Try googling on something to the effect of "Pimental study debunked". As it turns out, Professor Pimintal has no idea how corn is raised or what it's used for.
Just like our whole basis for poo poing freon r-12 was based on bogus research at USC by 3 "acedemic" idiots sponsored by Du Pont.
Gee I wonder who debunked it? I wonder if it's on Ethanol.org?