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May 15, 2007

Hybrid buses fuel effort to save gas, help environment

WEST LAFAYETTE, Ind. - Purdue University students and staff who use the CityBus public transportation system will be playing an even bigger part in helping the environment.

Two years ago, CityBus ordered two new hybrid buses to replace aging models. The hybrids arrived in March, and campus and transportation officials say the buses are not only burning less fuel, but they're also sending fewer emissions into the air.

"The less fossil fuel we burn, the better it is for the environment," said Kumares Sinha, Olson Distinguished Professor of Civil Engineering. "CityBus is to be commended for the initiative. This is one step, but it's a big one. Anything we can do to get the momentum going toward saving fuel and the environment helps. If all of us make a concerted effort, one day there will be a positive impact on the environment."

CityBus provides public transportation in Lafayette and West Lafayette with its fleet of 67 buses, about 30 of which service Purdue. CityBus carries 4.3 million passenger trips annually, and the Purdue campus accounts for about 70 percent of the ridership. Purdue pays nearly $1.3 million annually, which covers the operation of the campus loop system and unlimited riding privileges for students, faculty and staff.

The two new hybrids use electric power during rolling starts and as they start. In between, at drive speeds, the buses are diesel-fueled.

"In an old bus, you'd see that big puff of smoke as they take off to get going," said Mike Jasper, Purdue's financial manager of utilities. "The new bus uses the electric motor to accelerate, then switches over to the diesel so that we don't have that big puff of emissions. The batteries are recharged during deceleration, using the momentum of the bus to generate electricity."

The hybrids make less noise and don't cause as much wear and tear on the engine and brakes, as well. However, the key is the fuel savings, which also plays into the healthier environmental impact.

"Our main objective was to improve the fuel economy of the buses," said Jon Fricker, a professor of civil engineering at Purdue and a member of the CityBus board of directors. "The standard diesel bus gets about four miles to the gallon. That's nationwide and pretty standard.

"Hybrid buses are getting between five and six miles a gallon, which doesn't sound like much, but that's a huge percentage increase. If you're burning less fossil fuels, you're going to have fewer pollutants that come from the internal combustion engine. We travel the same miles, but we're burning less fuel."

The buses were made possible through federal funding. U.S. Sen. Richard Lugar of Indiana and Congressman Steve Buyer, both worked on securing funds. Buyer, who represents the Lafayette areas, was able to earmark $2.5 million in the reauthorization bill. CityBus was able to use part of those funds for the buses.

Marty Sennett, general manager for CityBus, received an Energy Patriot of the Month honor from Lugar, who picks a Hoosier each month to recognize for trying to lessen the dependence on foreign oil.

Sinha said he is pleased that CityBus and Purdue have taken a lead in helping the environment.

"The buses are more expensive, but looking at the total picture, this is a good thing to do - not just for the money, but for the social benefits as well," he said.

Fricker said CityBus already has talked about its next round of bus purchases, and more hybrids will be on the way.

"The early indications from the hybrid buses are that they are working very well," he said. "We just thought we'd continue on that path."

Writer: Jim Bush, (765) 494-2077,

Sources: Jon Fricker, (765) 494-2205,

Kumares Sinha, (765) 494-2211,

Mike Jasper, (765) 494-3881,

John Metzinger, (765) 423-2666,

Purdue News Service: (765) 494-2096;

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