Transactions of the ASABE Vol. 54(1): 229-238 E 2011 American Society of Agricultural and Biological Engineers ISSN 2151-0032 229 OPTIMAL CORN STOVER LOGISTICS FOR BIOFUEL PRODUCTION: A CASE IN MINNESOTA K. Suh, S. Suh, B. Walseth, J. Bae, R. Barker 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 CO 2 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 CO 2 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 CO 2 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‐CO 2 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. Keywords. CO 2 emission, Corn stover, Cost, Ethanol, Logistics, Transportation. he advantages of using corn stover for bioethanol production have been widely discussed (NREL, 2001; Fargione et al., 2008; Searchinger et al., 2008; Spatari et al., 2005; Perlack et al., 2005; Aden et al., 2002; Sheehan et al., 2003; Perlack and Turhol‐ low, 2003; NASS, 2008; Argonne National Laboratory, 2008; Huang et al., 2009; Eidman et al., 2009; Petrolia, 2008; Til‐ man et al., 2009). According to the 2007 harvested area and yield rate of corn, more than 90 million dry metric tons of corn stover can be produced annually in the U.S. using a 30% collection rate, which translates to 31 billion liters of ethanol (NASS, 2008; Perlack and Turhollow, 2003; Sheehan et al., 2003). Corn stover as an ethanol feedstock is cost‐ competitive (Aden et al., 2002; Petrolia, 2008; Sheehan et al., 2003) and can provide substantial carbon reduction benefits as compared to other feedstocks (Spatari et al., 2005; Liska et al., 2009). Submitted for review in March 2010 as manuscript number FPE 8480; approved for publication by the Food & Process Engineering Institute Division of ASABE in November 2010. The authors are Kyo Suh, ASABE Member Engineer, NorthStar Research Fellow, Institute on the Environment, University of Minnesota, St. Paul, Minnesota; Sangwon Suh, Assistant Professor, Bren School of Environmental Science and Management, University of California, Santa Barbara, California; Brian Walseth, Research Assistant, Junghan Bae, Research Assistant, and Ryan Barker, Research Assistant, Department of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul, Minnesota. Corresponding author: Sangwon Suh, Bren School of Environmental Science and Management, 2400 Bren Hall, University of California, Santa Barbara, CA 93106‐5131; phone: 805‐893‐7185; fax: 805‐893‐7612; e‐mail: suh@bren.ucsb.edu. Despite these benefits, concerns have been raised about using corn stover as a feedstock for ethanol production on the basis of its potential impacts on soil erosion, soil organic car‐ bon, additional fertilizer use, and significant transportation needs (Argonne National Laboratory, 2008; NASS, 2008; Sawyer et al., 2006; Sokhansanj and Turhollow, 2004; Petro‐ lia, 2008; Kumar et al., 2005; Liska et al., 2009). In particular, the low bulk density of corn stover demands substantial increase in transportation needs. The bulk density of corn stover is in the range of 50 to 130 kg m ‐3 , which is much lower than that of corn, which is around 600 kg m ‐3 (Sokhansanj and Turhollow, 2004). Kumar et al. (2005) pointed out that the low bulk density of corn stover requires considerable truck traffic, causing significant air, noise, and light pollution, and proposed pipeline transportation as an al‐ ternative to truck transportation. Mani et al. (2006) studied pelletizing lignocellulosic biomass to increase feedstock bulk density and to reduce transportation needs. Petrolia (2008) estimated the economic feasibility of corn stover as a feedstock for ethanol production and identified densification as a way to reduce transportation costs. However, little is known about the costs and environmen‐ tal impacts of various corn stover transportation options and their possible trade‐offs. The objectives of this article are: (1)Ăto demonstrate a method to estimate the optimal biomass logistics option for biofuel production considering cost and CO 2 emissions, and (2) to apply the method to the case of corn stover in Minnesota, deriving the state's optimal logistics configuration. We examined three transportation options (truck, rail, and pipeline) based on the best available geospa‐ tial data on corn stover production potential. T