About alternative fuel source

(from Wikipedia) The definition of alternative fuel varies according to the context of its usage. In the context of petroleum substitutes, the term 'alternative fuel' can simply 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. Often, they produce less pollution than gasoline or diesel. Alternative fuels, also known as non-conventional fuels, are any materials or substances that can be used as a fuel, other than conventional fuels. Conventional fuels include: fossil fuels (petroleum (oil), coal, propane, and natural gas), and also in some instances nuclear materials such as uranium. Some well known alternative fuels include biodiesel, bioalcohol (ethanol, butanol), chemically stored electricity (batteries and fuel cells), hydrogen, non-fossil methane, non-fossil natural gas, vegetable oil and other biomass sources.