They look like regular cars, and they drive like regular cars. But when you look closer, there's something profoundly different about the minifleet of mid-size sedans operating out of Building 12 at the Applied Physics Laboratory: The three cars run on natural gas.

"That was our main goal--making these cars indistinguishable in range, performance and trunk space from their gasoline-fueled counterparts," says John Wozniak, who heads APL's Advanced Natural Gas Vehicle program.

APL's natural gas-powered vehicles and the team that developed them, from the left: John Wozniak, Rich Hildebrand, Paul Wienhold, Kurt Ruckelshaus, Alicia Combs, Geoffrey Wright, Gary Peck, Mike Schoolman and Bob Wright. Not shown: John Ecker.

The ANGV program has been sponsored by the U.S. Department of Energy's Office of Advanced Automotive Technologies since 1992. To achieve ANGV program objectives, APL assembled and has worked closely with an industrial team that includes Chrysler Corp., Lincoln Composites, Goodyear Tire and Rubber Corp., Siemens Automotive, Chesapeake Automotive Enterprises, Craig Naff Inc. and Hegedus Aluminum Industries Inc.

Wozniak says that despite the current glut of oil, there is growing pressure to develop truly competitive alternative-fuel vehicles. "Worldwide vehicle use is escalating, and the United States produces only half the oil it consumes--two factors that dictate protection of American oil interest abroad. In addition, vehicle emissions affect our health and they contribute to global warming," he says.

According to Wozniak, natural gas is the most abundant source of energy on the planet. "It's virtually ready to use as it comes from the earth, and it produces ultra-low emissions." And, he adds, a vast pipeline infrastructure for distributing natural gas to homes and industries is already in place, requiring only compressor stations to make it available as compressed natural gas for vehicle use.

Vehicles have run on CNG since the 1930s, and thousands of them are on the road every day. But because of limited driving range and trunk space, natural gas-powered autos have been restricted to taxis, police vehicles and other niche fleets.

Based on a 1998 Plymouth Breeze and the equivalent Dodge Stratus sedan, the ANGV prototype cars demonstrate technologies needed to mass-produce natural gas automobiles for popular everyday use. Besides having the driving range, performance and trunk space comparable to those of gasoline-powered cars, they meet California's stringent ultra-low emission standard.

"We used a systems approach to solve tough design and manufacturing problems in three areas: the engine, storage space and chassis packaging," Wozniak says.

The cars use a Chrysler 2.4-liter power plant that's been modified with custom pistons and a state-of-the-art gaseous fuel injection system to achieve high mileage, excellent performance and ultra-low emissions with natural gas. The Integrated Storage System, developed by APL and Lincoln Composites, carries the CNG equivalent of 12 gallons of gasoline and has been rigorously tested to meet all federal and industry safety standards. The chassis design includes a lightweight, semi-trailing arm rear-suspension system and "run-flat" tires to create more undercarriage space for the CNG storage system.

"The chassis design was developed with the idea of demonstrating a common platform for mass-producing either natural gas- or gasoline-powered automobiles," Wozniak says.

In September, APL was invited to Annapolis by the Maryland Energy Administration to demonstrate one of the ANGV cars during "Maryland Energy Efficiency Month," which featured installation of a CNG fueling station for the city's new, clean-running CNG trolley.

Wozniak says the next step is to evaluate the cars in normal everyday driving conditions. Next spring, the vehicles will enter the laboratory's auto pool, and data will be collected on driving range, utility, performance and exhaust emissions. "We'll be generating valuable information for automakers, government officials and transportation planners," Wozniak says.

APL is working with the Maryland Energy Administration to explore ways to participate next summer in the Clean Cities program for the Baltimore-Washington corridor. Wozniak says that extending the ANGV prototype driving experience outside APL's own evaluations will add critical, impartial data on these alternative-fuel vehicles.