Submitted to: BioEnergy Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/3/2012
Publication Date: 1/29/2012
Citation: Archer, D.W., Johnson, J.M. 2012. Evaluating local crop residue biomass supply: Economic and environmental impacts. BioEnergy Research. 5:699-712. DOI:10.1007/s12155-012-9178-2.
Interpretive Summary: There is increasing interest in energy production from biomass, including crop residues such as wheat straw and corn stover. Local farmers, biomass industry, and other stakeholders need information on the amount of biomass that a farmer could profitably supply, and potential economic and environmental impacts. This study evaluated biomass production decisions at the field level for a biomass gasification facility in Minnesota. Results show that the some farmers could profitably supply corn stover to the facility at prices of $54 per dry ton. As much as 648,000 tons could be supplied from within a 20 mile radius of the plant at a price of $76 per ton. Results also show that farmers are likely to shift tillage and crop rotation practices in response to increasing biomass price, switching from a corn-soybean rotation toward continuous corn. While biomass harvest could increase soil erosion rates and reduce soil organic carbon levels, changes in crop production practices are shown to at least partially offset these impacts. Transportation costs tend to concentrate corn stover harvest near the biomass facility, which also tends to concentrate environmental impacts near the facility. These results provide farmers and biomass industry with information needed to evaluate the economic viability of using crop residues for energy production and help avoid negative environmental impacts.
Technical Abstract: The increasing interest in energy production from biomass requires a better understanding of potential local production and environmental impacts. This information is needed by local producers, biomass industry, and other stakeholders, and for larger scale analyses. This study models biomass production decisions at the field level using a case example of a biomass gasification facility constructed at the University of Minnesota – Morris (UMM). This institutional-scale application has an anticipated feedstock demand of about 8000 Mg yr-1. The model includes spatial impacts due to sub-field variation in soil characteristics and transportation costs. Results show that the amount of biomass producers could profitably supply within a 32.2 km radius of UMM increases as plant-gate biomass price increases from $59 Mg-1 to $84 Mg-1, with 588,000 Mg annual biomass supply at $84 Mg-1. Results also show that the most profitable tillage and crop rotation practices shift in response to increasing biomass price with producers shifting from a corn-soybean (C-SB) rotation toward continuous corn (CC). While biomass harvest is conducive to increased soil erosion rates and reduced soil organic carbon (SOC) levels, changes in crop production practices are shown to at least partially offset these impacts. Transportation costs tend to concentrate and intensify biomass production near the biomass facility, which also tends to concentrate environmental impacts near the facility.