If biofuels are to be successful, subsidies must exist, says an Iowa State study exploring their future.

Ag economists calculated that to meet federal production mandates, corn will need a 22-78ยข subsidy, biodiesel will need $1.97-2.90 and cellulosic ethanol will need to be subsidized $1.55-2.11. They contend the federal mandates may create more of a food vs. fuel debate, since corn will need a lower subsidy than switchgrass.