Greenhouse gas emission impacts of alternative-fueled vehicles: Near-term vs. long-term technology options

Alternative-fueled vehicle technologies have been promoted and used for reducing petroleum use, urban air pollution, and greenhouse gas emissions. In this paper, greenhouse gas emission impacts of near-term and long-term light-duty alternative-fueled vehicle technologies are evaluated. Near-term technologies, available now, include vehicles fueled with M85 (85% methanol and 15% gasoline by volume), E85 (85% ethanol that is produced from corn and 15% gasoline by volume), compressed natural gas, and liquefied petroleum gas. Long-term technologies, assumed to be available around the year 2010, include battery-powered electric vehicles, hybrid electric vehicles, vehicles fueled with E85 (ethanol produced from biomass), and fuel-cell vehicles fueled with hydrogen or methanol. The near-term technologies are found to have small to moderate effects on vehicle greenhouse gas emissions. On the other hand, the long-term technologies, especially those using renewable energy (such as biomass and solar energy), have great potential for reducing vehicle greenhouse gas emissions. In order to realize this greenhouse gas emission reduction potential, R and D efforts must continue on the long-term technology options so that they can compete successfully with conventional vehicle technology