The days of bio-fuels, at least as we know them, are numbered. In the wake of global shortages of food and increasing doubts about sustainability, the wisdom of promoting bio-fuels as an environmental panacea is facing scrutiny. Until now, conventional wisdom has seen bio-fuels as similar to ethanol, a renewable and environmentally-friendly alternative to petroleum. Their use has gained widespread support among a diverse coalition.
Democrats like them because of their green reputation. Republicans (and Democrats, for that matter) like them because they promise the possibility of energy independence. Farmers like them because they increase the demand