The transportation industry is increasingly turning to alternative engine solutions to combat climate change. While electric vehicles have been popular, hydrogen engines are gaining traction, especially for long-haul vehicles. Japanese companies like Toyota and Hyundai are making significant strides in hydrogen fuel-cell technology. Despite challenges in consumer adoption, Toyota aims for zero emissions by 2050 using hydrogen technology. The Southwest Texas Research Institute (SwRI) has developed a hydrogen internal combustion engine for heavy-duty trucks, offering a practical zero-emission solution. This innovation promises higher efficiency, lower carbon emissions, and a combination of hydrogen, electricity, and water for power. Hydrogen engines operate through a chemical reaction that produces only water as a byproduct, emphasizing their potential in diversifying engine solutions for a sustainable future.