It's home-grown, plentiful, and touted as the best way to wean the US off Mideast oil. But there are limits to how far the US can tilt toward a natural gas economy.
Wind power is currently the largest nonwater source of renewable energy in the US, and its use has grown by 350 percent since 2006.
Letters to the Editor for the weekly print issue of March 26, 2012: Two writers argue that an op-ed critiquing electric cars for failing to reduce pollution is unfounded and outdated. Not so, responds the writer, citing another study.