Studies remeasure corn-based ethanol's impact, potential

By Jerry W. Kram | January 03, 2009
Corn-based ethanol production has often been and will likely continue to be scrutinized. Recently, two studies commissioned by the Illinois Corn Marketing Board updated corn-based ethanol's energy balance and evaluated global corn supply, while another study examined what would happen if corn-based ethanol plant construction levels off.

To determine ethanol's energy balance, Steffan Mueller, principal research economist of the Energy Resources Center at the University of Illinois at Chicago, conducted a life cycle analysis of Illinois River Energy LLC, a 50 MMgy ethanol plant near Rochelle, Ill. Using surveys of local corn growers and USDA data, he concluded the facility had 21 percent less of a global warming impact (GWI) than the standard value for existing ethanol plants, and 40 percent less GWI than gasoline from petroleum. "We wanted to dig deeper and actually survey the corn producers who are providing corn to the plant, which led us to get involved in the land-use issue," said Rodney Weinzierl, the board's executive director. "We think that as you get outside the corn industry, a lot of people may not realize we are continuing to increase yields and use fewer inputs to do it."

Ross Korves, economic policy analyst at ProExporter Network, examined the ability of U.S. corn growers to supply adequate grain supplies to the feed and fuel industries from 2016 to 2030. Corn yields steadily increased over the past 60 years as fertilizers, pest control chemicals and genetically modified corn varieties were adopted by corn growers. By tracking average yield growth since 1990, Korves concluded that by 2030, corn farmers could support the production of 36 billion gallons of ethanol per year on the same number of acres, plus meet increased demand for feed, food and industrial products.

Robert Wisner, a biofuels economist for the Agricultural Marketing Resource Center at Iowa State University, also explored future corn supply, except he used the assumption that corn-based ethanol production would plateau in the next few years. He found that a leveling off of ethanol production plus increased corn yields could ease corn supply tightness by the 2011-2012 marketing year. Since ethanol demand is expected to increase due to the federal renewable fuels standard. He concluded that production capacity, including plants currently under construction, will fall 15 percent short of the target for corn-based ethanol in 2015. This could raise ethanol prices and lead to an increased use of corn for ethanol.