TECHNOLOGY
NG enters the vehicle through the natural gas fill valve and flows into high-pressure cylinders. When the engine requires natural gas, the gas leaves the cylinders and passes through the master manual shut-off valve. The gas travels through the high-pressure fuel line and enters the engine compartment. Gas enters the regulator, which reduces the gas pressure used for storage (up to 3,600 psi) to the required vehicle fuel injection system pressure. The natural gas solenoid valve allows natural gas to pass from the regulator into the gas mixer or fuel injectors. The solenoid valve shuts off the natural gas when the engine is not running. Natural gas mixed with air flows down through the carburetor or fuel-injection system and enters the engine combustion chambers where it is burned to produce power, just like gasoline.1

FUEL TYPES

• Compressed natural gas (CNG) is stored in tanks at high pressure and gets about the same fuel economy as a traditional gasoline vehicle. Most commonly used with cars and light-duty trucks.

• Liquefied natural gas (LNG) is purified, condensed and liquefied natural gas. Provides more energy in a smaller volume compared to CNG. Typically only used with heavy-duty vehicles.

ENGINE TYPES

• Dual-fuel or bi-fuel natural gas vehicles have 2 separate fueling systems enabling the vehicle to use either natural gas or traditional fuels like gasoline and diesel.

• Dedicated natural gas vehicles are designed to only run on natural gas.

ENVIRONMENTAL IMPACT
NGVs emit 60-90% less smog-producing pollutants and 30-40% less GHGs than traditional gasoline powered vehicles.

BENEFITS
Natural gas is a domestically produced fuel with existing delivery infrastructure. NG prices are more stable than gasoline and often less expensive. Owners will benefit from lower maintenance costs due to thecleaner burning fuel.2

DISADVANTAGES
Natural gas is a non-renewable fossil fuel. NGVs experience fewer miles on a tank of fuel than gasoline powered vehicles. NGVs often involve a higher initial investment that gasoline powered vehicles; however cost is expected to decrease over time, like many other emerging technologies, with increased adoption. NGV fuel cylinders are bulky and take up a lot of room. The current market has a limited availability of vehicles.

VALLEY ACCESS POTENTIAL
There are natural gas fueling stations throughout the state, and over 1,000 nationwide.3 Over 40 different car manufacturers offer NG models including Honda, Toyota, Ford, Chrysler, Chevy, and Mercedes. NGVs can be found at dealerships around the Valley.

For more information on NGVs visit the U.S. Dept. of Energy at
www.afdc.energy.gov/afdc/vehicles/natural_gas.html

1 DOE EERE http://www.afdc.energy.gov/afdc/vehicles/natural_gas_what_is.html (last accessed April 23, 2009)
2 US EPA http://www.fueleconomy.gov/FEG/bifueltech.shtml (last accessed April 23, 2009)
3 NG Prices www.cngprices.com (last accessed April 23, 2009)