June 22, 2011. The U.S. would have to use 13.2 billion gallons of mostly corn-based ethanol in 2012 as mandated by Congress, the Environmental Protection Agency proposed, but the agency slashed the target for advanced cellulosic ethanol output. The EPA proposed cutting the amount of cellulosic ethanol, which is made from switchgrass and other agricultural waste, that must be produced next year to between 3.45 million and 12.9 million gallons from the original goal of 500 million gallons. The EPA sets the renewable fuel standard every year as required by Congress, based on gasoline and diesel demand projections from the U.S. Energy Department.