Activitate

Propane Fuel Basics

Also known as liquefied petroleum gas (LPG) or propane autogas, propane is a clean-burning alternative fuel that's been used for decades to power light-, medium-, and heavy-duty propane vehicles.

Propane is a three-carbon alkane gas (C3H8). It is stored under pressure inside a tank as a colorless, odorless liquid. As pressure is released, the liquid propane vaporizes and turns into gas that is used in combustion. An odorant, ethyl mercaptan, is added for leak detection. (See fuel properties.)

Propane has a high octane rating, making it an excellent choice for spark-ignited internal combustion engines. If spilled or released from a vehicle, it presents no threat to soil, surface water, or groundwater. Propane is produced as a by-product of natural gas processing and crude oil refining. It accounts for about 2% of the energy used in the United States. Of that, less than 3% is used for transportation. Its main uses include home and water heating, cooking and refrigerating food, clothes drying, and powering farm and industrial equipment. The chemical industry also uses propane as a raw material for making plastics and other compounds.

Propane as an Alternative Fuel

Interest in propane as an alternative transportation fuel stems from its domestic availability, high-energy density, clean-burning qualities, and relatively low cost. It is the world's third most common transportation fuel, behind gasoline and diesel, and is considered an alternative fuel under the Energy Policy Act of 1992.

Propane used in vehicles is specified as HD-5 propane and is a mixture of propane with smaller amounts of other gases. According to the Gas Processors Association's HD-5 specification for propane, it must consist of at least 90% propane, no more than 5% propylene, and 5% other gases, primarily butane and butylene. (See fuel properties.)