From the New York Times Green, Inc. blog:
In the latest installment of the debate over the emissions impact of corn-based ethanol, researchers from the University of Minnesota and other institutions found that corn ethanol is worse for health and the environment than regular gasoline, and far worse than cellulosic ethanol.
The study, published in the Proceedings of the National Academy of Sciences, looked at various types of fuels’ climate and health costs — defined as a combination of health costs from the emission of fine particulate matter, and climate costs from issues like mitigation, carbon capture and the damage from sea-level rise or crop loss.
The findings identified corn ethanol (corn is the main feedstock for ethanol produced in the United States) as more “costly” than cellulosic ethanol or even regular gasoline, though the range of cost estimates was wide and dependent on a large number of variables.