Letâ(TM)s do a quick back-of-the-envelope calculation, using the Chevy Volt as an example. In electric mode, the Volt gets about 22 kWh / 100 km, (so it is one of the least efficient electric vehicles out there⦠the best ones get 10 kWh / 100 km). Coal power generation produces about 1 kg of CO2 per kWh, so the âoeCO2 efficiencyâ of the Volt on an entirely coal-fed diet is 22 kg CO2 / 100 km.
The closest analog for the Volt that I can find is the Chevy Cruze, which the EPA rated about 9.8 L / 100 km for inner city driving. (Please feel free to correct me if you find a gasoline car which is a closer match for the size / power of the Volt). Burning gasoline produces approximately 2.4 kg of CO2 per L, so the CO2 efficiency of the Cruze is 23 kg CO2 / 100 km. Even given our unrealistic assumption of 100% coal-derived power, the electric vehicle comes out (slightly) ahead.
Keep in mind, coal accounts for only 45% of American electricity, while cleaner-burning natural gas accounts for another 23%. (The remainder comes from nuclear, hydro, wind, etc.) Natural gas produces 0.2 kg CO2 per kWh, as opposed to 1 kg, so in a more realistic calculation the Volt gets about 10 kg CO2 / 100 km, which more than twice as efficient as the gasoline car! The comparison gets even more favorable to electric when you consider other, more efficient electric cars (the Volt is one of the worst).
I should also point out one other way my quick calculation above is biased in favor of gasoline: the CO2 number for electricity includes losses due to transmission and distribution, while the number for gasoline does not (I only counted the CO2 of the gasoline that ends up in your tank.) For a true apples-to-apples comparison, we should include the considerable CO2 emissions that come with refining and shipping petrol.
Iâ(TM)ll admit my numbers are rather simplistic, so if you can point out any errors Iâ(TM)ve made I would welcome the correction. However, it seems to me pretty clear that you have no idea what you're talking about when you say it is "obvious" that electric cars are not greener than their gasoline-burning predecessors.