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Natural Gas Vehicles, Today's Transportation Alternative   Date: May-04-2000 Natural Gas Vehicles: Today's Transportation Alternative Whether in compressed or liquid form, natural gas is widely seen as a "bridge" fuel to take the transportation sector from gasoline and diesel to electric, hybrid-electric and fuel-cell vehicles sometime in the 21st century. Until those technologies are ready for widespread commercialization, however, natural gas is likely to be the advanced fuel of choice for many fleet users because it offers a combination of vehicle variety, fuel access, cost advantages and emissions benefits that other alternatives are hard-pressed to match. Abundant in supply and cleaner burning than all other fossil fuels, domestically produced and distributed widely through a well-developed pipeline infrastructure, natural gas has proven in many ways to be a worthy successor to gasoline and diesel. Yet the fuel itself as well as natural gas vehicle and equipment technology suffer from several practical limitations that hamper their acceptance by vehicle owners. Storage is one such limitation. Compressed natural gas (CNG) is compressed to as much as 3,600psi for greater storage volume, which requires costly compressor, onsite and onboard storage equipment. Liquefied natural gas (LNG) is stored cryogenically to -260°F, which presents special handling and fuel storage challenges as well. Storage, both on the vehicle and off, represents a major component of the extra cost associated with building a natural gas fueling station and acquiring a natural gas vehicle. However, users often can offset at least a portion of that extra cost by capitalizing on the lower pump price of natural gas - typically 10 percent to 30 percent below that of gasoline. Driving range is another drawback commonly associated with NGVs. As a liquid, LNG offers more efficient use of onboard storage space than does CNG and thus is considered most viable for heavy-duty applications. Still, whether powered by LNG or CNG, most natural gas vehicles cannot measure up to gasoline or diesel models in the area of driving range. That may change, however, when new integrated storage technology comes to market in the next several years. There is little argument about the ability of natural gas to reduce vehicle emissions. When used in a vehicle, the fuel emits significantly less of the harmful pollutants that are increasingly targeted for reduction by government regulations. NGVs come in a variety of types, including dedicated models that run only on natural gas, bifuel models that run on either natural gas or gasoline and dual-fuel models, which may run on natural gas and diesel fuel at the same time. Between 40 and 50 automotive companies around the world - most of the major manufacturers - now offer natural gas-powered models, more than any other advanced fuel. So vehicle variety is less of an issue than in years past. Fuel-dedicated, factory-built natural gas vehicles are widely accepted as the most clean-burning, fuel-efficient and technologically advanced NGVs, compared to bifuel vehicles that are capable of running on natural gas or another fuel, and compared to vehicles converted to use natural gas with aftermarket equipment. However, practical considerations such as fuel access, driving range, cost and model variety still make vehicle conversions a viable alternative for many users. Today's natural gas vehicles perform about equal to their diesel and gasoline counterparts in most major areas, even surpassing traditional fuels in such areas as maintenance, engine life and of course, emissions. Though fuel stored at high pressure or in cryogenic form requires unique equipment, training and handling, natural gas vehicles enjoy a sparkling safety record that measures up to any fuel. All NGV equipment in North America - and most used worldwide - is certified to rigorous safety standards. The NGV fueling infrastructure continues to expand, though it remains strong in some areas and weak in others. Fueling stations may offer slow-fill or fast-fill facilities that can refuel vehicles in spans ranging from five minutes to eight hours. The fact that natural gas vehicles and fueling equipment have developed to the point where they feel and act just like the gasoline and diesel competition in most key areas leaves both CNG and LNG poised for a promising future, one in which natural gas isn't just a bridge fuel, but a permanent part of the fuel mix. Fuel Facts Chemical Structure: CH4   Chief Components: Comprised of hydrocarbon and nonhydrocarbon gases; principal constituent is methane Production Source: Reserves extracted from underground and offshore gas wells or in conjunction with crude oil production, or produced at landfill operations Energy Content (per gallon equivalent): 29,000 BTU Energy Ratio (relative to gasoline): 3.94 to 1 (about 25%) at 3,000 psi Physical Qualities: Stored as compressed gas (CNG) or cryogenic liquid (LNG) for vehicular use; burned in gaseous state by engine; octane rating as high as 130; CNG is odorized; virtually non-toxic; fuel composition varies according to production source Propulsion Method: Powers internal-combustion engine; also may power motor in hybrid-electric system Onboard Fuel/Power Storage: Compressed natural gas stored onboard in high-strength tanks of various materials at 3,000 to 3,600 psi; LNG stored to -260°F at atmospheric pressure Key Safety Factors: Lighter than air, so it disperses quickly in the event of a leak; if there's a leak, gas may be trapped in enclosed space, making ventilation crucial; 1,200°F ignition temperature is twice that of gasoline; cryogenically stored LNG requires special handling Advantages: Offers lower emissions of most regulated pollutants; price stability; lower fuel cost; high octane rating; extended maintenance periods and engine life mean lower life-cycle costs; fuel produced in North America; little to no performance drop-off in the newest natural gas vehicles Drawbacks: Storage is costly, bulky; station and vehicle costs relatively high; limited vehicle variety; infrastructure growing but still limited Market Status: Factory-built natural gas-powered vehicles are commercially available in all vehicle classes from most major auto manufacturers; conversion systems available to retrofit existing traditional-fuel vehicles   For More Information About Natural Gas Vehicles Alternative Fuels Data Center & Hotline U.S. Dept. of Energy Phone: 800-423-1363 Web site: www.afdc.doe.gov Association Francaise du GNV (France) Phone: +33-1-4754-3448 Australasian Natural Gas Vehicles Council Phone: +03-9899-5411 CALSTART/WESTART Advanced Vehicle Consortium Phone: 626-744-5600 Web site: www.calstart.org Canadian Natural Gas Vehicle Alliance Phone: 416-498-1994, ext. 303 Web site: www.cga.ca/cngva Clean Cities Program, U.S. Dept. of Energy Phone: 800-224-8437 Web site: www.ccities.doe.gov European Natural Gas Vehicle Association (Netherlands) Phone: +31-20-597-3100 E-mail: engva@euronet.nl Gas Research Institute Phone: 773-399-8100 Web site: www.gri.org International Association for Natural Gas Vehicles (New Zealand) Phone: +64-9-523-3567 Web site: www.iangv.org.nz Japanese Natural Gas Vehicle Forum Phone: +81-3-3502-5286 E-mail: JGA00827@niftyserve.or.jp   Natural Gas Vehicle Coalition Phone: 703-527-3022 Web site: www.ngvc.org NGV Russia Phone: +7-095-133-0570 E-mail: ngvrus@gazprom.ru NGV Systems Italy Phone: +39-51-400-357 U.K. Natural Gas Association Phone: +0171-388-7598 Web site: natural-gas-vehicles.co.uk Reprinted from Advanced Vehicle 2000, a directory of clean fuels and vehicles. For more information contact RP Publishing, Inc. at 303-863-0521, info@rppublishing.com or www.rppublishing.com Author:  David Port Reprinted with Permission by the Author or Publisher:   RP Publishing, Inc. Source :RP Publishing, Inc.   Author: David Port   Source:  RP Publishing, Inc.     Reprinted with Permission by the Author or Publisher :RP Publishing, Inc.