Electric vehicles can be an effective way to reduce pollution from transportation and limit global warming.

But in most parts of the U.S., the electricity used to charge EVs is still dominated by fossil fuels.

“The total emissions from electric vehicles do depend on where the electricity comes from,” says David Reichmuth of the Union of Concerned Scientists. “What I’ve been doing in my research is comparing the global warming emissions from using an electric vehicle to that of a gasoline vehicle.”

In addition to the tailpipe emissions from gas-powered cars, Reichmuth considered the impacts of extracting oil, getting it to a refinery, making gas, and transporting it to gas stations.

He compared that to the climate cost of generating the electricity used to charge EVs, which still primarily comes from producing and burning fossil fuels.

He says the results are clear. Even with the current electricity mix in the United States, driving using electricity is cleaner than gasoline.

And Reichmuth says that as the country transitions from fossil fuels to clean energy, electric cars will have lower emissions in each year that goes by.

“So effectively, electric cars already on the road are going to get cleaner over time as we clean up the grid,” he says.

Reporting credit: Stephanie Manuzak/ChavoBart Digital Media