Comparative life cycle assessment of hydrogen internal combustion engine and fuel cells in shipping

The vital role of the maritime sector in supporting global trade highlights the need for sustainable progress. The success of decarbonization depends on new technologies and using alternative fuels, with hydrogen showing great potential. Despite the prevalent focus on hydrogen fuel cells (H₂FC) in shipping applications, the potential of onboard hydrogen internal combustion engine (H₂ICE) applications remains relatively unexplored. This study endeavors to conduct a comparative life cycle assessment of the H₂ICE, H₂FC, and diesel engines of a passenger vessel. The findings demonstrate both hydrogen-powered systems exhibit notable environmental superiority compared to diesel engines, yielding 84–87% reductions in Global Warming Potential (GWP), 58%–73% reductions in eutrophication, 34%–52% reductions in acidification, etc. Furthermore, H₂ICE presents advantages over H₂FC regarding GWP and Abiotic Depletion Potential (elements and fossil). This study emphasizes the importance of extensively exploring hydrogen-powered systems for ships and their potential use in the shipping industry, highlighting the promise of H₂ICE as a key contribution.