Credit: Charles Dharapak/Associated Press

Few things prompt Washington policymakers to forget their professed belief in the efficiency of free markets faster than $100-a-barrel oil prices--or even the threat of them. In one of the most notable recent examples, as the price of crude oil edged toward the $100 mark late last year, the U.S. Congress passed, and President Bush quickly signed, the Energy Independence and Security Act of 2007.

Among its various provisions, the energy bill prescribes a minimum amount of biofuel that gasoline suppliers must use in their products each year through 2022. The new mandates, which significantly expand the Renewable Fuels Standard of 2005, would more than double the 2007 market for corn-derived ethanol, to 15 billion gallons, by 2015. At the same time, the bill ensures the creation of a new market for cellulosic biofuels made from such sources as prairie grass, wood chips, and agricultural waste. The standards call for the production of 500 million gallons of cellulosic biofuel by 2012, one billion gallons by 2013, and 16 billion gallons by 2022.

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