Hybrid bus helps put the brakes on gas use

KINGSTON — The North Kitsap School District made way for a special delivery this week.

The district became the first in Washington state to receive a hybrid school bus that uses regenerative braking technology. Transportation Director Ron Lee said the bus, made by Thomas Built Buses, should save between 300 and 450 gallons of fuel per year.

“In a year we should be able to tell if it’s going to do what it’s said to do,” Lee said. “Stop and go is what it’s designed for, and that’s what we do the most.”

Lee said most diesel-engine buses get about eight miles per gallon. He is not sure yet what kind of fuel economy to expect from the hybrid bus.

“We’re hoping it’s going to be doing a lot better,” Lee said. “I’m sure that there’s going to be a lot of people out there that are interested to see how well it does.”

The 33,000-pound vehicle arrived Wednesday morning at the district’s bus depot in Kingston. The new bus, which the district ordered nine months ago, cost $171,000 — about $81,000 more than most buses in the North Kitsap fleet. Thanks to an insurance claim on a bus involved in an accident about three years ago, the district only paid $82,000 of the hybrid’s sticker price. Over the next 13 years, the district will get even that money back.

“The state will pay us back 100 percent of the purchase price of this vehicle,” he said.

The state reimburses school districts’ transportation vehicle funds on a schedule based on how long a vehicle is supposed to last. The hybrid bus is expected to last 13 years.

Lee expects the district to be able to purchase more of the buses in the future, especially as the cost of the vehicle continues to drop. He added that the cost of the bus has actually come down from more than $200,000 in recent years.

“The more people that buy them, the more likely that that’s going to continue to drop,” he said.

In addition to the fuel savings, which could amount to as much as $1,300 per year, Lee said part of the reason for purchasing the bus was to make the district’s transportation services more environmentally friendly.

“I’m always interested in fuel reduction and the carbon footprint,” he said. “Those were the two main concerns.”

While the new bus is not the first gas-electric hybrid in the state (the Lake Chelan School District has a plug-in hybrid bus), Lee said it is the first in the state to use the regenerative braking technology.

With the regenerative technology, an electric motor/generator sits between the engine and transmission and generates electric power when the bus is in use. When the brakes are applied or the bus is coasting, that power is stored in a lithium-ion battery next to the generator. When the bus starts to accelerate again, it draws not only on the power of the diesel engine, but also on the battery power, thus using more electricity and less fuel to get going.

Another benefit Lee listed is a reduction in maintenance costs for the new bus. The regenerative technology slows the bus down more quickly and easily than the older buses. This puts less pressure on the brakes and reduces the amount of wear on them.

School bus driver Corinne Johnson, who will begin using the new bus on route 3 out of Kingston High and Wolfle Elementary in about two weeks, had a chance to test drive the bus Wednesday.

“It drives very nice,” Johnson said of the new bus. “They’ve made progress in steering radius and all that. … Which is very nice in crowded neighborhoods.”

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