Land requirements, feedstock haul distance, and expected profit response to land use restrictions for switchgrass production

Energy crop production has been proposed for land of poor quality to avoid competition with food production and negative indirect land use consequences. The objective of this study was to determine the land area requirements, biomass transportation distance, and expected profit consequences of restricting switchgrass biomass production, for use as biofuel feedstock, to marginal land relative to unrestricted land use. The USA soils capability classification system was used to differentiate between high quality land and land of marginal quality. Fifty years of historical weather data were used in combination with a biophysical simulation model to estimate switchgrass biomass yield distributions for land of different quality for counties in the case study region. A mathematical programming model was designed and solved to determine the economic consequences. For the levels of biofuel price considered ($0.50, $0.75 and $1.00/L), and a 262.5ML/year biorefinery modeled, restricting land use to marginally productive capability Class IV soils, increases the quantity of land optimally leased by 42 to 52%; increases biomass trucking total transportation distance by 115 to 116%; and reduces the expected net returns by $11 to $15M/year compared to when land use is unrestricted. In the absence of government restrictions, for-profit companies are not likely to limit energy crop production to land of marginal quality.