Alternative Fuels and Advanced Vehicles

Biodiesel is a domestically produced, renewable fuel that can be manufactured from vegetable oils, animal fats, or recycled restaurant grease for use in diesel vehicles or any equipment that operates on diesel fuel. Biodiesel's physical properties are similar to those of petroleum diesel.

Electricity can be used to power electric vehicles (EVs), including both all-electric vehicles, also called battery-electric vehicles (BEVs), and plug-in hybrid electric vehicles (PHEVs). These vehicles can charge their batteries by drawing electricity directly from the grid and other off-board electrical power sources. In contrast, hybrid electric vehicles (HEVs) are fueled with liquid fuels, like gasoline, but use small batteries to recapture energy otherwise lost during braking (ultimately boosting fuel economy). PHEVs can use off-board electricity for power, which classifies them as an EV, but can also use liquid fuels and operate similar to a HEV if necessary. Using electricity to power vehicles can have significant energy security and emissions benefits.

Ethanol is a renewable fuel made from corn and other plant materials. Ethanol use is widespread, and more than 98% of gasoline in the U.S. contains some ethanol. The most common blend of ethanol is E10 (10% ethanol, 90% gasoline). Ethanol is also available as E85 (or flex fuel)—a high-level ethanol blend containing 51% to 83% ethanol, depending on geography and season—for use in flexible fuel vehicles. E15, another blend, is increasing its market presence. It is approved for use in model year 2001 and newer light-duty conventional gas vehicles.

Hydrogen, when used in a fuel cell to provide electricity, is a zero tailpipe emissions alternative fuel produced from diverse energy sources. Currently, drivers of light-duty fuel cell electric vehicles (FCEVs) can fuel up at retail stations in less than 5 minutes and obtain a driving range of more than 300 miles. Research and commercial efforts are under way to expand the limited hydrogen fueling infrastructure and increase the production of FCEVs.

Natural gas, a domestically produced gaseous fuel, is readily available through the existing natural gas distribution system. Whether produced via conventional or renewable methods, this clean-burning alternative fuel must be compressed or liquefied for use in vehicles.

Propane, also known as liquefied petroleum gas (LPG) or propane autogas, has been used worldwide as a vehicle fuel for decades. It is stored as a liquid, and propane fueling infrastructure is widespread.