A Better Bus

Superlight Hybrid Buses Could Green the Urban Commute. By Brandon Keim

The bus.

Just two little words, yet—as any city dweller can attest—they suggest so much. Buses, especially those used for public transportation, are loud and cramped. They shake more than the clunkiest cars. Worse yet, they guzzle gas and spew pollution, boasting fuel efficiencies that make Hummers look like models of conservation.

But if a tiny company working in the ruins of America's automotive heartland has its way, all that will change. With funding from the Department of Energy and help from the Oak Ridge National Laboratories, Detroit-based Autokinetics has designed a bus that's clean, green and even comfortable.  

"We were given total carte blanche to do what we thought best," said Bruce Emmons, president of the three-man engineering design company. "It was aggressive, radical thinking."

Autokinetics started with the futuristically dubbed Nitronic 30, a high-tech stainless steel three times stronger than regular alloys. Its strength allowed Autokinetics to cut bus weight by half, reducing the gas needed to move it.

"When that started to look promising, the DOE said, ‘we don't want to just plop a big old diesel engine on it,’ and the agency gave us funding to rethink the propulsion system," Emmons said.

The Autokinetics answer: Swiss-made Zebra batteries, which can be completely drained and recharged without losing capacity. Good on their own for 150 miles, they're supplemented by a diesel engine. When the bus is stuck in traffic or boarding passengers, the batteries kick in, saving even more fuel.

"Our calculations show that it can get 12 to 16 miles per gallon. Conventional buses get like three and a half," said Jules Routbort, an Argonne National Laboratory scientist who collaborated with Autokinetics.

However, the bus is more than merely sensible. Because of its extra-strong frame, said Emmons, the bus vibrates less than both regular buses and cars, making for a smooth ride. Suspension-mounted motors replace the mechanical drivetrain, saving weight and lowering the floor, thus eliminating the step-up—so treacherous on rainy days or with an armful of bags.

Because the bus is lighter, Autokinetics was also able to use smaller wheels. These intrude minimally into the passenger space, making it roomier. Without the full-sized diesel engine normally housed in the rear, windows wrap panoramically around the back of the bus, and the glass itself is a reflective laminate that passes light but not heat.

"We paid a lot of attention to making it a more pleasant ride," said Emmons. "What good is it to have efficient buses if nobody is riding on them?"

The Autokinetics prototype is slated for completion in July 2007. Emmons said it was too early to speculate about the price of the buses, but he expected it to be competitive with, or even cheaper than, conventional buses. The price will also depend on the customer specifications that the bus must meet.

Autokinetics has talked to other companies about licensing deals, and they have have received overseas interest. Emmons hopes to crack the markets of countries like Brazil, Russia, and China, which annually purchase many more new buses than the United States.

Sustainable transportation expert Michael Millikin, editor of the sustainable transportation newsletter Green Car Congress, is optimistic about both Autokinetics and the future of green public transportation.

"Reducing greenhouse gas emissions to the level we need is going to take much more than developing fuel-efficient cars," he said. "Mass transit is going to play an important role, and the cleaner and more sustainable we can make that, the better off we are."

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I am a bus driver here at ORNL and can't understand why we can't get one of these hybrid buses to test out, lease etc. If DOE funding and ORNL is both on board! We just keep picking up VIP'S in a ten year old at best bus, to show them state of the art science. Seems to me a good first impression, would be worth a million or two at least! It would set the tone to start with, to the 21 century. Don't anyone at all agree?

Danny Castleberry

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