Using coal to make electricity accounts for about a third of America's carbon emissions. As a result, tackling emissions from coal-fired power plants represents our best opportunity to make sharp reductions in greenhouse gases. Fortunately, the United States already has the technology to do that. Unfortunately, right now the country is addicted to coal, a cheap, abundant power source. Burning coal produces more than half the country's electricity, despite its immense human and environmental costs. Air pollutants from coal-fired power plants cause somewhere between 20,000 and 30,000 premature deaths in the United States each year. Besides, fifty tons of mercury are pumped into the atmosphere annually from coal plants. In addition, the extraction of coal, from West Virginia to Wyoming, devastates the physical environment, and its processing and burning produce gigantic volumes of waste.