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King County Metro Hybrid Electric Buses

From 2004 to 2006, the Fleet Test and Evaluation team worked with King County Metro Transit to study the performance of 10 60-ft hybrid electric transit buses manufactured by New Flyer Industries and equipped with Allison Transmission hybrid propulsion systems.

Photo of a King County Metro articulated hybrid electric bus

King County Metro Transit deployed 60-foot buses propelled by Allison Transmission hybrid electric propulsion systems.

The 12-month evaluation focused on 20 diesel and hybrid diesel buses at three of the transit agency's seven depots. King County Metro Transit services the Seattle area, transporting about 100 million passengers each year. Its fleet of 1,300 buses, trolleys, and streetcars includes more than 230 hybrid electric buses.

The results of this study are featured in King County Metro Transit Hybrid Articulated Buses: Final Evaluation Results.

Additional information on King County Metro Transit is available on the Hybrid Electric Drive Systems Publications page.