Last week's heat wave prompted another eruption of that perennial question: Won't electric cars that recharge from grid power overload the nation's electricity system? Or put more bluntly: Will electric vehicles bring down the U.S. power grid?

The answer, equally bluntly, is: No. They won't.

Study by Unlikely Partners

A comprehensive and wide-ranging two-volume study from 2007, Environmental Assessment of Plug-In Hybrid Vehicles, looked at the impact of plug-in vehicles on the U.S. electrical grid. It also analyzed the "wells-to-wheels" carbon emissions of plug-ins versus gasoline cars.