I'm not sure how much I can trust that document. It's written by some academics, they might or might not have an agenda. Here's a study done by the USDA, publi

I'm not sure how much I can trust that document. It's written by some academics, they might or might not have an agenda. Here's a study done by the USDA, published in 2016 and describing the state of the affairs in 2015 https://mnbiofuels.org/images/2015EnergyBalanceCornEthanol.pdf https://mnbiofuels.org/images/2015EnergyBalanceCornEthanol.p... Bottom line: ignoring any carbon credits, the return on energy using the existing facilities in Iowa is 2.3 (page 14, bottom of 3rd column).