Last week, investment bank Morgan Stanley was quoted as claiming electric vehicles are responsible for more global warming emissions than gasoline cars. The firm’s report says Tesla isn’t a ‘green’ company because of this (incorrect) conclusion. There are likely plenty of reasons to invest in the electric car and solar panel maker, and certainly many reasons not to bet on Tesla, but the false claim of dirty cars isn’t one of them.
Why did Morgan Stanley get the wrong answer? It’s hard to say because no underlying data is shown to back up Morgan Stanley’s assertions, so I can’t check their calculations. However, you are welcome to inspect ours; we wrote a report in 2015 comparing the emissions of electric cars and gasoline vehicles, and recently updated it with new electricity generation data.
What are the global warming emissions from electric cars?
The emissions that result from using an electric vehicle (EV) depend on part on where the vehicle is recharged, as electricity generation varies significantly across the United States. Based on where EVs have been sold so far, the average electric car generates global warming emissions equal to a 73 MPG gasoline car. Overall, over two-thirds (70 percent) of Americans live where driving an electric car would result in lower global warming emissions than even a 50 MPG gasoline car.
Manufacturing emissions are small compared to savings during use
Even when considering the emissions from the manufacture of the EV’s battery, EVs over their lifespan result in significant global warming emissions savings. Over the lifetime of a car the size of the Tesla Model S, the emissions savings are about 53 percent, when compared to a similar gasoline car.
Electricity is getting cleaner, making EVs better over time
Very few details are given in the article about Morgan Stanley’s analysis, however one of the few statistics given (regarding the fraction of electricity from fossil fuel in the U.S.) is wrong.
Nationally, we currently derive about 65 percent of electricity from fossil fuel and only about 31 percent from coal, down from 50 percent in 2006.
Both fossil-fueled electricity and coal generation have declined substantially over the last decade, making driving EVs cleaner. And as we increase the amount of renewable electricity in the U.S., driving on electricity can be even cleaner.