The city of Honolulu is using $19.3 million in federal stimulus money to buy 20 new articulated hybrid buses.

The purchase, which will expand the city's hybrid fleet to 70 buses, allows the city to quickly deploy the stimulus money on a "green" project. However, that additional investment in hybrid buses comes despite the findings of a recent report by O'ahu Transit Services Inc. — operator of TheBus — that buying more modern diesel buses makes better financial and environmental sense than buying fewer more expensive hybrid buses.

The 60-foot hybrid electric buses, which cost nearly $1 million each, are being purchased under an option from an earlier hybrid bus order with Canadian bus maker New Flyer.

"Because the stimulus gave us the flexibility to go out and purchase some additional buses and the opportunity existed to exercise our option, we were able to get them for a good price," said city Transportation Director Wayne Yoshioka. "Because this was an exercising of an option, we were able to do it quickly and all the stimulus projects are time-driven."

In addition to the hybrid buses, which will be delivered during a two-year period, the city is in the process of buying 10, 35-foot clean diesel buses and 24, 40-foot clean diesel buses. Clean diesel buses are more environmentally friendly than older diesel buses and cost about half as much as articulated hybrid buses.

According to an April report by OTS, hybrid buses emit fewer pollutants and greenhouse gases than diesel buses. However, there is still debate over whether hybrid buses are more green than modern clean diesels. Regardless, older bus engines are substantially dirtier than modern diesel engines, so buying more modern diesel buses is better for the environment than buying a relatively small number of more expensive hybrid buses.

'AN ECONOMIC THING'

Roger Morton, president and general manager for OTS, said the transit service isn't opposed to hybrid buses.

"It's not that we don't like hybrids at all," he said. "It's purely an economic thing as far as I'm concerned."

The 20 New Flyer 60-foot buses are made primarily in Minnesota. They cost the city about $975,000 each and can seat 57 people. In contrast, a standard 40-foot clean diesel transit bus, which has 38 seats, costs the city about $395,000. The city has said the higher costs are offset by long-term fuel efficiency gains. However, the buses are not cost-effective unless fuel costs increase at a rate of 20 percent each year for 15 years, according to OTS.

At a moderate 4.6 percent annual fuel rate increase, the life-cycle costs of a hybrid bus over 15 years (including purchase, maintenance and fuel costs) was estimated to be $117,626 more than a diesel bus.

Additionally, the conversion to hybrids has led to fewer overall bus purchases in recent years and, in turn, an aging fleet, according to the report.

The hybrid bus purchase appears to meet several goals of American Recovery and Reinvestment Act transportation spending, including improving public transit and reducing greenhouse gas emissions. However, Honolulu City Council member Charles Djou has questioned whether the hybrid bus purchase would provide long-term economic and environmental benefits over clean diesel buses.

"The concern I think raised by many, myself included, was that (the federal stimulus plan) wasn't exactly the wisest way to spend the people's money and I think this is a perfect example of problems I think, not just in Hawai'i but across the country, of not the best use of taxpayer resources — just spending money to spend money," Djou said.

URBAN ROUTES BEST

Yoshioka and Morton said the city will look at using the new hybrid buses on urban routes that require frequent starts and stops. That would maximize their fuel efficiency and emission benefits. Normally the city rotates all of its buses across most routes — a practice that sometimes puts hybrid buses on routes that don't suit them.

"We are looking at trying to figure out a way to use these 20 that come in some of our heaviest, heavy-duty Downtown stops where we will get the maximum benefit," Morton said.

Whether the city will continue to buy hybrid buses after this latest order is still being evaluated and will depend on how well the new buses work. Last year, city officials said they wanted to convert half of the city's 530 buses to hybrids by 2013.

However, the April report that questioned the wisdom of buying hybrid buses is "causing us to pause and re-evaluate what we do," Yoshioka said. "We've got to make that determination. It may be that we'll say OK, should we really be spending that kind of money on our hybrids?"