Economic and Environmental Sustainability of Vegetative Oil Extraction Strategies at Integrated Oilcane and Oil-Sorghum Biorefineries

The production of biodiesel from conventional oilseed crops (e.g., soybean) is limited by the low productivity of oil per hectare. Oilcane (derived from sugarcane) holds the potential to improve vegetable oil production in agriculture to help meet projected demand for oil-based biofuels. However, the financial viability of oilcane-derived biofuels remains uncertain, with key questions centered on the technical feasibility of vegetative oil recovery and the economic/environmental implications of designing integrated biorefineries to process multiple oil-rich feedstocks. To address these questions, two biorefinery configurations producing biodiesel and ethanol were evaluated: (i) direct cogeneration of heat and power from bagasse (lower oil recovery) and (ii) an integrated, single-step co-fermentation of both extruded juice and bagasse hydrolysate (higher oil recovery). Sensitivity and uncertainty analyses demonstrated the sustainability gains of improved oil recovery, higher feedstock oil content, and the integration of oil-sorghum processing when oilcane is not in season. For the direct cogeneration and co-fermentation configurations, Monte Carlo simulations resulted in maximum feedstock purchase prices of 34.7 [22.4, 48.4] (median; 5th and 95th percentiles in brackets) and 40.0 [19.3, 63.7] USD·MT-1 and life cycle global warming potentials of 0.313 [0.285, 0.345] and 0.320 [0.294, 0.351] kg CO2-eq·L-1 of ethanol (under economic allocation), respectively.