Southwest Research Institute Unveils New Hydrogen Engine for Medium-Duty Trucks with Diesel-Like Performance

On August 9, 2024, Southwest Research Institute (SwRI) announced the successful development of a spark-ignited hydrogen internal combustion engine designed for medium-duty commercial trucks. Unlike fuel cell technology, this engine burns hydrogen directly inside the cylinders via spark ignition, generating mechanical power through pistons. Researchers began with a single-cylinder prototype, focusing on optimizing the combustion process and fuel injection strategies, before advancing to a multi-cylinder version and resolving issues related to pre-ignition and combustion stability. The engine is equipped with a turbocharger to increase air intake, delivering low-end torque comparable to that of diesel engines. It features a new intake port design, larger intake valves, and dedicated hydrogen fuel injectors to optimize the air-fuel mixture within the cylinder. Additionally, the system integrates specialized software and calibration tools to precisely control fuel injection, ignition timing, boost pressure, and air-fuel ratio.