King County Metro, the public transit authority of King County, Washington, which includes the city of Seattle, will soon begin testing long-range battery-powered buses that can travel more than 140 miles on a single charge, the latest milestone toward a zero-emission fleet.

The latest models can travel nearly six times farther than the fast-charge buses Metro currently has in its fleet. At that distance, the battery-powered buses could satisfy about 70% of Metro’s bus routes, reducing air and noise pollution throughout the region.

Manufacturers will provide 40- and 60-foot battery-powered buses for the performance test. The buses will initially be operated out of Metro’s South Base in Tukwila. Metro has committed to prioritize deployment of new zero-emission buses on service operating from South King County, improving air quality and public health first in low-income and communities of color, which are most vulnerable to the public health impacts of air pollution.

Among the buses under test are four New Flyer Xcelsior CHARGE battery-electric, heavy-duty transit buses (two 40-foot and two 60-foot).

King County Metro earlier this year became the first transit agency in North America to install a high-powered charging station at a base facility where recharging is combined with cleaning and maintenance. Short-range buses at Metro’s Bellevue Base can now fully recharge in much less time, which has made operations more efficient.

Metro is now building the infrastructure needed to recharge both short- and long-range buses to achieve its goal of operating a zero-emission fleet no later than 2040. King County is working with local utilities—Seattle City Light and Puget Sound Energy—to ensure that the batteries are charged with clean, renewable energy.

Two decades ago, King County Metro pushed the manufacturing industry to produce diesel-electric hybrid buses and now operates the largest fleet of its kind in the nation. Now it is using its purchasing power to demonstrate that there is strong market demand for quieter and cleaner battery-powered buses.

Before committing fully to manufacturers, we first must take steps to test the performance of this fast-moving technology.

—Metro General Manager Rob Gannon

In July, the authors of a comprehensive study praised King County’s leadership in the transition to zero-emission fleets, quantifying the benefits of battery-powered buses: lower maintenance and operational costs, reduced noise pollution, and less greenhouse gas emissions.

King County Metro was recently named the best large transit system in North America by the American Public Transportation Association, which cited the agency’s accomplishments in transitioning to clean, renewable sources of energy.