Coal is the world's most abundant fossil fuel and has long been considered the cheapest for electric power generation. Demand, particularly in fast-developing Asian nations, is outpacing production and driving prices to new highs. Coal producers expect use to increase as energy demand expands. But many governments are trying to increase energy efficiency and limit use of coal, whose carbon dioxide emissions contribute to climate change.
GRAPHIC: Dita Smith, Laris Karklis and Rob Thomason - The Washington Post - March 20, 2008