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.

Natural Gas Basics

The Basics

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% of the fuel goes to electric power production and the remainder 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 about two-tenths of 1% is used for transportation fuel.

The vast majority of natural gas in the United States is considered a fossil fuel because it is made from sources formed over millions of years by the action of heat and pressure on organic materials. Alternatively, renewable natural gas (RNG), also known as biomethane, is a pipeline-quality vehicle fuel. It is produced by purifying biogas, which is generated through anaerobic digestion of organic materials—such as waste from landfills and livestock—or through thermochemical processes, such as gasification. RNG qualifies as an advanced biofuel under the Renewable Fuel Standard.

Because RNG is chemically identical to fossil-derived conventional natural gas, it can use the existing natural gas distribution system and must be compressed or liquefied for use in vehicles.