Biofuels are at a crossroads. According to the International Energy Agency, global biofuels production has grown more than sixfold over the last decade, yet biofuels still account for just 3 percent of all road fuel energy. While it may seem preferable, in theory, to make fuel from plant matter rather than oil, the reality of producing biofuel comes with its own costs and questions. (For more about biofuels, see "Biofuels at a Crossroads.")
Corn-based ethanol, the world's dominant biofuel, raises land, food, and water issues associated with growing more crops for fuel feedstock. (See related story: "Drought Withers U.S. Corn Crops, Heats Debate on Ethanol.")
There has been a great deal of investment and hope placed in next-generation biofuels—cellulosic ethanol and other advanced plant- and waste-based fuels that could displace gasoline and diesel fuel in a big way without the resource constraints of ethanol. (See recent related stories about fuel from whisky and microbes.)
But advanced biofuels have not scaled up as quickly as many have hoped. In the United States, for example, there are moves to repeal or scale back a mandate requiring oil refiners to blend increasing amounts of biofuel into the U.S. transportation mix. Domestic production of cellulosic biofuel has not met the government's projections, and enthusiasm for continued ethanol subsidies is low.
Should we continue to invest in biofuels, despite what many view as slow progress so far, and the criticism that the business cannot stand on its own without government subsidies?