How Green Is Your Electric Car?

(Bloomberg)The biggest selling point of the electric car has long been the fact that it’s emissions-free. Turns out that’s not exactly true.

Trading in your gasoline-guzzling car for an electric vehicle is a lot like shifting the emissions from an exhaust pipe to a power plant. EVs run off electricity, and that electricity — unless you’re lucky enough to live in a place like Norway — is coming from a mix of emissions-intensive fossil fuels, nuclear and, to a lesser extent, renewable energy. 

So exactly how green your EV is depends on where you’re plugging it in. An electric car in Norway is probably the closest thing you’ll get to a true zero-emissions vehicle—because the European country draws almost all of its electricity from hydropower plants.

But most of the world’s biggest EV markets rely largely on fossil fuels. China, by far and away the largest market for electric vehicles, depends on emissions-intensive coal. America’s hooked on natural gas. The U.K. and France benefit from emissions-free nuclear power.

And that’s just the start. Even regions within a country rely on wildly different resources for power. Take the U.S., where California gets virtually none of its power from coal and Texas relies on the rock for more than a quarter. 

Also, not all fossil-fuel plants are created equal. Some states are stricter about the emissions these generators can spew than others. That’s why the emissions factor for power generation in cities across the U.S. can vary so greatly. 

Take into account power-plant emissions, and your electric car could easily be responsible for more than 100 grams of carbon-dioxide emissions for every mile driven. Not surprisingly, an electric car in China accounts for more than double the emissions than one in the U.K. That's still better than the average internal combustion engine.

Look on the bright side: Driving an electric car is still better for the world than chugging around in a gasoline-burning one. According to Bloomberg New Energy Finance, running off electricity was 39 percent cleaner than using internal combustion engines in 2016. And that gap is expected to widen to 67 percent by 2040 as solar and wind power keep taking on a bigger and bigger share of the world’s power mix.