Optimal Corn Stover Logistics for Biofuel Production: A Case in Minnesota

Abstract

Logistics management is one of the key hurdles for using corn stover as a feedstock for ethanol production. This article presents a model and its application to compare the costs and CO2 emissions of three corn stover transportation options in the state of Minnesota: truck, rail, and pipeline systems. The corn stover production potential for 53 corn-producing counties in Minnesota is mapped, and potential corn stover storage facilities are located along the railroad system based on regional corn stover production potential. An optimization model was constructed and populated to minimize transportation needs between the storage locations and potential conversion facilities. Because feedstock transportation distance and associated CO2 emissions depend on the number of biorefineries, we varied the number from 1 to 215 and identified optimal locations sequentially at the minimum transportation distance between storage locations and a given number of biorefineries. Using the minimum-distance biorefinery locations identified for each given number of biorefineries, the CO2 emissions associated with corn stover transportation and the total costs were calculated. The results show that pipeline transportation provides the least-cost option, while rail transportation provides the least-CO2 emissions option. In addition, optimal plant capacity was calculated to be about 450 million liters per year (MLY) regardless of the transportation option, so that five becomes the ideal number of biorefineries in Minnesota. Sensitivity analysis on the major assumptions and parameters was performed, and its implications in interpreting the results are discussed.