BAE SYSTEMS Announces Hybrid Electric Buses Demonstrate Superior Performance in Independent Emissions Test
JOHNSON CITY, N.Y.--Oct. 26, 2001--Independent emissions tests on transit buses show that diesel-electric hybrid propulsion is much cleaner than modern diesel power and on par with compressed natural gas (CNG).The tests evaluated such emissions components as nitrogen oxides, particulate matter, greenhouse gases, and carbon monoxide.
The hybrid buses also are far more efficient, delivering as much as 50 percent more miles per gallon of fuel than the other technologies when operated in stop-and-go conditions.
"These test results demonstrate that a system combining a modern diesel engine, an electric propulsion system, and advanced controls can match any other clean technology commercially available today," said James Scanlon, president of BAE SYSTEMS Controls, producer of the HybriDrive(TM) propulsion system that was the subject of the testing.
The system was tested aboard an Orion VII 40-foot low-floor bus, the model chosen by MTA New York City Transit for a 325-unit fleet of hybrid buses. The New York buses, currently being built, will comprise North America's largest fleet of production hybrids.
Independent testing was performed by Environment Canada, the environmental protection agency of the Canadian government, using a chassis dynamometer. Data were recorded on the Central Business District cycle (CBD-14). Emissions and fuel economy are duty-cycle dependent.
The Environment Canada findings are shown below, alongside recent data from tests on similarly sized, late-model diesel and CNG buses conducted by West Virginia University.
| -- | Nitrogen oxide pollutants from the hybrid bus measured 13.3 grams per mile, versus 30.1 grams from diesel and 14.9 grams from compressed natural gas. |
| -- | Particulate-matter emissions from the hybrid measured 0.01 grams per mile, compared to 0.24 grams from the diesel and 0.02 grams from CNG. |
| -- | Carbon monoxide pollutants from the hybrid bus measured 0.08 grams per mile, versus 3 grams from the diesel and 12.7 grams from CNG. |
| -- | Emissions of greenhouse gases -- believed to contribute to global warming -- measured 1,820 grams per mile from the hybrid bus, compared to 2,779 grams from the diesel bus and 2,708 grams from the CNG bus. |
The test also measured fuel economy, with the hybrid bus delivering 5.3 miles per gallon compared to 3.5 mpg for diesel and 3.1 equivalent mpg for CNG.
Over its lifetime, a hybrid bus would emit about 7 fewer tons of nitrogen oxides, 185 fewer pounds of particulate matter, and 390 fewer tons of carbon dioxide (or greenhouse gases). It also would save about 36,000 gallons of diesel fuel.
The HybriDrive(TM) propulsion system uses an AC induction motor to turn the vehicle's drive wheels. The diesel-driven generator supplies propulsion power to the electric motor and recharges the vehicle's battery pack.
In addition to lower emissions and improved efficiency, the configuration also offers better acceleration, providing maximum torque at zero speed and delivering power directly to the drive axle, with no energy lost through a mechanical transmission.
Reduced vehicle maintenance offers even greater potential for cost savings. No transmission means no transmission maintenance -- a major consideration on any stop-and-go vehicle -- and brake wear is reduced through a "regenerative braking" system that uses the drive motor to slow the vehicle and generate additional electricity to charge the batteries.
BAE SYSTEMS Controls, an operating unit of BAE SYSTEMS North America, is a leading supplier of electronic flight and engine controls for defense and commercial aircraft and launch vehicle applications.
It also provides integrated avionics for aircraft applications and complete unmanned aerial vehicle systems and is a leader in electronic controls for the locomotive industry and the emerging hybrid-electric vehicle market. Controls operates facilities in Johnson City, N.Y.; Santa Monica and Ontario, Calif.; Fort Wayne, Ind.; and Redmond, Wash.
About BAE SYSTEMS:
BAE SYSTEMS North America employs 22,000 people in the design, development, integration, manufacture, and support of a wide range of advanced aerospace products and intelligent electronic systems for government and commercial customers.
BAE SYSTEMS is the truly global systems, defense, and aerospace company. BAE SYSTEMS employs some 100,000 people in eight home markets around the world and has annual sales of around $18 billion. The company offers an unrivaled global capability in air and on sea, land, and space with a world-class prime contracting ability supported by a range of key skills.
BAE SYSTEMS designs and manufactures civil and military aircraft, surface ships, submarines, space systems, radar, avionics, communications, electronics, guided weapon systems, and a range of other defense products.