Biomass and natural gas as co-feedstocks for production of fuel for fuel-cell vehicles

Prospects are examined for utilizing renewable energy crops as a source of liquid fuel to mitigate greenhouse gas emissions from mobile sources and reduce dependence on imported petroleum. Fuel-cell vehicles would provide a promising technology for coping with the environmental and economic effects of an expanding vehicle fleer and a decreasing petroleum supply. Fueled with methanol or hydrogen derived From biomass, fuel cells can also effectively address the problem of CO2 emissions From that fleet. The extent to which this combination might affect petroleum displacement depends on the amount of biomass that could be produced and the efficiency of its conversion to a fuel compatible with fuel cells. Reduction of net CO2 emissions by the best current bio-fuel technology will be limited by biomass supply. Biomass conversion efficiency, petroleum displacement and overall net CO2 emission reduction can be improved, and the cost of fuel minimized, by use of natural gas as a co-feedstock. The extra hydrogen provided by natural gas allows these improvements by eliminating the partial shift of CO to CO2 that is otherwise necessary; elimination of that step and additional in situ leveraging of fuel yield by conventional reforming reactions also reduce the production cost. A thermochemical process utilizing both biomass and natural gas as co-feedstocks is compared with other options for methanol production and CO2 mitigation using either biomass or natural gas alone. Use of natural gas as co-feedstock makes possible the additional environmental advantage of utilizing waste methane from landfills and waste-water treatment facilities, as well as the carbonaceous solid wastes and sludge from those facilities, for conversion to clean transportation fuel. Greenhouse pas emissions From these important municipal sources can thus be concurrently I educed, together with landfill disposal requirements. Published by Elsevier Science Ltd.