Hydrogen (Hâ‚‚) is a zero-carbon energy carrier that can be used as a marine fuel in fuel cells or in adapted combustion engines. Onboard, it is stored either as compressed gaseous hydrogen or as liquefied hydrogen:
Gaseous hydrogen is stored at high pressure (typically 350–700 bar) in composite tanks. While simpler to handle, it has a very low volumetric energy density, requiring large storage volumes and thereby limiting range.
Liquid hydrogen is produced by cooling hydrogen to approximately −253°C, which significantly increases energy density by volume and enables a longer range. It does, however, require cryogenic storage, insulation, and boil-off management systems.
Owing to its low density and associated storage challenges, hydrogen is currently most relevant for short-sea shipping and ferries. It also serves as a feedstock for other hydrogen-based fuels, such as ammonia and methanol.
Main risks
High flammability and explosion risk: Hydrogen has a very wide flammability range and a low ignition energy, making it highly susceptible to ignition. It burns with a fast flame speed, and leaks can give rise to jet fires or explosions, particularly in confined spaces.
Leakage and dispersion characteristics: As the lightest element, hydrogen disperses rapidly in open air, but it can accumulate beneath ceilings or in enclosed ship spaces, creating concealed explosion risks. Leak detection is further complicated by the gas being odourless and by its nearly invisible flame.
Skuld's experience
The world's first liquid-hydrogen-powered vessel MF Hydra, a passenger ferry operated by member NORLED, is in service in Norway. Skuld, together with the broader insurance market, was invited to visit the vessel in 2026. To learn more about the visit and the insights gained, please contact our Decarbonisation team.