(737e) Locating Nth-Plants for Blended Feestock Conversion and Preprocessing Nationwide: Biorefineries and Depots

Department of Energy laboratories have proposed that the nth-plant indicates a scenario with a mature conversion technology that takes advantage of economies of scale. Defining the nth-plant scenario is imperative to ultimately transform the nation’s renewable biomass resources into cost-competitive, high-performance feedstocks for production of biofuels and bioproducts. To determine the nth-plant scenario for blended feedstock (switchgrass and corn stover harvested by either a 2-pass or a 3-pass method), we used a two-step process with a modified version of INL’s (Idaho National Laboratory) Least-Cost Formulation model, a Mixed Integer Linear Programming (MILP) Model to deliver on-spec biomass of multiple crops that considers biomass quantity and quality at a total delivered feedstock cost that is less than $79.07/ dry ton (2016$).. First, plants were located to represent either biorefineries in the conventional supply chain system or preprocessing depots in the advanced supply chain system. In this first part of the analysis, 247 depots were supplied with 70.7 million dry tons of corn stover from 416 sources and 32 million dry tons of switchgrass from 751 sources. The second part of the MILP model will determine the location of biorefineries and depots in the conventional and advanced logistic system. Additional inputs to the model were the resource quantities presented in the BT16 by Oak Ridge National Laboratory, the design case by the National Renewable Energy Laboratory for biochemical conversion, and the targeted delivery feedstock cost to the reactor throat as defined by Idaho National Laboratory. The results from this study will be compared with outputs from the Supply Characterization Model (SCM) from Oak Ridge National Laboratory.