Electric cars still have a carbon footprint when they’re charged on the grid.
But even when their “upstream” electricity comes from coal-fired power plants, they’re still likely to be less polluting than gasoline cars.
The chart below compares the carbon dioxide pollution put out by gasoline-powered cars and trucks compared with EVs charged on the grid in North Texas, where the electricity is generated mainly by natural gas and coal-fired power plants. It shows that tailpipe emissions just aren’t winning this contest.
The chart, based on EPA estimates of the annual carbon dioxide pollution put out by various models, clearly shows that EVs are far less polluting.
And in the case of the least-polluting car, the Leaf, the CO2 emissions are less than half of the EPA’s “average” car. The Leaf turns out to be the lowest-emitting car because it consumes the least amount of energy per output — 30 kWh/100 mi — giving it a combined city/highway MPGe of 114 miles.
MPGe is an equivalency of Miles Per Gallon worked out by EPA so cars can be compared. It helps you see how efficient the Leaf is, at 114 MPGe, compared to say an SUV getting 24 MPG.
Tesla, the other wide ranging EV (with an awe-inspiring range of 265 miles), comes in at 38 kWh/100 miles with its Tesla Model S 85KWhr battery pack, giving it an MPGe of 89.
So the Leaf wins.
Now, if you charged your Leaf, Volt or Tesla on a home charger powered by rooftop solar or on at a house powered completely by wind (which is possible in Texas), your carbon emissions, for driving, drop to zero.
The only greenhouse emissions you could conceivably count against the car would be those generated when the vehicle was manufactured, and those emissions are unavoidable for all models.