DRIVE TIME

By Mike Leidemann
Advertiser Staff Writer

Honolulu's new hybrid electric-gas buses are cleaner and quieter than the old diesel models — but that doesn't necessarily mean they are more fuel efficient.

When the new buses were unveiled here late last year, city officials said they were expected to provide about a 50 percent savings in fuel costs.

But that doesn't appear to be the case.

The New York Times reported last week that hybrid buses like those in Honolulu are providing far less fuel efficiency than the manufacturer, General Motors, had predicted.

While bus officials in Honolulu say it's still too early to tell how well the buses are doing here, transit officials across the nation said the buses with GM power trains generally save only 10 percent to 20 percent in fuel costs.

At those rates, the buses are unlikely to generate enough savings to pay for their cost, which is sometimes as much as $200,000 over standard buses, transit managers told the paper.

While hybrid automobiles are increasingly popular and some hybrid buses are proving successful, it turns out that not all hybrids are equal.

The General Motors buses use a technology called "parallel" hybrid in which the engine and the electric motor turn the wheels simultaneously. The other technology, called "series" hybrid, uses a system in which all the power to the wheels comes from an electric motor. That's the one proving more efficient.

Still, that doesn't mean transit officials are down on the GM hybrids. Many were chosen more for their clean-air technology than fuel savings. Bus riders and pedestrians say they enjoy not seeing the great clouds of dark smoke that come with more traditional diesel buses.

The 10 Honolulu buses, which cost about $750,000 each, are being used on the city's new E-transit line running from Kaka'ako to Waikiki. However, Mayor Mufi Hannemann has vowed to send the buses out to the suburbs, saying that he'll shut down the new line and let customers on longer routes get the pleasure of using them.

In a way, the bus dispute mirrors what's happening with hybrid technology around the country, where there's still a great divide between those who yearn for smaller, cleaner vehicles and those who cling to the American dream of power cars.

While the Toyota Prius and Honda Insight, which get up to 55 mpg, are rapidly increasing sales, American automakers are still pushing ever more powerful cars with far less fuel efficiency.

At the Detroit Auto Show, which opened yesterday, the big buzz was all about the new Corvette Z06, which Chevrolet says is the "fastest, most powerful car" it has ever offered, going from zero to 60 mph in less than 4 seconds with a top speed of more than 190 mph.

GM also introduced the Cadillac STS-V, a souped-up version of the STS luxury sedan rolled out last year. The STS-V features Cadillac's most powerful engine.

All that comes on top of last year's surprise money-making hit for American automakers, the Chrysler 300, which this year will feature a 6.1-liter, 425-horsepower V-8 engine.

The Associated Press contributed to this report. Reach Mike Leidemann at 525-5460 or mleidemann@honoluluadvertiser.com .