By Brad Berman · May 31, 2017





Electric-vehicle critics are fond of explaining that the energy to power an electric car has to come from somewhere. They make the argument that EVs plugged into the grid in coal-dependent regions of the US aren’t nearly as clean and green as you might imagine. The Union of Concerned Scientists went back to the drawing board with new EPA data on emission from electricity generation and today published its findings: For more than 70 percent of Americans, driving an EV results in fewer emissions than a 50-mpg gas-powered car.

Why can’t the UCS make this claim for all Americans? Well, the cleanliness of your EV depends on the emissions produced when generating electricity in your region. Some analysts refer to this factor as “moving the emissions upstream.” While it can be difficult to pinpoint the exact green-ness of your regional or local electricity—and therefore your electric vehicle—what can be shown is that the US electrical grid is getting greener over time.

Using data from 2012, only nine of 26 regions in the US were designated as “best” for global warming emissions. But based on data available in 2017, there are now 19 regions in the “best” category. The UCS states: “For example, the Northern Midwest region that includes Minnesota and Iowa improved from 39 mpg equivalent to 54 mpg and Eastern Wisconsin also jumped from ‘good’ at 40 mpg to our ‘best’ rating with emissions equal to 52 mpg gasoline cars.”

Keep in mind that the average new gasoline vehicle in the US is rated at 25 mpg. For the average American, transportation makes up about a third of all household global warming emissions.

Critically, if you look at the regions where most electric cars have been purchased to-date, the average US electric car produces emissions equivalent to a hypothetical gasoline car achieving 73 mpg. (It’s hypothetical because no gas car on the market can achieve 73 miles per gallon.) If you are driving an electric car in California—where about half of US electric car drivers live—your car represents global warming emissions equal to a 95-mpg car.

Clever anti-EV advocates might argue that manufacturing the batteries, and other electric car components have a big environmental impact. They are only partially correct. Yes, there are emissions and other impacts from making an EV, but according to the Union of Concerned Scientist, those impacts are only 15 percent higher than gas cars—a minor disadvantage that is recouped by eco-savings that accrue on the road in about six and 12 months depending on the model and the region. (EVs don’t have tailpipes.)

What’s the equivalent mpg of your EV based on your region’s electricity? Find out by using the Union of Concerned Scientists’ “How Clean Is Your Electric Vehicle?” online tool.