy a technology product on what will come in the future, u will never find a good time to buy. It's better to just buy something that covers your needs now. You can always buy new technology later and sell what you have to someone less demanding.

My experience is that being an early adopter of any new technology is virtually always a bad way to go, assuming that cost is a consideration. Take practically anything - PVs for example. The first ones that came out couldn't really do anything and cost over \$4,000. Or solar panels. I have been following this technology for over a year and can state, without hesitation, that installation even as recently as a year ago, would have been a very bad decision, despite Fed subsidies of \$1K per kilowatt of capacity.
Not only have microinverters made installation an easy task even for the electrically challenged, and cutting over half the cost of system installation, but have increased energy harvest. The pricing of the panels themselves has experienced a severe drop. Two years ago the prices were more than double what they are today. And the panels are better and will likely outlast you. And net metering is available practically everywhere nowadays as well.
The technology is reaching a plateau in terms of harvesting efficiency and competition is cutthroat, reducing prices as low as possible thru mass production, unless some new scheme for manufacturing comes along. I would recommend buying at this point - my estimates are that one can, by installing the panels yourself, obtain a fixed price for electricity for the next 25 years of 5 cents or less per kilowatthour in virtually every locale in this country, sans the far north.
As for electric cars, they behave more or less the same as what we have today, so the only benefits concern the fuels they use and emissions they (may) reduce. Anyone who claims "I'm doing my part" to reduce either of these things, I simply say: "Hogwash." One person cannot make a difference here. And at these prices for batteries, there cannot be very many early adopters. Even a million adopters would have virtually undetectable effects. In many locales, actual carbon emission reductions are either nonexistent or insignificant. And even where they are significant, the costs of reductions obtained by using an EV are exorbitant compared to alternative means. Electric cars have enormous advantages in every respect over an ICE powered vehicle, but the battery costs are simply too great at this point, at least in terms of cost effectiveness and widespread availability, despite a rather enormous \$7500 subsidy from our generous Feds.
Just as it has been thruout its history, the widespread success of the electric car all comes down to its battery, and nowadays, only to battery costs, since I believe that they are advanced enough to compete successfully in terms of functionality (recharge speed, driving range, etc.). But costs involve not just initial but also lifetime costs, although some new designs apparently have
I will wait on EV technology just as I did for PVs and solar panels. I made out like a bandit on those and expect to do the same on EVs. Besides, Tesla has sold its output already and
doesn't need any help from me to succeed, which I hope happens
in a big way.

For new techs this current time is going forward in incredible speed. Nanotechs in medics, quantum computing in solving problems, carbon nanostructures in just about anywhere etc. In next 20-50 years our world will look quite a different place.

For EV batteries I predict 75% price drop in next 10 years for two reasons: 1) volume of production raises several times higher than it is now which reduces production costs. 2) new techs make Wh/L much much higher than it is now.

BTW. if Model S uses 8000 cells in its battery pack, that equals about 1300 laptops. 5000 Model S equals then 6500000 laptops. That's a lot. It doesn't take long before automotive battery production exceeds any other battery production needs.

Ramon123:

(think Tom Smothers :) Oh yeah, yeah?

Well, all of us early adopters who are getting more than the 160 mile version will have SO much battery space that when it comes time to replace them the battery technology will be so advanced that the replacements will cost \$5000 and take us for 3000 miles on a charge. (Which, from empty, will take 3 days to recharge.) And we'll be so ubiquitous that power companies across the nation will pay us to act as energy storage depots so that, when we're not driving, they can tap into us at peak demand.

All battery packs are the same physical size. They are just more or less filled with cells of different chemistries. The new batteries will probably not be so advanced, probably, optimistically, \$10k and 800-1000 mi in 10 years.

Check with your local power company. In planning for my model S, I checked with my power company for special requirementsd, etc. Mine offers a discount for off peak charging.

Hydro is in most ways the ideal electrical generation for grid purposes, but as someone said, it's limited by the fact that we've already used all the good locations. (Niagara Falls, for instance.)

The baseload problem is not a serious problem. Energy is used very inefficiently right now, *particularly* for baseload, which is mostly lighting and heating, and the baseload demand could be cut substantially by efficiency improvements which are already available. Peak load is actually more of a generation issue, because it's less amenable to efficiency improvements, and for that solar is ideal since it correlates with peak load; of course it has to get more efficient, but it is doing so at astounding speed.

Getting back to topic, I did attempt to run a TCO comparison between the Model S and the gasoline car I would have otherwise gotten. I didn't post it because there are simply too many variables. The electric car costs more upfront, but costs much less to run. If you have to finance it with a loan, it's probably not worth it. If you don't, it depends on how long the battery lasts, the future price of oil, the future price of electricity, and critically, the 'salvage' value of the car when you retire or replace it.

There are revolutions in battery technology coming down the pike in the 5-10 year timeframe (my father's currently trying to get one commercialized), but I decided I want off of oil NOW. I'm predicting that most gassers will have no resale value in 10-20 years and that the Tesla Model S Signature may be collectible and will have resale value.... which is why I concluded that I'll probably have a better TCO with Tesla. Tesla's designed the car to allow for battery replacement in any case.

If you ignore the resale/salvage value issue, you can get *some* numbers, but it depends on your driving habits. I advise figuring it as follows: figure out the difference in price between the Model S which you would get and the comparable gas car which you would get otherwise -- call this hte "premium". Then pick a price for gas which you think will be the average over the period of ownership; this gives you a dollars-per-mile for the gasser, and you can subtract the (tiny) dollars-per-mile for the Tesla (electricity is unlikely to skyrocket in price, more likely to go down). This gives you the per-mile price difference. Multiply that by the number of miles per year you drive, and you have the dollars-per-year difference (though you should add in the difference in costs of maintenance here). Divide the premium by the dollars-per-year to figure out how many years it will take you to save money by buying a Tesla.

I drive very few miles per year (maybe 2000), and I have to get the large battery due to my location and recurring long trips. So for me the payback period is something like 30 years at current gas prices; I'm not saving money unless I consider resale value. If you can do all your trips with the 160 mile battery and and you drive a lot of miles per year, in contrast, you'll have a rather fast payback period. You have to run the numbers for your own situation.

I should note that actually number of miles driven per year is the most important number in the TCO computation. Because the Tesla costs more upfront but less per mile, it is *much* more cost-effective for someone who drives a *LOT* than it is for someone like me who only drives a little.

For Solar panels
1 mile / 0.300 kWh. 12,000 miles per year = 3,600 Kilowatt Hours.
3,600 divided by 365 days = 9.83 average kilowatt-hrs/day needed
9.83 divided by average sun hours per day, my location is 5.5
= 1787 watts needed, with derate factors lets say 2000 watts
2000 watts divided by a 235 watt panel = 8.5 panels
9-235 watt panels @ \$550.00 = 4,950.00., AC inverter 2,000.00., Installation 3,000.00 = 9,950.00, minus tax credits and rebates
5,900.00
Solar panel lifespan 25+ years

Gas engine
12,000 miles @ 22 mpg average passenger car = 545 gallons
545 x 4.25 = \$2,361.00 x 25 years = \$59,025.00 - \$5,900 = 53,125.00
savings over 25 years if gas prices stay at 4.25 a gallon.

To finish your computation, b300sd, one needs to know how many times one will have to replace the Tesla battery over the course of 25 years, how many times one would have to replace the gasoline car you are considering as an alternative, the costs of both, and the resale value of both type of cars at replacement time. Oh, and interest rates (the time value of money).

I have no idea about some of these. There really are a lot of variables, and which ones you think you can predict -- are probably different from the ones I think I can predict. :-)

(Sorry for cross posting this link, it erroneously went into the wrong thread at first.)

autobloggreen: How gas cars use more electricity to go 100 miles than EVs do

"Let's go over that again. If we simply count the electricity used to make the gasoline that gets burned in a normal vehicle, you need more juice than you do to move an EV the same distance. Of course, then you need to factor in the actual gasoline used (and the resulting CO2 emissions). Plus, don't forget, it takes a bunch of water to refine gasoline. Put this all together and you've got on hell of an energy efficiency argument in favor of plug-in vehicles."
http://green.autoblog.com/2011/10/14/how-gas-cars-use-more-electricity-t...

Reason why you wont need much more electricity for EV:s is that refining gallon of gasoline takes about 6kWh of electricity. That's 20mile worth of driving in EV, so your current ICE car is actually using same amount of electricity as EV. (Timo)

Funny, Elon uses your argument almost literally in a recent interview: "[...] you have enough electricity to power all the cars in the country if you stop refining gasoline. You take an average of 5 kilowatt hours to refine gasoline, something like the Model S can go 20 miles on 5 kilowatt hours."

Chris Paine (the "Electric Car" filmmaker) adds: "It does not include transporting it from the Middle East or Venezuela. The more efficient your refinery is, the lower that number is. The lowest number in the DOE study I read was 4, and the highest was 7, it depends on what your refinery is."

Here is the interview: