Residual biomass energy sources – such as manure and corn “stover” (cobs, leaves, etc.) or other byproducts of farming or other activities – could be an important energy source for the U.S. Midwest, according to a report sponsored by the Chicago Council on Global Affairs.
Harnessing the Power of Biomass Residuals: Opportunities and Challenges for Midwestern Renewable Energy is partly based on the hope that such residual biomass might be less controversial than biofuels, which raise environmental concerns or issues related to competition with food needs.
Among the study’s findings are that ecologically sustainable residual biomass could produce 17 percent of regional gasoline needs or 14 percent of electricity requirements, that these resources are concentrated in certain areas, that a broad “landscape-based” framework should be used to evaluate the costs and benefits of bioenergy use, and that non-energy benefits may be as important as energy benefits in using these resources.
The report also found that technology now exists to produce bioenergy from animal manure, while technology to produce ethanol from corn stover and similar feedstocks is not yet ready for the market.
In addition, it said, most bioenergy systems using residuals are not competitive, and subsidies and other public actions will be needed if they are to become practical.
The study recommended that manure resources be utilized by increasing farms’ use of anaerobic digesters – which produce bioenergy while helping to eliminate odors and providing other benefits – and developing watershed-based nutrient trading systems.
It also called for regional corn farmers to be prepared to participate in a cellulose market by increased research on stover harvesting and how different tillage systems affect grain and stover production.
Finally, it recommended that a landscape-based perspective be used to analyze biofuel feedstock potential.