Skip to main content

Zero-emissions fleet

Transitioning to a zero-emissions fleet

King County Metro is leading the transit industry—and the country—by being an early adopter of a battery-electric bus fleet. Electric vehicles are quieter and produce no exhaust. Metro is moving to a 100% zero-emissions fleet powered by renewable energy with a target of 2035.

Read the transition plan (PDF)

Frequently asked questions

A zero-emissions fleet benefits the community, riders, and employees by eliminating greenhouse gas emissions and improving the quality of our air. Additionally, the program aligns with broader King County equity and social justice goals around the Strategic Climate Action Plan.

Metro operates a fleet of over 1,400 buses. Currently, there are 185 zero-emission buses, which includes 174 electric trolley buses that use overhead wires, and 11 (40-foot) battery-electric buses with charging stations at the Bellevue Base and Eastgate Park & Ride.

In 2022, an additional 40 battery-electric coaches are set to start arriving to join the Metro fleet. Produced by New Flyer, both the 60-foot and 40-foot vehicles can travel 140 miles on a full charge, tested to approximate a full passenger load.

There are two main types of charging methods: fast charging and slow charging. Fast charging, also referred to as in-route or opportunity charging, allows buses to be charged in minutes between routes and before returning to the base. Slow charging, also referred to as overnight charging, is longer and takes place at bases with charging infrastructure.

Metro is celebrating the opening of a battery-electric charging location in Tukwila that will be the initial home of our battery-electric coaches.

Metro joined only a handful of large transit agencies in the U.S. that have a fleet that does not include fully-diesel coaches with the retirement of the last diesel-only coaches in 2020.

As Metro transitions to our zero-emission future, we are also trying to ensure that we get value out of the existing fleet of diesel-hybrids, so they will continue to be in use while we develop the infrastructure needed to support our battery-electric coaches.

Metro will phase 40 zero-emissions buses into operations, starting in 2022 at our South Campus in Tukwila. The expansion will continue with a new base with charging infrastructure for 120 battery buses in 2025 and a base for 250 battery buses completed in 2027.

At launch, chargers will be located at bus bases but future enroute chargers are also expected to be deployed, allowing battery-electric bus service on longer routes. All chargers will be a mix of high power and low power, with most chargers being low power and used for overnight charging to manage the electrical load as well as lower costs.

Our 60-foot and 40-foot coaches are tested upon delivery. The 60 ft coaches are able to travel approximately 140 miles on a full charge when loaded to approximate a full passenger load. The 40-ft coaches are able to travel approximately 220 miles when charged.

Metro is working closely with local utilities to site and plan our infrastructure as well as seeking partnerships with private companies and other transit providers to ensure our infrastructure needs can be met in a cost efficient way.

The electrical infrastructure required to support battery-electric buses, including switchgears and transformers, is already deployed in other high electric-usage industries, including hospitals, large buildings, and server farms. Metro has worked with Seattle City Light on a resiliency study of the feeders to the interim base to ensure power needs can be met.

In 2017, Metro made the commitment to begin the large-scale transition of zero-emission battery-electric buses in south King County first to serve BIPOC, low-income and limited-english speaking communities that have disproportionately borne the brunt of health impacts from air pollution and are on the frontlines of climate change.

Metro is ready to move forward with the next generation coaches that are going into service in 2022. Along with future deployment of on-route charging at strategic locations, the current generation of battery-electric buses are able to meet Metro’s service needs from South Campus. Metro will continue to investigate new technologies that emerge as we continue our transition to zero-emission fleet.


  • 2004 (Completed) Metro is one of the first public transit agencies to adopt diesel hybrids.
  • 2015 (Completed) Purchases new electric trolley fleet of 174 zero-emissions trolley buses.
  • 2016 (Completed) Pilots three battery-electric fast charge buses on routes 226 and 241.
  • 2017 (Completed) Commits to move to a 100% zero-emissions bus fleet powered by renewable energy.
  • 2018-2019 (Completed) Leases and tests 10 battery-electric buses from three manufacturers.
  • 2021 (Completed) Metro orders 40 battery-electric buses with a 140-mile range for service out of South Base.
  • 2022 (Current) Metro commissions a charging test facility at South Base serving the new 40 bus fleet using equipment from three different manufacturers.
  • 2024 Metro plans to order 120 battery-electric buses.
  • 2025 Metro plans to open Interim Base at South Campus, fully electrified to operate a 120 bus fleet.
  • 2027 Opens a new South Annex Base, fully electrified to operate an additional 250 battery-electric bus purchase.
  • 2028-2035 Construct charging infrastructure at remaining six existing bases and associated layover charging on routes. Replace the remaining hybrid bus fleet.
  • 2035 Metro's goal for operating a 100% zero-emissions fleet of fixed-route buses.

Translation disclaimer