The use of edible feedstocks in energy production has caused significant controversy.  Wide fluctuations in oil prices and the quest for the reduction of carbon emissions have contributed to making many feedstocks, such as corn, soybean, rapeseed and palm oils, viable energy solutions.  In addition, many governments have enacted incentives for renewable energy (i.e. the U.S. $1 per gallon subsidy for blending biodiesel).  The result has been higher food prices.

According to the United States Department of Agriculture, in 2007 the U.S. used 18 to 20 percent of its total corn crop for the production of ethanol, and in 2008 that was predicted to jump to 25 percent. And that increase, says Marshall Martin, an agriculture economist at Purdue University, "is the main driver behind the price increase for corn".

The jump in corn prices is already affecting the cost of food. The most notable example is in Mexico, which gets much of its corn from the United States, the price of corn tortillas doubled, according to press reports, setting off large protest marches in Mexico City. It's almost certain that most of the rise in corn prices is due to the U.S. ethanol policy, says David Victor, director of the Program on Energy and Sustainable Development at Stanford University. As a result, all edible feedstocks are falling out of favor and more research is going into crops that can be converted to energy without competing with food.