Mother Earth News article "Why EV's are Cleaner". http://www.motherearthnews.com/green-transportation/electric-cars-zm0z11zsto.aspx Chart from article comparing EV carbon footprint by region of country. http://www.motherearthnews.com/multimedia/image-gallery.aspx?id=2147492318&seq=1 Chart from article comparing carbon footprints of EV's, hybrids, and conventional cars. http://www.motherearthnews.com/multimedia/image-gallery.aspx?id=2147492318&seq=2 From the charts, it looks like any gasoline car that gets over 50mpg in the Mid-west or South will have a smaller carbon footprint than a Leaf-sized EV operating in that region. In California, the gas car would have to get over 75mpg to reach carbon foot print equivalency.