National Public Radio: I have never been into cars. I don’t know an oil filter from an air filter. But my 15-year-old Honda is on its last legs, and recently I’ve been curious about alternative fuels. The first mass-produced electric vehicles ever sold in the United States will begin to hit showrooms by the end of this year. The Nissan Leaf and the Chevy Volt already have tens of thousands of pre-orders. Until now, electric cars had been the domain of small groups of tech hobbyists and hard-core …