Explainer: Are electric vehicles really better for the environment?

This chart below plots dozens of vehicles against greenhouse gas emissions. The black dots are gasoline vehicles; The pink and red dots are hybrid vehicles; The yellow dots are battery electric vehicles. The dotted lines are where the U.S. wants vehicle carbon emissions to be by 2030 and 2040…

But the vehicle itself is not the entire story.

It also depends on where you’re getting your charging power from. If you’re plugging your electric vehicle into a coal-heavy power grid, it can actually be worse — especially if you’re driving a hybrid.

“Coal tends to be the critical factor,” said Jeremy Michalek, a professor of engineering at Carnegie Mellon University told the New York Times. “If you’ve got electric cars in Pittsburgh that are being plugged in at night and leading nearby coal plants to burn more coal to charge them, then the climate benefits won’t be as great, and you can even get more air pollution.”