Southwest Research Institute (SwRI) has developed a hydrogen-fueled internal combustion engine, the H2-ICE, that offers ultra-low nitric oxide (NOx) and carbon dioxide (CO2) emissions while maintaining sufficient torque and power for heavy-duty applications. The project, part of SwRI's H2-ICE consortium, involved converting a Cummins X15N natural gas engine to run on port-injected hydrogen. The consortium, established in 2022, aims to promote sustainable mobility by leveraging cutting-edge hydrogen engine technology. The engine achieved industry-leading NOx emissions, meeting stringent environmental standards. SWRI's innovative after-treatment system further reduces NOx emissions, setting a new standard in the industry. With a focus on decarbonization and zero-emission transport, the H2-ICE engine is a significant advancement for the trucking industry, offering high performance with minimal environmental impact.