For those who care about the environment and keeping their driving footprint small, one of the most compelling selling points for electric cars is that your car gets cleaner over time—because the electricity you’re plugging into, from the power grid, is being weaned off coal and toward cleaner and more sustainable sources.

This isn’t just some theoretical, based on projections about the greening of our power grid. It’s happening.

Average EV - gasoline mpg equivalent - UCS, 1/2020

According to the latest "well-to-wheels" data from the Union of Concerned Scientists, 94 percent of Americans now live in a place where, based on their local grid, driving an electric vehicle produces less emissions than driving a 50-mpg gasoline car.

When the organization first made this assessment, in 2012 (of 2009 utility data), it found that to be the case for 45 percent. And over that time, the fraction of U.S. electricity from coal has gone from 45% to 28%, while the fraction of electricity from wind and solar has gone from 2% to 8%.

EV progress, 2009-2018, UCS 2/2020

The calculations from UCS include power-plant emissions plus the emissions from the production of coal, natural gas, or other fuels used for power generation.

In its January 2020 update, UCS tallied the emissions from power plants over the 2018 calendar year. UCS notes that power-plant emissions in the U.S. fell more than 5% from 2016 to 2018, from less coal and more natural gas, wind, and solar. Coal plants were retired at a record pace in 2019, so we would expect the grid is even quite a bit better today than this represents.

One other valuable takeaway is that there’s no longer any quibbling over outlier regions. The latest data confirms that the average EV is responsible for fewer global-warming emissions than the average new gas car anywhere in the U.S.

Most efficient EV - gasoline mpg equivalent - UCS, 1/2020

The organization also noted that versus two years ago, the average efficiency of electric vehicles has improved—especially considering Model 3 sales add up to more than a third of all EV sales. The 2020 Tesla Model 3 Standard Range Plus is the most efficient car on the market; and in California, it's the equivalent of a 161-mpg gasoline car—with one-fifth the global-warming emissions of the average gasoline car and more than 60% less than the average gas car.