Forums

Join The Community
RegisterLogin

Cost to fill

So I have been trying to calculate the cost to "fill" an empty "tank". Here is my math. It seems low, help me find the error... Or spread the good word!

Power per mile: 300Wh (per FAQ)
Miles per "tank": 300 miles
Power per "tank": 90 kWh = 300 * 300 / 1000
Cost per kWh: $0.09 (in NC, varies by location)

Cost to "fill-er-up": $8.10

@Mycroft: I think our best long-term energy solution is a combination of ocean wave, solar, and land-based wind, linked to storage. "Ocean waves?" you may ask. Yes -- the energy density of moving water is vastly higher than that of moving air or sunbeams. Higher density leads to lower costs.

The storage piece in the middle is critical, though, and there's no reason that EVs shouldn't be part of the solution.

Zelaza correctly points out that my cost estimates are highly dependent on the assumptions. Let me demonstrate:

Suppose that you look over only a 40-year period (which doesn't really change the basics). Now instead of assuming constant (real) prices, suppose that (real) prices grow by:

Gasoline 5%/year (depleting resource)
Electricity 3%/year (increased capital intensity for renewables)
Batteries 0%/year (technology improves)

Under these assumptions, the NPV of the net gasoline costs (at 3%) is $144,597, compared to the NPV of the battery costs of $51,988. Thus, there's a savings of $92,609 on the EV route -- again, without considering any other costs/savings of ownership.

Your mileage may vary....

Or put a different way, you'll spend $173,724 on gas, $29,126 on electricity, and $51,988 on batteries (all NPVs).

@Mycroft, Robert, you forget geothermal. That's still in infancy state for deep crust applications, but is in use in places where heat source is closer to surface. That's also a source that is practically unlimited and does not depend on weather or time of day at all. For many places that is way better than solar or wind, and you can't harness all the rivers for hydro. Ocean waves need Ocean nearby (or long distance distribution network).

@Zelaza - you seem to breeze by some key facts in your battery price discussion. You mention that 10 years ago you could buy a AA battery for $0.50 and today for $1.50, but that is ignoring the relative capacity of those AA batteries.

I think a look into cellphone battery prices over the past 10 years would be much more accurate, though I don't think you will find a single LiIon battery 10 years back...

I still think I will beat everyone on battery prices as I plan to buy a 160 mile pack now, then in 5-10 years buy someone else's used 300 mile pack for peanuts with something close to a 230 mile remaining capacity. In the case that new battery prices are cheap enough, I might consider a longer range option.

@Robert.Boston:

Thanks for your calculations. While I'm apprehensive about the utility of considering a forty year period, I'll use your numbers to try to analyze a hybrid drive, which I think is necessary for a majority of vehicles during a 10 to 15 year transition period from gas to mostly electric vehicles. While I hope the transition period is less than your forty year period, I'll use your 40 year numbers.

The basic transition plan is a hybrid vehicle with a suitable ICE and smaller battery; specifically, a battery half the current size in your calculation. To provide for the weight of the ICE and generator we have the 500 lbs freed by dumping half the battery. To pay for the ICE arrangement (estimate at $10,000) we have about $20,000 from half the cost of the battery of the BEV; thus, actually, an expected saving of $10,000 in initial cost. With this arrangement, the 40 year operating cost using your numbers is as follows:
First assume that the ICE is used for only 10% of the mileage (to give unlimited range and recharge batteries) with the electric drive train used the remaining 90% of the mileage.
1) Using the ICE 10% of the time gives total a gas cost of 0.1x$173,724 = $17,372
2) Using the electric drive 90% of the time gives electric cost of 0.9x$29,126 = $26,213
3) Since the battery is only half the previous size, its expense is 0.5x$51,988 = $25,994
4) The expected 40 year operating cost of the hybrid is then:

$65,979

This compares very favorably with your BEV 40 year cost estimate of:

$81,114 (= $29,126 + $51,988)

Another point I won't elaborate on here (for the pure BEV) is the total time required to recharge a battery whose recharging cost for electricity is $29, 126. This recharging time is a little over 13,000 hours = 542 days = 1.48 years.

There have been previous important transition periods and one that comes to mind is the transition in shipping from sail to steam starting in the 1840s or 1850s (not sure, and unwilling right now to look it up.) At first ships applied paddle wheels timidly but kept their sails and relied on them most of the time. As the more efficient screw propellor was developed there was more reliance on steam than sail but still no one would risk a ship or cargo on steam alone. The big problem was running out of coal and numerous coaling stations on foreign shore were established; some requiring war. I believe that as late as the 1920s, some steam ships were still being built with masts for sails. Ironically, now some very large high-tech ships are being built with masts and self deploying sail like structures to save fuel.

Another thing to consider is that China and India are getting ready to come on line in the next decade, and their energy needs are going to be massive. Oil is open market, and even if every car in the US went to alternate fuel, the price of gas will continue to rise. Switching demand away from oil domesticaly won't affect long term oil prices. I'm guessing 10 years from now gas will be closer to 8 bucks than 4 bucks. But that's just a guess.

Although the cost of filling the S will be less than filling a gas tank, I have no thought that I will save money OR energy by buying a Tesla. I don't drive enough to have the cheaper fill ups (and other savings that have been mentioned) pay for the added capital cost. There are a lot less expensive cars available.

And for saving energy, it takes a lot of energy to build the car. I have read a car requires as much energy to build as it uses in its life. If you want to save the planet's available energy, keep your present car or buy a used one.

But I want something unique with a big WOW factor. You cannot put a price on that.

Something I have been thinking about for a while is the supply line of gasoline. Let's say that electric vehicles become prevalent and that gas consumption drops drastically. Demand dropped big time, but it is still required for things like lawn mowers, trimmers, etc. I know electric versions of those exist and have for a while (I even have both examples in electric), but the point remains that it will take us longer to eliminate gas usage than to drastically reduce it.

Back to the point, if gas usage is low but still required, people will still be buying it. It will still require a vast country-wide supply chain and all of the costs involved with maintaining that supply chain at a lower volume (truckers to haul gas to stations, tankers to bring gas to the country, etc). I have a feeling that the reduction in cost for the supply chain will not equal the reduction in revenue for those involved and prices will rise despite demand decreasing.

I am not a business person or in finance / economy so I don't know if my logic holds up, but I don't think gas prices will maintain their level if gas usage decreases, and I fully expect that decrease in use to happen.

@mwu: The end-state of your utopian vision of all-EV cars is actually pretty easy to deal with: gasoline becomes a specialty product, not unlike propane today. You'll buy it in gallon containers at hardware stores, marine supply shops, and sporting goods stores.

It's the transition that becomes nightmarish for the ICE hangers-on. If only, say, 20% of the cars run on gasoline, how many gas stations will there be? They'll start suffering from range anxiety.
Winking Smiley

@cerjor, building a car doesn't use nowhere close as much energy than driving it in its lifetime. Maybe 1% of entire energy cost and I think even that is overestimate. At least for ICE cars, for BEV difference is smaller (around 10% efficiency vs. 60% efficiency whole chain considered).

As always, I ask for references... Can any of you, Timo, cerjor, cite your sources? It's an interesting topic, and actually I think I read something somewhere as well, but hearsay is a doubtful basis for discussion.

Last weekend, I was at a Nissan dealership talking with their Leaf salesman. I asked him "Suppose I roll into a Nissan dealership with a Tesla Model S, and ask to use the Level 2 charging station to refuel? (Assuming we have a J1772 adapter)". He said "No problem. All PEVs are welcome to recharge - for free".

Awesome. So, for at least some time to come, there will be many random opportunities for "free fuel" in public locations. (David M.)

Good to know but it seems like you cannot necessarily count on all Nissan dealers being equally friendly:
http://www.greencarreports.com/news/1067476_how-far-left-on-my-leaf-elec... (first few paragraphs)

I can't vouch for this source's accuracy, but a reply on Google Answers quoted a broken link to www.greenercars.com as saying:

Automobiles affect the environment in many ways. Impacts begin when a
vehicle is manufactured (including the production of all the parts and
materials that go into the car) and end with its scrappage in a
junkyard (which can recycle many parts but also involves the disposal
of many wastes). Over the life of an average motor vehicle, however,
much of the environmental damage occurs during driving and is greatly
associated with fuel consumption. Over the dozen or so years of a
vehicle's life, nearly 90 percent of lifecycle ("cradle to grave")
greenhouse gas production for a typical automobile is due to fuel
consumption.

I have a flu and frankly am too tired to dig up any sources right now. It's tedious task considering that you need to discard a lot of bad information that is pure propaganda (at both directions). D*mn politics.

Dig up something anyway:

http://answers.google.com/answers/threadview?id=433981

Looks like 5-8% of energy is for manufacturing based on that. Something like that. Could be that "lifetime" is longer in other calculations, and it definitely will be long for BEV:s.

It's tedious task considering that you need to discard a lot of bad information that is pure propaganda (at both directions). D*mn politics. (Timo)

That's precisely the reason why I keep asking for sources... :-) Thank you both for making the effort, and Timo, get well soon!

Thanks Timo, that answer was pretty in depth. We should make more Aluminum intensive vehicles apparently.

There are some thoughtful comments in this chain. I think it is clear, and has been for some time, if you're out to save money, then buying a Tesla probably isn't going to get you there. But of course, neither is buying a BMW, Mercedes or Audi. People don't buy $60,000 cars to save money.

The old "electric doesn't save money" arguments are a but tired aren't they? I had a hybrid Lexus and loved the fact that I could drive 500+ miles on a tank of gas. To me, that was an option worth paying extra for. If you're asking whether the extra cost of the electric motors was "worth it" then why not ask whether the leather seats were "worth" the extra cost or the premium sound system upgrade was "worth" the cost. These are not things that have a true value, the value is in the fact that I was willing to pay more to have the features I wanted, which in that case included a very high mileage, low emission, quiet engine. Ultimately, I dumped the Lexus because I couldn't drive a dorky sissy car anymore and I went back to a BMW. And guess what? The mileage sucks, the NAV system is a joke, the iDrive is an abomination, but I still like the BMW better. In the luxury car market we pay up for the features and emotional appeal that we want. It's not about penny pinching.

That said, when comparing the Tesla to an ICE vehicle, let's make it a fair comparison. How much extra does it cost to make a BMW 5 series do 0-60 in 5.6 seconds? What's the maintenance cost on such a highly tuned engine? How much time would one spend at the gas station filling up the tank? And what's the cost of making that ICE silent and emission free? Priceless.

@Achilz

"There are some thoughtful comments in this chain. I think it is clear, and has been for some time, if you're out to save money, then buying a Tesla probably isn't going to get you there. But of course, neither is buying a BMW, Mercedes or Audi. People don't buy $60,000 cars to save money."

I think you've hit the nail on the head. But please don't be too hard on us, these discussions around "economics" help us rationalize an expensive emotional driven purchase. ;-)

Larry

I stand corrected. Thanks Volker-Berlin. Following Timo's suggestion of references I tried to find the one I had believed in. Couldn't find it but found that the manufacturing energy to be much less than that consumed in driving. Here's some quotes from the search.

"The U.S. Department of Energy's Argonne National Lab has developed a scientific model to analyze the energy input involved in automotive manufacture. This is known as the Greenhouse gases, Regulated Emissions and Energy use in Transportation model (GREET). It breaks down manufacture into component parts and traces the base materials to their source and extraction.

Using the GREET calculations, a 1996 Mitsubishi Montero weighing 4,290 pounds took 135,542,980 Btus of energy to make. In terms of energy usage we can say it consumed 1,850 gallons of gasoline (a gallon of gas being equivalent to 113,500 Btus.). A 2009 Honda Civic, although 300 pounds heavier, only consumed the equivalent of 715 gallons. It also has better fuel consumption on the road."

Another site referenced the same Argonne study and concluded, “Typical cars used 20 % of their total life cycle energy for production, and consumed nearly all the remaining 80 % as fuel energy.

cudos to zelaza and the rest (mostly) to keep this interesting discussion free of flaming and insults. Buying a car IS a highly emotional move, and we all search for rationale until we find the one serving our emotional preference (Prof. Fügener, teaches car design).

Another thing to consider is that when comparing battery costs vs. buying gasoline is that you get 10 years or 100k miles nearly free with the EV. All you have to pay for is the electricity. Not so with the ICE vehicle.

In reality you could subtract the $20-30k you will spend on gasoline from the Model S because it comes with a battery pack included, while you have to add that $20-30k cost to the ICE car.

After 100k miles you MIGHT need a new battery, but you will for sure need more gasoline and maybe extensive repairs to drive another 100k miles in the ICE.

Achilz said...

"And what's the cost of making that ICE silent and emission free? Priceless."

I was just thinking about this the other night as I was gagging on fumes from a vintage Beatle for 10 miles after having been stuck in bumper to bumper for a half hour with a bunch of other smelly cars...

I can't wait for my Tesla, and I'll be even happier when the guy in front of me gets one too.

I can't wait for my Tesla, and I'll be even happier when the guy in front of me gets one too. (jbunn)

I couldn't agree more.

Regarding serial hybrids vs. pure electrics, I agree that the economics probably favor serial hybrids right now.

I just want to get *completely off* of gasoline. And I don't like all the maintenance which gasoline generators require, let alone the maintenance for parallel hybrids. Nor do I like the exhaust. So, yeah, I'm paying extra to get a BEV rather than a hybrid.

On another point, I happen to know that battery technology is going to get much better within the next 10 years or so, as will the efficiency of solar panels. Don't bet against either. Arguably, in pure economics terms I ought to wait for the much better batteries to be available, but I want my electric car NOW.

What can I say? I rationalize the cost by believing that the Model S will become a collector's item. "A genuine antique, from the early days of the electric car revival, back when they used lithium ion batteries!" :-)

I feel almost identically to ncn. I've never bought a new car since I hate the crazy first 2 years of depreciation, and if I were making a pure rational decision I would wait 3 years and buy one used, but in this case I think it is important to push the market in the right direction.

If companies don't make money doing the right thing, they will not keep doing the right thing. It is critical that BEVs are more successful than the pundits expect. We can't afford to let the big automotive companies passive/aggressively kill the EV (again). Without the outsider influence of Tesla to prove that it can be done successfully, they (big auto) can make it fail all the while looking like they are trying to make it work.

Lefingal,

I doubt you'd find a used one in two or three years. I think most of us that want to get a Model S intend to keep it quite a while.

I suspect it'll be at least three years before anything else comes close to meeting the specs of the Model S.

You may not get it cheaper in 3 years. The market of used Model S will be very small and the line for a new one will be quite long. Take a look at the market of second hand RAV 4 EV. Some have sold several years later for more than the original price.

If they offer 3 year leasing contracts some ppl will lease a new one after 3 years, and the 3 year old cars will be sold as used. That way ppl that have te money, and are willing to pay for it, will have the updated tech, and don't need to think about the battery pack getting older. It's all included in the price of leasing.


X Deutschland Site Besuchen