Types of Alternative Fuels
Natural Gas
Natural gas is an odorless, gaseous mixture of hydrocarbons—predominantly made up of methane (CH4). It accounts for about 30% of the energy used in the United States. About 40% goes to electric power production and the remaining is split between residential and commercial uses, such as heating and cooking, and industrial uses. Although natural gas is a proven, reliable alternative fuel that has long been used to power natural gas vehicles, only a small percentage is used for transportation fuel. To learn more visit, https://afdc.energy.gov/fuels/natural_gas_basics.html.
Renewable Natural Gas (RNG)
Renewable natural gas (RNG) is a pipeline-quality gas that is fully interchangeable with conventional natural gas and thus can be used in natural gas vehicles. RNG is essentially biogas (the gaseous product of the decomposition of organic matter) that has been processed to purity standards. Like conventional natural gas, RNG can be used as a transportation fuel in the form of compressed natural gas (CNG) or liquefied natural gas (LNG). Biogas can be sourced from landfills, livestock operations, and waste water treatment plants.
Propane
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. Propane fuel has a lower carbon content than conventional gasoline and diesel fuel. When used as a vehicle fuel, propane can offer life cycle greenhouse gas (GHG) emissions benefits over conventional fuels, depending on vehicle type, age, and drive cycle. To learn more visit, https://afdc.energy.gov/fuels/propane.html.
Electric
Electricity can be used to power plug-in electric vehicles (PEVs), including all-electric vehicles and plug-in hybrid electric vehicles. These vehicles can draw electricity directly from the grid and other off-board electrical power sources and store it in batteries. In contrast, hybrid electric vehicles are fueled with liquid fuels, like gasoline, but use batteries to recapture energy otherwise lost during braking (ultimately boosting fuel economy). Using electricity to power vehicles can have significant energy security and emissions benefits. To learn more visit, https://afdc.energy.gov/fuels/electricity.html.
Ethanol
Ethanol is a renewable fuel made from corn and other plant materials. The use of ethanol 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 is defined by the Environmental Protection Agency as a blend of 10.5% to 15% ethanol with gasoline. E15 is an approved ethanol blend for use in model year 2001 and newer light-duty conventional gas vehicles. To learn more visit, https://afdc.energy.gov/fuels/ethanol.html.
Biodiesel
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. To learn more visit, https://afdc.energy.gov/fuels/biodiesel.html.
Hydrogen
Hydrogen, when used in a fuel cell to provide electricity, is an emissions-free alternative fuel produced from diverse energy sources. Currently, drivers of 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. To learn more visit, https://afdc.energy.gov/fuels/hydrogen.html.
