From Julian Marshall, an engineering professor at the University of Minnesota, co-author of a study published this week in the Proceedings of the National Academy of Sciences that examines the total environmental cost of various automotive energy sources (story from Associated Press):
“It’s kind of hard to beat gasoline” for public and environmental health,” said study co-author Julian Marshall, an engineering professor at the University of Minnesota. “A lot of the technologies that we think of as being clean … are not better than gasoline.”
If the electricity for an electric car comes from coal, which is still America’s largest source of energy at 39 percent of total energy usage, there are 3.6 times more times soot and smog deaths associated with the electricity generation than those produced by a regular gas-powered car. Electric cars also produce “significantly” more heat-trapping carbon dioxide when coal is used to generate their electricity.
“Unfortunately, when a wire is connected to an electric vehicle at one end and a coal-fired power plant at the other end, the environmental consequences are worse than driving a normal gasoline-powered car,” said Ken Caldeira of the Carnegie Institution for Science, who wasn’t part of the study but praised it.
The news is not all bad for electric vehicles. When natural gas (27 percent of America’s energy usage) is used to generate the electricity, it produces one-half the air pollution related health problems and mortality as gas-powered cars do, and when the power comes from wind (4.13 percent), water (7 percent), or waves (negligible), they produce only one-quarter the health problems and mortality. So the next time a smug electric car owner brags about how much they are doing for the environment, ask him or her where the energy used for their wonder vehicle comes from.
