King County Metro, based in Seattle, is shifting its fleet electrification strategy to include hydrogen-powered buses alongside battery-electric buses. The sudden change comes as the agency faces challenges with battery bus technology, leading them to explore alternative options for achieving a zero-emissions fleet by 2035. Metro intends to trial up to four hydrogen fuel cell buses by 2026 to assess their performance, particularly in terms of range and suitability for all-day routes. This decision marks a significant departure from their previous focus on battery-electric and electric trolleybuses. The move towards hydrogen buses is driven by operational needs and constraints experienced with battery-electric buses, such as range limitations and variability, especially in colder climates. The agency, in partnership with other transit entities, aims to leverage hydrogen technology to enhance its public transit service while advancing sustainability goals. While battery-electric buses remain a key component of Metro's electrification plan, concerns raised in a report by the King County Auditor's Office about reliance on this technology, including manufacturer shortages and performance issues, have prompted the agency to diversify its approach. The auditor's report highlighted risks associated with Metro's current reliance on two manufacturers in the North American market for battery-electric buses, as well as reliability challenges faced with the existing fleet. Metro's decision to incorporate hydrogen buses into its pilot program reflects a strategic shift towards a more diversified and resilient fleet electrification strategy. By testing and evaluating hydrogen fuel cell buses alongside battery-electric options, the agency aims to ensure a reliable and sustainable public transit system for the future.