Assessment of costs and benefits of flexible and alternative fuel use in the US transportation sector

The DOE is conducting a comprehensive technical analysis of a flexible-fuel transportation system in the United States -- that is, a system that could easily switch between petroleum and another fuel, depending on price and availability. The DOE Alternative Fuels Assessment is aimed directly at questions of energy security and fuel availability, but covers a wide range of issues. This report examines environmental, health, and safety concerns associated with a switch to alternative- and flexible-fuel vehicles. Three potential alternatives to oil-based fuels in the transportation sector are considered: methanol, compressed natural gas (CNG), and electricity. The objective is to describe and discuss qualitatively potential environmental, health, and safety issues that would accompany widespread use of these three fuels. This report presents the results of exhaustive literature reviews; discussions with specialists in the vehicular and fuel-production industries and with Federal, State, and local officials; and recent information from in-use fleet tests. Each chapter deals with the end-use and process emissions of air pollutants, presenting an overview of the potential air pollution contribution of the fuel --relative to that of gasoline and diesel fuel -- in various applications. Carbon monoxide, particulate matter, ozone precursors, and carbon dioxide are emphasized. 67 refs., 6 figs. , 8 tabs