Compressed Natural Gas (CNG)
Driving a compressed natural gas (CNG) vehicle reduces smog-forming and greenhouse gas emissions as well as our dependence on foreign oil. Although the range between fills is slightly less than their gasoline counterparts, the benefits such as HOV lane access, cheaper fuel and the ability to fuel at home can outweigh this seemingly negative attribute.
How It Works
Natural gas is a mixture of hydrocarbons consisting mainly of methane. Most of the natural gas consumed in the United States is domestically produced – reducing the nation's dependence on foreign oil. The natural gas used in passenger vehicles is typically in compressed form and stored in a very safe high pressure tank in the vehicle’s trunk. Today’s natural gas vehicles are called "dedicated" systems designed to run only on natural gas. In the past, some bi-fuel natural gas vehicles were designed to have two separate fueling systems that allow the vehicle to use either natural gas or gasoline.
Currently, there is only one manufacturer making a natural gas passenger car that is available to consumers as well as fleets, the Honda Civic GX. It also happens to be the cleanest combustion vehicle on the road today. In the past, other makes and models were available and several were used in taxi fleets. There are many CNG conversion companies that convert certain models to CNG, and these are represented in the CNG vehicle search. However, these conversion models are currently only larger, fleet application vehicles such as vans and trucks. More CNG light-duty passenger car models are expected soon.
The initial incremental cost of a CNG vehicle is typically higher than its gasoline counterpart, however, natural gas costs on average one-third less than conventional gasoline and there are often incentives to offset the higher price.
There are over 150 CNG refueling sites in California and more than 1,000 CNG refueling stations nationwide. In addition, consumers can purchase a "slow fill" system called Phill by Fuelmaker that can be installed in a home garage for overnight refueling. Resources for finding CNG refueling locations are:
- California Natural Gas Vehicle Coalition Station Finder
- Clean Car Maps: Searchable database of EV chargers and alternative fueling stations in California, including compressed natural gas, liquefied natural gas, liquefied petroleum, ethanol (E85), hydrogen and biodiesel.
- Department of Energy's Alternative Fuels Data Center: A site developed by the Department of Energy that provides maps to refueling stations in the US for CNG, LPG/propane, ethanol, electric, biodiesel, hydrogen, and liquefied natural gas (LNG).
- Mapquest Station Finder
- PHILL by BRC FuelMaker: Phill can be easily installed at home and consumption directly charged to your gas bill costs.
Compressed natural gas cars have similar performance to their gasoline counterparts, however they typically have a lower range between fills.
Typical CNG vehicles can reduce smog-forming emissions of Carbon Monoxide (CO) by 70 percent, Non-Methane Organic Gas (NMOG) by 87 percent and Oxides of Nitrogen (NOx) by 87 percent. Also, CNG vehicles typically have 20 percent fewer greenhouse gas emissions than gasoline powered cars. In addition, natural gas is not toxic or corrosive and will not contaminate ground water.
To compare the environmental benefits between cars you are shopping for, remember to look for high ratings on the Fuel Economy and Environment Label.
CNG, unlike gasoline, dissipates into the atmosphere in the event of an accident. Gasoline pools on the ground creating a fire hazard. The fuel storage cylinders used in CNG vehicles are much stronger than gasoline fuel tanks. The design of CNG cylinders are subjected to a number of federally required "severe abuse" tests, such as heat and pressure extremes, gunfire, collisions and fires.
Finally, CNG fuel systems are "sealed," which prevents any spills or evaporative losses. Even if a leak were to occur in an natural gas vehicle fuel system, the natural gas would dissipate up into the air because it is lighter than air.
- California Air Resources Board’s Alternative Fuels Program
- The California Natural Gas Vehicle Coalition
- The Natural Gas Vehicle Coalition