A recent study by the Union of Concerned Scientists found that the benefit of driving an electric car such as the Nissan Leaf depends on where you live. The numerical reduction in greenhouse gases depends on how the local electric utility generates its power. If it relies on hydropower, as on the West Coast, then an electric car is a very green way to go. If the utility relies on coal, as in the center of the U.S., then driving an electric car is comparable to a fuel efficient gasoline-powered car such as a Mazda 3. In California, driving an electric car generates greenhouse gas emissions equivalent to driving a car that gets 79 miles per gallon. But in Minneapolis, the electric car is only as good as a car that gets 37 miles per gallon–nothing exceptional. In other words, in Minnesota a hybrid or really efficient gasoline-powered car might be better for the environment than an electric car.