Volt gets 60 mpge combined

http://green.autoblog.com/2010/11/24/2011-chevy-volt-gets-93-mpge-and-37-mpg-rating-from-epa/1#comments
http://nissan-leaf.net/2010/11/24/epa-rates-the-2011-chevrolet-volt-at-60-mpge-cobimed-93-mpge37mpg-with-35-miles-of-electric-range/

35 mile electric range, 37 mpg running on gasoline

Interesting. Why is Volt electricity "$0.11 per kWh" and Leaf electricity is "$0.12 per kWh" for operating cost? That hardly seems fair.

GroundLoop said:

Interesting. Why is Volt electricity "$0.11 per kWh" and Leaf electricity is "$0.12 per kWh" for operating cost? That hardly seems fair.

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That's ok. Ours is .07/kwh.

GroundLoop said:

Interesting. Why is Volt electricity "$0.11 per kWh" and Leaf electricity is "$0.12 per kWh" for operating cost? That hardly seems fair.

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As I mentioned in the "Nissan Leaf gets 99 mpg equivalent" thread it appears that the 12 cents per kW-hr on the Leaf sticker is a typo and should also be 11 cents like the Volt sticker.

100/34=2.941176471 15000/2.941176471=5099.999999286 5099.999999286X.11=560.999999921

Rounded it becomes $561 and that is what is on the Leaf sticker. If they were really using 12 cents it should have been $612 on the sticker.

So it looks like the EPA says the Leaf will go 73 miles on a charge (and Nissan projects 100) and the EPA says the Volt will go 35 miles on a charge on battery only (and GM has said 40).

Anyone understand why the difference in EPA estimate vs. manufacturers claim? Has GM underestimated, Nissan over estimated? Are any of these numbers based on real world tests, or just manufactured based on stated battery capacity and vehicle weight?

I think it's because GM made a last-minute change in battery use. For a year they were saying 40 miles on 8 kWh, which always sounded too good to be true. Now it turns out they've opened up the battery usage range to 12.9 kWh.

(Funny thing - That's about 80% of their total 16 kWh battery capacity. Now, where have I heard that number before?)

planet4ever said:

Now it turns out they've opened up the battery usage range to 12.9 kWh.

(Funny thing - That's about 80% of their total 16 kWh battery capacity. Now, where have I heard that number before?)

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Keep in mind that the 12.9 kWh for a full charge on the Volt is most likely measured at the plug and not the energy that is stored in the battery. Perhaps it really takes 12.9 kWh of energy to put 8 kWh of charge into the battery on the Volt even though I can't imagine it would be that high of a loss.

When I do the math on the Leaf sticker to see how much energy is needed for a full charge it comes out to 99/33.7=2.93768546 73/2.93768546=24.849494949 or about 24.85 kWh. This is very close to the 24 kWh value we have been told. I can see a 0.85 kWh loss for a 24 kWh charge. That sounds like about a 3.5% loss to me.

So it certainly sounds like the Volt is using closer to 12.46 kWh of its battery for a full charge assuming the same 3.5% charging loss.

I would be interested to know the actual charging efficiency of both cars of course.