Life Cycle Greenhouse Gas Emissions and Costs of Production of Diesel and Jet Fuel from Municipal Solid Waste.

This paper quantifies and compares the life cycle GHG emissions and costs of production of diesel and jet fuel derived from municipal solid waste (MSW) in the United States via three thermochemical conversion pathways: conventional gasification and Fischer-Tropsch (FT middle distillate, MD), plasma gasification and Fischer-Tropsch (Plasma FT MD), and conventional gasification, catalytic alcohol synthesis, and alcohol-to-jet upgrading (ATJ MD). We use expanded system boundaries to capture the change in existing MSW use and disposal, and account for parameter uncertainty with Monte Carlo simulations. We estimate median life cycle GHG emissions of 32.9, 62.3, and 52.7 gCO2e/MJ for FT, Plasma FT and ATJ MD fuels, respectively, compared to a baseline of 90 gCO2e/MJ for conventional MD fuels. Median minimum selling prices are estimated at 0.99, 1.78, and 1.20 $ per liter with the probability of achieving a positive net present value of fuel production at market prices of 14%, 0.1% and 7% for FT, Plasma FT and ATJ MD fuels, respectively. If the societal perspective rather than an investor's perspective is evaluated, then the probability of positive net present value of fuel production increases to 93%, 67%, and 92.5% for the FT, Plasma FT, and ATJ MD fuels, respectively.

Water consumption footprint and land requirements of large-scale alternative diesel and jet fuel production.

Middle distillate (MD) transportation fuels, including diesel and jet fuel, make up almost 30% of liquid fuel consumption in the United States. Alternative drop-in MD and biodiesel could potentially reduce dependence on crude oil and the greenhouse gas intensity of transportation. However, the water and land resource requirements of these novel fuel production technologies must be better understood. This analysis quantifies the lifecycle green and blue water consumption footprints of producing: MD from conventional crude oil; Fischer-Tropsch MD from natural gas and coal; fermentation and advanced fermentation MD from biomass; and hydroprocessed esters and fatty acids MD and biodiesel from oilseed crops, throughout the contiguous United States. We find that FT MD and alternative MD derived from rainfed biomass have lifecycle blue water consumption footprints of 1.6 to 20.1 Lwater/LMD, comparable to conventional MD, which ranges between 4.1 and 7.4 Lwater/LMD. Alternative MD derived from irrigated biomass has a lifecycle blue water consumption footprint potentially several orders of magnitude larger, between 2.7 and 22 600 Lwater/LMD. Alternative MD derived from biomass has a lifecycle green water consumption footprint between 1.1 and 19 200 Lwater/LMD. Results are disaggregated to characterize the relationship between geo-spatial location and lifecycle water consumption footprint. We also quantify the trade-offs between blue water consumption footprint and areal MD productivity, which ranges from 490 to 4200 LMD/ha, under assumptions of rainfed and irrigated biomass cultivation. Finally, we show that if biomass cultivation for alternative MD is irrigated, the ratio of the increase in areal MD productivity to the increase in blue water consumption footprint is a function of geo-spatial location and feedstock-to-fuel production pathway.