Plug in

As Leta likes to remind me, the carbon footprint of an electric vehicle (or anything else powered by mains electricity, for that matter) depends on the underlying energy source used to produce the electricity, be it solar or nuclear or coal. Paul Stenquist previews an upcoming report from the Union of Concerned Scientists on the greenhouse gas impact of pure electric automobiles (Chevy Volt, Nissan Leaf) across the country.

The study translates the effect into an apples-to-apples, miles-per-gallon comparison to conventional cars. Since cities in the Great Plains and upper Midwest get much of their electricity from CO2-spilling sources, driving an electric car charged up in the middle of the country is no better than driving an gasoline-powered econobox that gets 35 MPG. By comparison, in hydro-dependent southeast Alaska, you’d have to drive something that gets 112 MPG to best an electric vehicle.