Electric Vehicles: Coast to coast, but will they impact emissions?

This week was a milestone in electric vehicle adoption and infrastructure in the US - a father-daughter team completed the first crosscountry roadtrip in a Tesla and it cost them $0 to recharge. What a bargain! Tesla Motors plans to expand their recharching network, so that future continental treks may take a more direct route.  

So as electric vehicles are slowly becoming more mainstream, the question is what impact will they have on greenhouse gas emissions? A paper recently presented at the TRB Annual Meeting looks at regional impacts in California.  Another recent study from NC State questions the impact electric vehicles have on emissions at all. Samaneh Babaee, Ajay S. Nagpure, and Joseph F. DeCarolis ask, "How Much Do Electric Drive Vehicles Matter to Future U.S. Emissions?". Their answer: probably not much given the emissions produced by electricity sources.