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Natural Gas Vehicles

About Natural Gas Vehicles

Natural Gas Vehicles (NGVs) are powered by compressed natural gas (CNG) or liquefied natural gas (LNG). Both are cleaner, safer and less expensive than traditional fuels. New developments in engine and vehicle technology, more stringent air quality regulations, and government incentives make this choice increasingly attractive.

There are more than 15 million NGVs worldwide and 135,000 on U.S. roads. In the U.S., most NGVs produced directly at the factory by the vehicle manufacturer are buses, refuse trucks and light- and medium-duty fleet vehicles. However, there are also many models of gasoline-powered vehicles which can be converted to operate on CNG suitable for consumer use.

Our nation has the most extensive natural gas distribution system of any country in the world, making it feasible to install CNG fueling equipment at existing gas stations and other locations supplied from existing natural gas lines. There are more than 1,700 public and private NGV fueling stations available now and the number is growing fast.

Are NGVs right for your lifestyle or business? Contact us for more information. Chattanooga Gas can provide you with clean, affordable natural gas to fuel your vehicles and assist you with evaluating the vehicle and fueling options. 

How NGVs Work

Light-duty natural gas vehicles work much like gasoline-powered vehicles. In a CNG fuel system, high-pressure natural gas moves from the storage tank to the engine where its pressure is reduced to the engine’s required fuel injection system pressure. After the natural gas is injected into the engine, the fuel-air mixture is compressed and ignited by a spark plug. The expanding gases propel the vehicle.

Some heavy-duty vehicles use spark-ignited natural gas systems, but other systems exist as well. High-pressure direct injection engines burn natural gas in a compression-ignition (diesel) cycle. Also, diesel engines can often be converted to burn diesel and natural gas simultaneously in a dual-fuel system.

Benefits of Natural Gas Vehicles

Natural Gas Vehicles can provide many benefits to both you and your environment, including these below:

Proven & Reliable

Nearly 15 million NGVs are in use worldwide, with more than 135,000 in the U.S.

Fuel Savings

The U.S. is the major producer of natural gas. This abundant domestic supply has driven down the price of natural gas, ensuring that the price will remain below that of gasoline and diesel. Compressed Natural Gas (CNG) currently saves up to 50% over conventional fuels, and CNG vehicles are available for all types of applications, including business fleets and vehicles for personal use.

Environmental Benefits

CNG vehicles produce up to 90% fewer emissions than gasoline or diesel and reduce greenhouse gases 15-20% over diesel and gasoline. If the CNG is sourced from Renewable Natural Gas (RNG) suppliers like landfills, water treatment plants, or agricultural waste digestors, the reduction in greenhouse gases is even more significant; in the 80-90% range or even carbon negative in some cases.

Reduced Maintenance Costs

Oil change intervals for NGVs may often be extended since natural gas burns cleaner than gasoline or diesel. Also, because natural gas engines have practically no carbon build-up, it is not uncommon for them to last longer than gasoline and diesel engines. Today's diesel vehicles require maintenance intensive exhaust treatment equipment such as Diesel Particulate Filters (DPF), Selective Catalytic Reduction (SCR), and Diesel Exhaust Fluid (DEF) to meet emission requirements. In contrast, heavy duty natural gas engines require only a maintenance-free exhaust catalyst so all that expensive equipment is eliminated.


Heavy-duty NGVs have an 80-90% lower noise level than comparable diesel vehicles.


Significant federal and/or state tax credits and other incentives are often available for converting to NGVs.


Natural gas in an inherently safe fuel and, unlike gasoline, it dissipates into the atmosphere in the event of an accidental release. The high ignition temperature and limited flammability range make accidental ignition or combustion of natural gas unlikely.

CNG vehicle storage cylinders and other fuel system components are manufactured to strict standards and installed in accordance with applicable codes.  The industry has an excellent safety record, especially when compared to other fuel types.

For more information on NGV safety, codes and standards applicable to NGVs and fueling equipment, and more, please visit NGVAmerica, which coordinates and implements a variety of public awareness, education, market research, codes and standards and technology programs for natural gas vehicles.