Pictured is a New Flyer Xcelsior hybrid-electric 40-foot transit buses ordered by the Phoenix Public Transit Department. New Flyer is using propulsion agnostic engines to allow the company to sell buses regardless of federal subsidies, or lack of subsidies, for zero-emissions buses.

Walmart employees look over an X15N engine — made at the Cummins Inc. Jamestown Engine Plant — during a 2023 trial run.