By Jonathan Eisenthal
A farmer may be able to take a ton of biomass off each crop acre.
But what conditions will encourage farmers to take part in harvesting biomass? And how much biomass could we then expect Minnesota’s farm acres to sustainably yield?
Those are the questions being explored by Joel Tallaksen, a scientist at University of Minnesota’s West Central Research and Outreach Center in Morris. His research project, funded by Minnesota Corn Research & Promotion Council, is called “Implications of Corn Producer participation Rates on Stover Biomass Markets” through which he is working to develop a more precise, concrete estimate of how much biomass would be available from Minnesota’s farms, for use in renewable energy and value added products.
Biomass could be used to generate power and serve as feedstock at ethanol and other industrial plants where there is a ready supply of agricultural residue close by. Biomass could also be used to produce ethanol or other value-added products.
Tallaksen plans to survey a cross section of the 6,000 farmer members of Minnesota Corn Growers Association sometime in February or March, and he is hoping for a good response—from both producers who want to harvest biomass and those who don’t—so we can understand that factors affecting the farmers’ preferences.
“If biomass is done right, this could be a significant new revenue stream for farmers, ethanol producers and Minnesota’s rural communities,” said Chad Willis, a farmer in Willmar and chairman of Minnesota Corn Research & Promotion Council.
Farmers are expressing concerns about not wanting to remove biomass from their fields for agronomic and sustainability concerns—the fear that it could reduce soil organic matter too much or lead to soil erosion.
“Our recommendation right now is to harvest biomass on corn acres every second year of corn in a 50/50 corn and soybeans rotation, on good land,” said Tallaksen. “But we have to emphasize the need to check soils to make sure they are healthy. When we conduct our survey, we want to try to figure out where in the state people are more or less willing, and what other factors might be involved—for instance, the age of the farmer, or the amount of land they have could have an effect on their willingness—another key factor would be how much they would profit per ton of biomass.”
National studies of biomass availability, looking at the range of agricultural, forestry and even municipal waste residues, may have overstated the amount that would be available for commercial use, at least initially. Oak Ridge National Laboratory’s “Billion Ton” studies give a general overview, according to Tallaksen, but this previous work may not provide a complete picture for potential investors and entrepreneurs who need a better sense of the supply before building facilities that can use these materials.
One element often left out of the equation is weather patterns, according to Tallaksen. The unpredictable and local nature of weather would have an impact. A very basic analysis of the first snowfall date and when Minnesota’s peak harvest activity happens shows that about one third of the time, the state experiences its first snowfall before harvest is completed. Since biomass would have to come off after the crop, this can present a major problem. Corn can be combined in light snow, but once biomass is wet, collecting and storing it become much more difficult.
At the E3 conference on November 7, Tallaksen presented preliminary work on the issue he has conducted with Michael Reese, but the team looks forward to the MCGA survey to get a more complete picture.