Ethanol is a loss. You lose 55,000BTU's per gallon when everything is taken into account. It takes roughly 26.1lbs of corn to make it. Which with the average production per acre means 1k acres would make rougly 250k gal. However ethanol plants use TONS of water.
It sounds good in GM commercials ect but in reality it's not worth the paper it's written on. THe only place where ethanol becomes efficient is when it's produced from human waste which about 60% can be made into it.