The United States is introducing its first zero-emission passenger train, powered by hydrogen and batteries, which is undergoing test runs in San Bernardino. The train, named ZEMU (Zero-Emission Multiple Unit), will connect San Bernardino with Redlands, running a 9-mile route. In late June, the blue-and-white train arrived at the San Bernardino Depot Train Station for testing. Crews are currently testing the train's communications systems and safety measures at railroad crossings over the weekend. The testing phase has led to the suspension of normal Metrolink Arrow service. Passengers are advised to check alternative bus routes. The train is set to become part of Metrolink's Arrow service, providing environmentally friendly transportation between the two cities starting in early 2025. The ZEMU train uses hybrid hydrogen and battery technology, making it a significant step towards sustainability. Transit officials believe it will be the most environmentally efficient railcar in the country, with a positive outlook on its impact on public transportation and environmental efforts.