Coal plants provide more than half of America's electricity.
At the same time, they are the nation's largest stationary source of air pollutants such as sulfur dioxide and nitrogen oxide, which cause smog and acid rain. Power plants release one third of the nation's carbon dioxide emissions, whose build-up worldwide, scientists believe, is causing global warming, hotter summers and more violent weather patterns. To meet peak demand during heat waves, our utilities fire up older, dirtier coal plants that add even more to air pollution. In the United States, from June 1998 to July 1999, the wind industry installed a total of 1,073 MW in new wind turbines and generating equipment. These amounts would have been emitted if instead the average U.S. utility fuel mix had been used to produce an equivalent amount of electricity.