A new report shows that current corn-ethanol systems are much more energy efficient and have a much greater potential to reduce greenhouse gas emissions than previously published studies.
The report, “Improvements in Life Cycle Energy Efficiency and Greenhouse Gas Emissions of Corn Ethanol” was just released by the University of Nebraska-Lincoln’s Nebraska Center for Energy Sciences Research and published in Yale’s Journal of Industrial Ecology (JIE).
Compared to the earlier studies, UNL’s research team utilized more recent data that better represent how the corn ethanol industry is currently performing. In particular, updated values were used for: (1) yields and inputs required for corn production, (2) energy requirements in the ethanol plant, and (3) a more accurate representation of how co-products are used in livestock diets.
As a result, the report concluded that “Direct effect GHG emissions were estimated to be equivalent to a 48% to 59% reduction compared to gasoline, a twofold to threefold greater reduction than reported in previous studies.” The report also found that the eight corn-ethanol scenarios had net energy ratio (NER) values from 1.29 to 2.23, meaning ethanol returned 29 to 123 percent more energy than was required for its production.