If the Fuel Source Ain't Clean, Your Electric Car Ain't Green
A host of factors determine the role of electric and hybrid cars in reducing greenhouse gas pollution, such as whether coal is their ultimate fuel source. David Biello reports
By David Biello
SUBSCRIBE TO 60-Second Earth
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
As Tesla prepares to begin selling its Model S in smog-ridden China, the question is: do electric cars reduce air pollution? And the answer is: it depends.
That on-the-one-hand-yes-but-on-the-other hand-no conclusion comes from a study predicting the impacts of electric cars in the U.S. to 2050. It's in the journal Environmental Science and Technology. [Samaneh Babaee, Ajay S. Nagpure, and Joseph F. DeCarolis, How Much Do Electric Drive Vehicles Matter to Future U.S. Emissions?]
The reason it depends is that we don't know the future. Will batteries be cheap? Will the U.S. have a law limiting carbon dioxide? Which will cost less: oil or natural gas?
Depending on the answers, electric vehicles and hybrids might not reduce air pollution at all. They could even make it worse.
Researchers ran 108 different computer models of how driving might change in the next few decades. And it turns out the key to reducing air pollution isn't how many electric cars there are. What matters is whether there are regulations in place to mandate reductions in CO2 and other pollutants.
As it stands, battery cars that run on electricity from burning coal can be more polluting than cars that get good mileage on gas. And that's why a Tesla in China, where most electricity comes from coal, is no zero-emissions vehicle.
—David Biello
[The above text is a transcript of this podcast.]
Subscribe to Support Independent Journalism
Great science journalism requires human expertise, time, effort and creativity. And it costs money. That’s why I and the journalists here at Scientific American hope you’ll join our community.
When you subscribe, you are supporting staff and freelance journalists who are passionate about telling science stories that are true, important and compelling. Our editors and reporters are often experts in their fields, which means they understand the nuances of big discoveries and can untangle the breakthroughs from the hype. With a subscription, you are also supporting rigorous fact-checking to ensure the words we publish are precise and accurate. And you’re supporting original illustrations, graphics and photos that bring you closer to an advanced laboratory, an ice sheet in Antarctica or a space mission in orbit. You’re helping us craft other types of high-quality journalism as well: Our newsletters are carefully written, edited and curated by staffers you have or will come to know and love. Our Science Quickly podcast is based on original reporting, collaboration with editors and scientists and exacting production.
Subscriptions keep this engine running so we can continue to deliver thoughtful, rigorous and independent science journalism to you. In an era of viral misinformation, this work is crucial. If you value what we do, I hope you’ll consider joining us as a subscriber
