Alternative fuels, as defined by the Energy Policy Act of 1992 (EPAct), include ethanol,
natural gas, propane, hydrogen,
biodiesel*, electricity, methanol, and p-series fuels. These fuels are being used worldwide in a variety of vehicle applications.

Using these alternative fuels in vehicles can generally reduce harmful pollutants and exhaust emissions. In addition, most of these fuels can be domestically produced and derived from renewable sources.