20 companies that lost the most

Alpha Natural Resources, one of the nation's largest coal companies, was left out in the cold this year. A mild winter drove down heating costs and more users switched from coal to natural gas -- which is not onlycleaner burning, but super cheap. In a recent earnings call, Alpha's CEO said that the ultracheap gas prices of 2011 effectively capped the cost of coal at a level too low for the company to turn a profit in a large swath of the country.

In response, the company cut production by some 4 million tons in Central Appalachia. Alpha's big $677.4 loss for 2011 is thanks in large part to a $745 million write-down due to "changes in market outlook," including expected lower production. Still, last year's revenue was at record levels, thanks in part to the $7 billion acquisition of coal mine operator Massey Energy. Plus, coal bulls say natural gas conversions may taper off as the country gets to the point where every household that can switch or will switch already has.

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