- Oct 14, 2011
How gas cars use more electricity to go 100 miles than EVs do
EVangelist Peder Norby, who has been having more fun driving and writing about his Mini E than anyone at BMW probably thought possible, recently wrote a most interesting post comparing electricity usage to produce gasoline to the electricity needed to drive an electric car. The short version: "It takes more electricity to drive the average gasoline car 100 miles, than it does to drive an electric car 100 miles."
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. Here are some numbers (get more details in Norby's post).
There is no exact calculation for how much electricity it takes to drill, transport and refine a gallon of gasoline, but the accepted amount is around 8 kWh. So, for 8 kWh, you can go around 22 miles (using the U.S. average; we know you can go over twice that if you drive a Toyota Prius). That means that a gasoline car uses just under 40 kWh to go 100 miles. An EV, on the other hand, uses around 30 kWh to go 100 miles (given 3.3 miles per kWh, which is on the low side for some cars). Even if the exact numbers need to be shifted a bit one way or the other, we're just comparing electricity use here – not the petroleum that needs to be factored in for the ICE vehicle. So, if we were able to magically use all the electricity that is currently spent to give us gas and shove it into automotive battery packs instead, we'd use less energy and no gasoline. So much for the long tailpipe argument. Nissan sometimes uses this argument when advertising the Leaf, but it's not a commonly used statistic. We wonder why.