Alternative Fuels

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| Natural Gas Vehicles | Fuel Availability | Safety Characteristics |  Additional Resources |

Natural gas is a fossil fuel extracted from gas wells or in conjunction with crude oil production. It can also be produced as a by-product of landfill operations, dairy farms, wasterwater treatment plants, etc. Natural gas is composed primarily of methane, along with other hydrocarbons such as ethane, propane and butane. It can be stored on a vehicle in gaseous form, compressed natural gas (CNG), or as a liquid, liquid natural gas (LNG). Natural gas can also be blended with hydrogen to create a hydrogen/natural gas (HCNG) blend. Certain blends of HCNG are called hythane.

Natural gas can be used in the full range of vehicles, from passenger vehicles to heavy-duty trucks. CNG light-, medium-, and heavy-duty vehicles are available from automobile manufactures. Vehicles can be dedicated, operating only on natural gas, or bi-fuel, capable of switching between natural gas and gasoline/diesel.  LNG vehicles are also available, though they are focused on heavy-duty vehicles.

Natural gas vehicles are suitable for a wide range of applications. Local users of natural gas vehicles include: City of Seattle, Puget Sound Energy, Port of Seattle, Saybr Contractors, Shuttle Express, STITA taxis, Fort Lewis and Pierce Transit. The gaseous nature and energy content of CNG require there to be greater storage capacity to achieve a comparable range to gasoline and diesel vehicles. As a result, some natural gas vehicles have a more limited range or have reduced passenger or storage capacity due to space requirements for CNG fuel tanks. LNG does not present the same range limitations, as its physical characteristics allow two to four times more LNG than CNG to be stored in the same amount of space.

Refueling CNG vehicles can be done using fast-fill stations or using slow-fill systems installed at residences or businesses. The local natural gas fuel station network consists of two public CNG refueling stations and several privates stations, which will allow access by special arrangement. There are currently no publicly accessible LNG stations in the Puget Sound area.

Pierce Transit has been operating its "Clean Machine" natural gas buses since 1986, becoming one of the first public transit fleets to use alternative fuel buses.  The natural gas program has not expanded to a 100% percent natural gas fleet.

Environmental & health benefits: Natural gas has lower carbon monoxide, particulate matter, nitrogen oxide, and carbon dioxide emissions compared to gasoline and diesel vehicles. In some cases, natural gas engines have demonstrated over 90% reductions of carbon monoxide (CO) and particulate matter and more than 50% reduction in nitrogen oxides (NO_x). In addition, natural gas vehicles produce significantly lower evaporative emissions during fueling and operating. Natural gas also contains relatively few toxic contaminants.

Economics: The cost of natural gas vehicles from automobile manufacturers is typical 25% higher than gasoline models. Converting a gasoline passenger vehicle or light-duty truck to operate on natural gas costs approximately $5,000. These costs may be offset by lower operating and maintenance costs. In general, natural gas fuel is less expensive than gasoline and diesel. In addition, because natural gas burns cleaner, there is a reduction in vehicle maintenance required, as the interval between oil changes can be increased and there is increased spark plug life. Overall engine life is also extended due to fewer engine deposits. In addition, Washington State offers a state fuel tax incentive for CNG vehicles.

Safety characteristics: Natural gas has been used as a motor fuel for more than 60 years with an excellent safety record. Natural gas has a higher ignition temperature than gasoline and diesel fuels, posing a reduced risk of accidental ignition or combustion. In addition, because natural gas is lighter than air, it will rise and dissipate rapidly in the unlikely event of a leak, as opposed to other fuels which tend to pool on the ground or enter sewer or water systems.  Some safety issues are associated with LNG. Because the gas is cooled to –260 degrees, frost bite can result from exposure liquid fuel, cold metals or cold gas. Also, because odorants cannot be added to LNG to allow for its easy detection, special methane gas detectors should be installed.

Additional Resources:

• The U.S. Department of Energy provides additional information on natural gas and natural gas vehicles.
• Natural Gas Vehicle Coalition The NGVC is a national organization dedicated to the development of a growing, sustainable and profitable natural gas vehicle market.  The website provides information on available natural gas vehicles, the benefits of NGVs, and updates on government policies and legislation.
• Prometheus Energy Company Prometheus Energy Company is an alternative fuel company specializing in the production, sale and distribution of LNG, produced from otherwise wasted or stranded domestic resources and used primarily as an alternative transportation fuel. LNG is clean-burning, economical and safe. Prometheus currently occupies a 23,000 square foot engineering, advanced development and operations facility in Seattle. Our current projects, the first of which will come online by the first quarter of 2006, will produce in excess of 50,000 gallons of LNG per day to be sold into the domestic vehicle fuels market by the end of 2006.
• Puget Sound Energy Puget Sound Energy (PSE) has been using natural gas vehicles since 1979 and now has a fleet of more than 150 passenger vehicles, trucks and vans. PSE also owns, operates and maintains several CNG fueling stations throughout the Puget Sound region. PSE is available for consultation on the implementation of CNG vehicle programs and the development of CNG fuel stations, and also provides a significant role in the actual construction of CNG fuel stations. Contact Chuck Dougherty at 253.476.6202.
• Clean Energy Fuels Corporation Since the early 1980s, the Clean Energy  team, formerly known as ENRG Fuels, has been building and servicing natural gas refueling stations.  The website provides information about their services, the benefits of natural gas vehicles, available natural gas vehicles and a fuel savings calculator.
• Saybr Contractors, Inc. of Puyallup, Washington is a general contractor specializing in removal and replacement of underground and aboveground fuel systems, underground utilities, remediation, demolition, and complete site development. Services include the development of natural gas fuel facilities.
• Fuel Maker Corporation  FuelMaker has a full line of Vehicle Refueling Appliances (VRA) to provide a convenient and inexpensive means to refuel vehicles on site. Fast- and slow-fill systems are available for installation at residences or businesses.  Models ranging in price from $6,000 to $20,000, plus installation. FuelMaker sometimes provides special promotions in conjunction with Honda to reduce the cost of the fueling equipment.