Southwest Research Institute (SwRI) has made significant strides in the development of hydrogen-fueled propulsion systems, particularly for heavy-duty vehicles. As part of the H2-ICE Consortium, SwRI successfully created a hydrogen-fueled Class 8 demonstration vehicle with an internal combustion engine that boasts ultra-low NOx and CO2 emissions, catering to the needs of heavy-duty applications. By collaborating with industry leaders from various sectors, the consortium aims to accelerate the adoption of sustainable mobility through innovative hydrogen engine technology. The focus on reducing nitrogen oxide emissions and demonstrating the compatibility of H2-ICE vehicles with other zero-emission technologies highlights the commitment to decarbonizing the transportation industry. The completion of the demonstration vehicle, featuring a powerful 370 hp engine with low emissions, marks a significant milestone in the project. SwRI's innovative approach included developing a novel aftertreatment system tailored to the hydrogen exhaust environment, further minimizing NOx emissions to near-zero levels. The successful outcomes of the H2-ICE project position hydrogen as a viable and environmentally friendly option for heavy-duty trucking, paving the way for a greener future in the transportation sector.