Carbon Footprint of Hydrogen-powered Inland Shipping: Impacts and Hotspots

The shipping sector is facing increasing pressure to implement clean fuels and drivetrains. Especially hydrogen fuel cell drivetrains seem attractive. Although several studies have been conducted to assess the carbon footprint of hydrogen and its application in ships, their results remain hard to interpret and compare. Namely, it is necessary to include a variety of drivetrain solutions, and different studies are based on various assumptions and are expressed in other units. This paper addresses this problem by offering a three-step meta-review of life cycle assessment studies. First, a literature review was conducted. Second, results from the literature were harmonized to make the different analyses comparable, serving cross-examination. The entire life cycle of both the fuels and drivetrains were included. The results showed that the dominant impact was fuel use and related fuel production. And finally, life-cycle hot spots have been identified by looking at the effect of specific configurations in more detail. Hydrogen production by electrolysis powered by wind has the most negligible impact. For this ultra-low carbon pathway, the modes of hydrogen transport and the use of specific materials and components become relevant.