I posted earlier in this thread that I absolutely consider Musk an innovator. And I also view this 'welfare' claim against Musk as unfair and twisted. As others have said, he is apparently playing by the rules, and that's smart. If you don't like the rules, talk to your Congress-person (but please don't argue it here or the thread will get locked!), and I don't blame Musk for using them.
But here is where I have a problem - those rules were intended to promote the environment, and Tesla is misleading (to put it mildly) the public about the 'green-ness' of EVs in order to keep this game going. Take a look and judge for yourself:
This Tesla blog:
The Secret Tesla Motors Master Plan (just between you and me) | Tesla Motors
references this Tesla 'White Paper”:
http://web.stanford.edu/group/greendorm/participate/cee124/TeslaReading.pdf
The pertinent section is where Tesla claims the Roadster “Well-to-Wheel” efficiency is 1.78x better than a hybrid (1.14/.64) and 2.24x a standard gasoline car (1.14/.51):
see thumbnail below
These numbers were critiqued (often unfairly, IMO) on other sites, and here is one Tesla owner/blogger's response to the critics -
Charging a Tesla Model S Might Be Costing More Than You Think - TESLARATI.com
and I agree, the critics went too far the other way, but even the Tesla owner/blogger (and fan) had to agree that Tesla's numbers are just bogus by a wide margin. So let's review the numbers/facts (excuse me for going back-forth on km/miles, but that's how they are reported):
Start with 'Vehicle Mileage” - the Tesla Roadster's 53kWh pack, and 393 km range (EPA) gives 134.86 Wh/km. Tesla exaggerated the 'mileage' by 1.226x already.
Tesla apparently uses an 86.33% number for charge efficiency/losses to come up with 2.18 km/MJ 'Vehicle Efficiency” (110 Wh/km converts to 2.525 km/MJ; multiply by .8633 to get 2.18) . To get a better handle on these numbers, let's use more current Model S Wh/km and loss numbers (the concept is the same, but more/current data is available). The Tesla owner/blogger and others also report ~ 86% charge/standby-loss efficiency on 240V chargers. And this is generous if any significant charge time is done at 110V (according to Tesla, charge efficiency drops to < 73% on 110V, and this does not appear to include the non-charge time standby losses). So take Model S EPA 85kWh/426km = 199.53 Wh/km divide by a generous 86.33% charge/loss factor (assuming no 110V charging) = 231.13 Wh/km. That converts to 1.202 km/MJ, now multiply by Tesla's “Well-to-Station” efficiency of 52.5%, and you get 0.631 km/MJ.
Like miles/gallon, bigger numbers are better. Wait a minute... that makes the Model S
worse than a hybrid (@ 0.64), and only ~ 24% more efficient than even a standard gas engine (@ 0.510). Where did the 'green' go?
But that's not all. In the 'Well-to-station' column, they use Natural Gas to generate the electricity at 52.5% efficiency. Again, some funny assumptions here - the fine print says that is based on “The H-System Combined Cycle Generator from General Electric“ which is among the most efficient type of NG turbine available, and it looks like they are using peak efficiency numbers.
This source:
SAS Output
indicates that NG CC units are running an average of ~ 44.5%, and coal plants run ~ 33.82% (Coal supplies more power on average than NG). What % of NG plants are these high efficiency units? And who says that all the power used to charge EVs comes from NG anyhow? But even giving Tesla the benefit of the doubt on ALL this - take the EIA average number for NG CC units of 44.5% (ignore lower efficiency NG units, ignore lower efficiency coal), and add in the other losses that Tesla does account for (Natural gas recovery @ 97.5%, NG processing @ 97.5%, grid transmission efficiency @ 92% - 97.5% x 97.5% x 92% = 87.46%.), you get 44.5% X 87.46% = 38.92%.
And that puts a Tesla Model S at worse efficiency (0.468 km/MJ) than standard gasoline cars! And that is with lots of assumptions in Tesla's favor!
Sure, when we have an excess of 'clean' energy to feed the added EV demand (when will that be?), things would look better. As I mentioned on another thread, EVs are added demand on the grid, so we really need to be looking at where the
additional marginal energy production comes from (the renewable energy has already been allocated, I don't see where we have any significant 'excess' available to charge EVs). But Tesla's analysis was done to compare today's EV to today's cars (which will also improve in the future). And the actual numbers show that EVs are not green today (and may not be for a very, very long time), and Musk is playing on the general public believing that they are, and feeding that with a chart and talk along those lines. I have a big problem with that. You can have your own opinion, but not your own facts.
I welcome any relevant/documented added info and/or corrections, maybe I made an error or misread something and I'd like to be accurate.
-ERD50