An alternative fuel vehicle (AFV) is a vehicle that runs on substances other than the conventional petroleum gas and diesel.
Examples of alternate fuels include electric, solar, biodiesel, ethanol, propane, compressed air, hydrogen, liquid natural gas and liquid petroleum. Researchers have found that even algae could be a potential future alternative fuel source. Many AFVs have flex-fuel engines, which means they can run on more than one type of fuel. The flexibility can provide a second option if one fuel is unavailable and may make it possible to avoid sudden price changes caused by swings in markets. Hybrid vehicles also use a dual-fuel system: a combination of electric batteries and gasoline.
Benefits of using AFVs include reductions in the cost of fuel, carbon emissions and environmental impact. It gives the ability to supply one’s own fuel, even perhaps making fuel from what would otherwise be waste. Alternative fuel vehicles have become increasingly popular over the past couple decades as consumers, car manufacturers and governments have become more concerned with energy conservation and the environmental effects of conventional fuels. Car models like the Toyota Prius have popularized the use of alternative or dual-fuel vehicles.