Switchgrass budget model: An interactive budget model for producing & delivering switchgrass to a bioprocessing plant

Switchgrass has been identified as an attractive biomass crop, but only a limited amount of research has been conducted on commercial production, processing, and delivery of this crop to processing facilities. Therefore, an interactive budget model was developed to estimate delivery costs of switchgrass depending on whether the harvested material was baled, chopped, modulized, or pelleted. The model was then used to examine the effect of yield, hauling distance, and truck capacity on estimated delivery cost. In general, estimated cost was higher for bales and pellets than for modulized and chopped material. As yield increased, cost per Mg decreased, but this effect was substantially reduced above a yield of 16 Mg/ha. Total cost increased linearly with hauling distance, and decreased as truck capacity increased, although this effect was considerably reduced above a capacity of 20 Mg. The model is useful for planning switchgrass supply systems and establishing future research priorities, and can be modified for application to other biomass feedstocks.