Alcohol fuels for motor vehicles: an overview

Alcohol fuels are expected to be marketed for at least the next decade, initially in gasoline blends and then possibly as neat liquids. Ethanol blends in the form of gasohol are dominant now, but methanol blends have the potential of eventually displacing gasohol in a free market because of their lower cost. Ethanol production for fuel applications is currently capacity-limited and is not expected to displace more than a small percentage of petroleum liquid usage by 1990. Methanol, potentially available in larger quantities than ethanol from such feedstocks as coal, could significantly reduce petroleum liquid usage if a nationwide program were started to expand production. Net-energy production efficiencies of ethanol production plants supplied with corn feedstocks appear to be borderline at best, but research in progress can have a major beneficial effect in delivering more net energy to the marketplace by reducing external energy consumption in integrated biomass production-conversion systems. This paper focuses on the technical aspects of alcohol fuels; but other questions need to be addressed, particularly economic ones. Beef producers are concerned about the effects on meat prices of increased feeding of distillers' grains; some fear that a subsidized alcohol market would sharply raise feed prices. Some feedmore » producers believe that large-scale gasohol marketing will depress soybean meal prices because of the competition from distillers' grains. Highway administrators have indicated concern over the possible effects on highway maintenance and construction programs of reduced tax revenues because of increasing and possibly permanent subsidies for alcohol fuels. These and other factors will have to be considered in the development of large-scale alcohol fuels manufacture.« less