Alternative fuel is generally means fuel other than petroleum (gasoline) and alcohol-based products that is used for transportation applications. This includes the following:
* methanol * denatured ethanol, and other alcohols * fuel mixtures containing 85 percent or more by volume of methanol, denatured ethanol, and other alcohols with gasoline or other fuels -- natural gas * liquefied petroleum gas (propane) * hydrogen * coal-derived liquid fuels * fuels (other than alcohol) derived from biological materials (biofuels such as soy diesel fuel) * electricity (including electricity from solar energy.)
The term "alternative fuel" does not include alcohol or other blended portions of primarily petroleum-based fuels used as oxygenates or extenders, i.e. MTBE, ETBE, other ethers, and the 10-percent ethanol portion of gasohol.