TriMet, owner of the nation’s 11th largest bus fleet, said its first zero-emission vehicle is officially ready for primetime.

For weeks the transit agency put its first battery-electric bus through test runs in Washington County and on Portland’s west side. On Wednesday, the bus will be in service full-time on Line 62, which runs between the Sunset Transit Center and Washington Square Mall on a 13-mile loop.

Putting the all-electric bus on Portland area streets represents a milestone for the transit agency as it hopes to convert its entire diesel fleet to zero emission vehicles by 2040, a blueprint TriMet’s board approved in September.

On Tuesday, PGE and TriMet touted the bus as the first in the country “powered by wind.” There are no sails atop the bus itself, nor wind turbines, but TriMet will pay a premium to PGE to purchase renewable energy credits to give the demonstration project a greener profile.

TriMet has four additional battery-electric buses on order from New Flyer, the Winnipeg-based bus manufacturer. A second battery-electric bus is on TriMet’s property and the remaining three will arrive sometime after April. It’s unclear when they will be put in service.

Doug Kelsey, TrIMet’s general manager, said in a statement that the agency was “riding the winds of change.”

“TriMet’s commitment to a zero-emissions bus fleet by 2040 and support of wind power put the agency and our region at the forefront of a cleaner future,” he said in a statement.

TriMet received a federal grant in August 2018 to help the agency buy an additional five battery-electric buses, and in September the board approved a plan to buy up to 80 additional buses during the next five or six years, paid for through $53 million from the Legislature’s 2017 transportation funding package.

Planners estimated TriMet’s plan to ditch diesel would cost roughly $500 million.

“Zero emission transit is Oregon’s best strategy to address greenhouse gas emissions from the transportation sector that are contributing to climate change,” Brendan Finn, Gov. Kate Brown’s transportation adviser, said in a statement. He said the governor “is pursuing every avenue to reduce carbon emissions while supporting long-term economic growth, and she applauds TriMet and PGE for this groundbreaking effort.”

Meredith Connolly, Director of Climate Solutions Oregon, said the initial bus is a step forward.

“Shifting from fossil fuels to clean energy is essential to addressing the climate crisis, and it’s exciting to see TriMet begin to phase out their diesel bus fleet,” she said in a statement. “These electric buses are a tangible step toward a cleaner, more sustainable future for our region.”

TriMet is plotting a course slower than at least one of its rival agencies. Washington state’s King County Metro has said it would have an entirely zero-emission fleet no later than 2034.

Kelsey, TriMet’s leader, has said previously he would push to go quicker if possible. He left the door open to pursuing other zero-emission fuel sources like renewable natural gas or other options.

The zero-emission buses would be deployed in “predominately low-income and minority communities,” TriMet said.

All of the first five battery-electric buses will run on Line 62.

Diesel vehicles are a large contributor to carbon emissions – and TriMet buses, school buses and freight vehicles represent a significant slice of the polluters’ emitting deadly exhaust into Portland’s air. TriMet uses about 6 million gallons of diesel every year, the agency said, emitting about 57,000 metric tons of carbon dioxide into the region's air, according to its own analysis.

The battery-electric buses cut emissions by 100-140 tons per year, TriMet said, when compared to the fleet’s diesel vehicles. TriMet had just 8 hybrid diesel-electric vehicles in its fleet of roughly 670 buses as of January. The battery-electric buses reduce emissions by 75 tons annually compared to the hybrid buses.

While TriMet acknowledges its diesel buses emit harmful pollutants, it estimates its riders eliminate roughly 210,000 car trips each year by choosing transit over personal automobiles. That offsets, the agency said, the diesel emissions of its fleet by roughly 21,000 metric tons each year.

TriMet said it would pay $228.75 per month for the wind energy certificates through PGE. The agency said the energy provider buys those credits from a mix of local and national wind farms, with a minimum of one-quarter of those farms “guaranteed” to be sourced from Pacific Northwest wind farms.

-- Andrew Theen

atheen@oregonian.com

503-294-4026

@andrewtheen

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