content: It's hard to get solid numbers on this. US coal power plants generate about 1.09 kWh per pound of coal Burning 1 pound of coal generates on average of 2.19 pounds of CO2 So that gives us 2.19/1.09 = 2.0092 pounds of CO2 per kWh Tesla claims 0.320 kWh/mile of energy (85kWh/265 miles) which seems to jive with real world numbers reported by users. Charging efficiency is hard to pinpoint but 90% is probably doable (I've seen Tesla claims of 93%) Assume 90% efficiency for the electrical grid  (US average is actually 95.3%) Which gives us 0.320/0.9/0.9 * 2.19/1.09 = 0.7937 pounds of CO2/mile Burning gasoline generates about 19.6 pounds of CO2 per gallon A car that gets 35 miles per gallon then produces 1/35 * 19.6 = 0.56 pounds of CO2 per mile A car that gets 25 miles per gallon produces  1/25*19.6 = 0.7840 pounds of CO2 per mile So on the surface a car that gets more the 25 miles per gallon should produce less CO2 emissions per mile than an electric car using power generated solely by coal.   However the return on energy investment for gasoline is about 20% worse than coal (it requires more energy to produce 1kWh of gasoline vs 1kWh of coal).  Assuming that energy comes from fossil fuels as well it bumps the carbon out of the gasoline cars 20% so you would need a car that gets ~ 30miles/gallon to match the Tesla.  But then you could argue you need to include the energy used to produce the battery packs, etc, etc. The real answer though is not to use coal to generate your electricity.  China is currently at ~70% coal but is actively pursuing Nuclear, Wind, Hydro and  Solar generation.  Even at 70% coal production this pushes the electric equation to the better side.