News of February 20, 2002
Allison Transmission Showcases "Home-Grown" Hybrid Vehicle Technology
INDIANAPOLIS - When a transit bus parked on Ohio Street north of the Statehouse starts its engine to transport Indiana legislators to view new "clean," fuel-saving vehicle technologies, one thing will be absent--a large black cloud from the exhaust pipe.
That's because the bus is powered by a clean hybrid technology from the Allison Transmission Division of General Motors (GM). It is a technology that brings dramatically lower emissions and improved fuel economy to commercial-duty truck and bus applications.
The bus is on hand today as part of an Allison-hosted event that will give Indiana legislators a first-hand look at Indiana-developed hybrid technologies.
State elected officials from the legislative and executive branches will ride to the event at Marriott Hotel Downtown on the 40-foot hybrid transit bus powered by the Allison Electric DrivesTM EP SystemTM. One of the first "roadworthy" commercial parallel hybrid systems, an earlier generation of the Allison system now powers buses for the Orange County Transportation Authority (OCTA).
"The parallel hybrid electric system is the most efficient hybrid architecture available today," said Larry Dewey, president of Allison Transmission. "In addition to bringing the benefits of hybrid electric technology to commercial vehicles, the EP System is helping establish hybrid technologies as effective, practical and commercially viable. This system stands ready to revolutionize transportation as we know it."
Allison Transmission's EP SystemTM offers a range of benefits. The system can be easily adapted to fit into existing vehicle platforms and delivers about 60 percent better fuel economy than a conventional diesel system in urban transit bus applications. Buses equipped with the EP SystemTM produce much lower hydrocarbon and carbon monoxide emissions than conventional diesel buses, lowering particulate emissions (tiny pieces of soot and dust) by 90 percent and NOX emissions (nitrogen oxide) by 50 percent. Buses equipped with the Allison Electric DrivesTM system also deliver 50 percent better acceleration than a bus equipped with a conventional diesel powertrain.
Here's how hybrid technology works: Hybrid systems use two sources of power to move a vehicle - engine and battery. In the parallel hybrid system, the engine-generator combination works in parallel with the battery, furnishing electrical power to keep the battery charged. The engine is coupled to a drive unit that furnishes an infinitely variable ratio to the wheels. This allows an engine in a hybrid system to run more efficiently, quietly and cleanly. For example, when the bus accelerates from a stop, the batteries can supply a powerful acceleration. This eliminates the excessive diesel cloud that an accelerating bus typically emits. A hybrid bus uses the diesel engine to maintain speed after the vehicle is underway. In this mode the engine also charges the electric power source, making the vehicle capable of self-sustaining mobility.
The Allison Electric Drives EP SystemTM brings the benefits of advanced hybrid technology to a broad class of commercial transit and trucking applications. The EP SystemTM is designed to bring the "hybrid advantage" to vehicles such as articulated buses, suburban coaches, military vehicles and medium- and heavy-duty trucks. Designed in a compact, standardized platform that enables integration across a range of commercial vehicle types, the EP SystemTM is compatible with existing vehicle architectures. The EP SystemTM also is flexible and is easy-to-scale to a broad range of commercial applications.
"Allison's EP SystemTM represents an important success in taking advanced hybrid solutions from experimental to commercially viable technologies, utilizing groundbreaking, state-of-the-art development techniques," said Fred Cartwright, program director, Allison Electric Drives. "By leveraging the benefits of GM's advanced technologies, Allison Transmission will continue to develop the type of environmentally responsible, viable and sustainable hybrid propulsion systems that today's commercial applications need."
In 1999, Allison successfully completed a demonstration hybrid bus program for the New York City Transit (NYCT) Authority. In 2000, the company began its hybrid electric "Preview" program. This "first generation hybrid" program, the first step of which was undertaken with New Flyer of America, is bringing hybrid electric buses to transit systems across North America. California's Orange County Transit Authority (OCTA) was the first transit property to place Allison-powered hybrid electric buses into revenue service in 2000. Allison plans to deliver up to 13 hybrid systems to transit operators nationwide in 2002.
(February 20, 2002)