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Abstract: This paper proposes and tests novel supply chain designs for bioenergy and biobased products that result in logistical costs savings of 2–38%. The proposed supply chain design reduces the costs of: (1) purchasing logistical harvesting equipment; (2) operating logistical harvesting equipment; and (3) holding feedstock inventory, by using a multitude of crop types as feedstock, instead of just one, as is common in research and practice today. In so doing, this research challenges the prevalent assumption that monocultures, despite their known environmental concerns, are preferable from a costs perspective. Simulation/optimization is used to test supply chain designs, and then to find the environmental conditions where these new supply chain designs could be most profitably implemented. [Copyright &y& Elsevier]

Abstract: The U.S. Energy Independence and Security Act of 2007 mandates the use, if produced, of 6.06 × 1010 L of advanced biofuels by 2022. The objective of this study is to determine the ethanol price necessary for a biorefinery to breakeven when using switchgrass as the single feedstock to produce ethanol. A holistic model that encompasses acquisition of land use services, feedstock production, harvest, harvest machine investment, feedstock logistics (storage, transportation), biorefinery location and size, and biorefinery investment is constructed and used to determine breakeven ethanol price. The model was solved for each of three biomass to ethanol conversion rates (250, 334, and 417 L of ethanol Mg−1 of biomass) and each of three biorefinery investment cost estimates ($2, $4, and $6 × 108 for a biorefinery with annual capacity of 379 × 106 L). Breakeven ethanol prices ranged from $0.44 L−1 with a conversion rate of 417 L of ethanol Mg−1 and an investment cost of $2 × 108, to $0.72 L−1 with a conversion rate of 250 L Mg−1 and an investment cost of $6 × 108. Improving the efficiency of conversion from 250 to 334 L Mg−1 decreases the estimated breakeven cost by $0. 07 L−1. Improved conversion efficiency results in a reduction of the total quantity of feedstock required and in the cost to deliver feedstock. Most of the cost reduction follows from reductions in land required (rent), and biomass harvest, storage, and transportation costs. [Copyright &y& Elsevier]