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Welcome To Washington Gas

For more than 165 years Washington Gas has been distributing natural gas to customers in the District of Columbia, Maryland and Virginia. We bring natural gas to your home or business safely and reliably.

Natural Gas Vehicles

The Clean Way to Go with a Domestic Fuel

As the nation looks for ways to reduce air pollution from vehicles, natural gas is the ideal environmental alternative to gasoline. For starters, natural gas is clean. (It's the same clean-burning natural gas that you use to cook or heat your home.) Vehicles fueled with natural gas can dramatically reduce emissions of carbon monoxide and reactive hydrocarbons-which interact with sunlight to produce ozone, the principal component of smog. Natural Gas Vehicles also reduce emissions of carbon dioxide, the principal "greenhouse" gas.

Another plus-natural gas is a domestic fuel. Nearly 93 percent of the natural gas used in this country is produced in the United States. Almost all the rest comes from Canada.

And natural gas has a proven safety record. Because natural gas is lighter than air, any leaking fuel will not pool like liquids, but will dissipate into the air.

Frequently Asked Questions

What is a natural gas vehicle?

A natural gas vehicle is one that runs on natural gas instead of gasoline or diesel fuel.

Is using natural gas in engines a new idea?

Not at all. The first natural gas engine was built in 1860, before the development of the gasoline engine. Natural gas vehicles have been used with much success in the United States since the 1960s and in Europe for nearly 50 years. In fact, there are currently more than 30,000 natural gas vehicles on U.S. roads and over 700,000 worldwide.

How do vehicles run on natural gas?

Natural gas used by these vehicles is compressed to about 3,500 pounds per square inch and is stored in cylinders mounted on the vehicle. When natural gas is required by the engine, it is released from the cylinders and passes into a pressure regulator that brings it almost to atmospheric pressure. Then it goes into an air-mixer, where it is combined with air in the precise air-to-gas ratio required for ignition. Lastly, the natural gas flows into the engine's intake air stream for combustion. 

Natural Gas Vehicle Image
  • Fill point -- uses hose to refuel cylinder in minutes.

  • Regulator - reduces fuel pressure.

  • Tubing - transports gas from cylinders to the engine.

  • Cylinders - stores natural gas while actually adding to vehicle's structural strength.

How do you fuel a natural gas vehicle, and how long does it take?

A natural gas vehicle is fueled using a hose and nozzle that are attached to a natural gas pump. A natural gas vehicle can be fueled at a "fast-fill" pump in about the same time it takes to fuel any gasoline- or diesel-powered vehicle. Or it can be fueled in five-to-eight hours using a "slow-fill" method. This method is often used for fleet vehicles that can return to a central station at the end of the day and be refueled during the night.

What is the driving range of a natural gas vehicle?

That depends on the size and number of natural gas storage cylinders and on driving conditions. In a passenger car, two cylinders of natural gas can provide the equivalent of about eight-and-one-half gallons of gasoline. Trucks and other larger vehicles can be equipped with more cylinders as required.

What kinds of vehicles can be converted to use natural gas?

Cars, trucks, vans and buses can be converted to run on natural gas. Fleet operators, such as delivery services, taxi companies and school districts, now are operating vehicles on natural gas. In fact, WMATA - Metrobus, Montgomery County - Ride-On, and Arlington County - ART buses are converting a significant portion of their fleet to operate on natural gas. .

Can a vehicle that has been converted to run on natural gas continue to operate on gasoline?

Yes. Vehicles converted to run on natural gas may retain the ability to operate on gasoline. The driver can switch from one fuel to another safely while driving. These vehicles are known as bi-fuel vehicles. Vehicles that run solely on natural gas are known as "dedicated" natural gas vehicles.

Is any special training needed to use natural gas vehicles?

No. A natural gas vehicle operates like any gasoline- or diesel-powered vehicle. In the case of bi-fuel vehicles, some simple instruction may be needed to use the fuel selector.

What are the advantages of using natural gas as a vehicular fuel?

Natural gas is the cleanest-burning fossil fuel available. Natural gas vehicles can achieve up to a 93 percent reduction in carbon monoxide emissions, 33 percent reduction in nitrogen oxides emissions, and a 50 percent reduction in reactive hydrocarbons in comparison with gasoline vehicles. Natural gas vehicles emit virtually no carcinogenic particulate matter. In addition, because natural gas burns cleanly, maintenance costs are low. Natural gas extends the time needed between tune-ups and oil changes, and results in less engine wear-and-tear. Also, natural gas has an octane rating of 130, which means it has an efficiency advantage over gasoline.

Emissions Rate Summary









.35 .04 1.4 .66

Methanol (M85)

.25 .09 1.0 .45

Ethanol (E85)

1.02 .05 1.8 .61


.20 0 1.4 .27

Natural Gas

.19 0 0.1 .44


Is using natural gas in a vehicle safe?

Yes. First, the natural gas storage cylinders are very sturdy, a half-inch thick compared to an eighth or sixteenth of an inch for gasoline tanks. Second, natural gas is lighter than air, so even if a leak develops, the gas dissipates into the air instead of forming a spreading pool or vapor cloud on the ground, as other fuels do. Third, the combustion temperature of natural gas, 1200 degrees Fahrenheit, is higher than that of gasoline, 600 degrees Fahrenheit. An American Gas Association study reported no injuries or fatalities after more than a half billion miles driven with natural gas vehicles.