Impacts of Different System Variables on Delivered Price of Switchgrass Biomass.

The objective of this study was to determine the relationship between several system variables and the delivered price of switchgrass biomass to a processing plant. To conduct the study a spreadsheet model previously developed from commercial scale field operations involving harvesting and hauling switchgrass to a processing plant was used. The variables studied were size of the processing plant, proportion of land planted with switchgrass, land rental rate and labor wage rate. Ranges in these variables that were considered were 500 – 2,000 tons of biomass per day for plant size, 2 – 50% for proportion of land in switchgrass, $0 - $150/acre/yr for land rental rate, and $12 - $24/hr for labor rate. Each of these variables was systematically varied in the model, and the related changes in delivered cost were recorded. As the plant size increased, delivered cost of switchgrass increased because the transportation distance also increased, but this relationship was not linear. As the proportion of land in the biomass supply area planted to switchgrass decreased, the plant must access biomass from further distances, again resulting in a non-linear increase in delivered cost. Delivered cost of switchgrass increased linearly with increases in land rental and labor rate.