ALTERNATIVE FUELS

The definition of alternative fuel varies according to the context of its usage. In the context of  petroleum substitutes, the term 'alternative fuel' can imply any available fuel or energy source, and does not necessarily refer to a source of renewable energy. In the context of environmental sustainability, 'alternative fuel' often implies an ecologically benign renewable fuel.
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Substitutes for traditional liquid, oil-derived motor vehicle fuels like gasoline and diesel. Includes mixtures of alcohol-based fuels with gasoline, methanol, ethanol, compressed natural gas, and others.

Substitutes for traditional liquid, oil-derived motor vehicle fuels like gasoline and diesel. Includes methanol, ethanol, biodiesel, compressed natural gas, and others. The alternatives are promoted for pollution reduction properties and/or to reduce U.S. dependence on imported oil. Ethanol can be produced from grain, agricultural wastes, and excess crops.