Ethanol reduces greenhouse emissions by almost half over gasoline

Jan 16, 2017

The E Energy ethanol plant near Adams, Neb., processes about 50 million gallons of ethanol per year.
Credit Grant Gerlock / Harvest Public Media

A new U.S. government study claims ethanol is better for the environment than most scientists initially expected, boosting an industry that is a boon to Midwest farmers but challenged by many environmental groups and the oil industry.

The report from the U.S. Department of Agriculture says corn-based ethanol reduces greenhouse gas emissions by 43 percent over gasoline and suggests that emissions could decline further with more no-till farming, more cover crops and better fertilizer management. (PDF) The U.S. Environmental Protection Agency in 2010 projected corn ethanol would reduce emissions by about 20 percent by 2022.

In recent years, millions of acres of pasture and forest have been plowed up to raise corn. Many environmental groups say that cancels out the greenhouse benefits of ethanol. This report argues corn ethanol bears less responsibility for that expansion.

The future of the Renewable Fuel Standard, the 2007 law that governs how much ethanol must be blended into the U.S. gasoline supply, is unclear under a President Trump. Oklahoma Attorney General Scott Pruitt, Trump’s nominee to head the EPA – the agency that oversees the RFS – has criticized the RFS in the past. On the campaign trail, however, Trump generally pledged support for the ethanol industry.

Iowa is the nation’s top ethanol producing state, followed by Nebraska and Illinois.