Japan Engine Corporation has completed what it says is the world’s first hydrogen-fuel engine for large merchant ships, with factory tests achieving a hydrogen co-firing ratio of more than 95% and cutting GHG emissions by more than 95% compared with a conventional heavy-fuel-oil engine, according to a ClassNK statement.
The 6UEC35LSGH engine was unveiled at Japan Engine’s head-office plant on 7 September after completing approval testing witnessed by ClassNK. It uses high-pressure direct hydrogen injection and incorporates a hydrogen-leak prevention structure and double-walled hydrogen supply piping.
The engine is scheduled to be installed in January 2027 on a 17,500-dwt multipurpose ship being built by Onomichi Dockyard for Mitsui O.S.K. Lines and MOL Drybulk under the Blue Harmony project.
Hydrogen will be supplied by a marine hydrogen fuel system developed and manufactured by Kawasaki Heavy Industries, consisting of a hydrogen fuel tank and fuel supply system. Kawasaki is also developing equipment to bunker liquefied hydrogen into the vessel.
Sea trials will be followed by full-scale shipboard demonstration testing from April 2028, including checks of durability under operating conditions. ClassNK will assess safety during development of the engine and through the ship’s design, construction and operation.
The work is part of NEDO’s Green Innovation Fund programme for next-generation ships. Japan Engine, Kawasaki Heavy Industries and Yanmar Power Solution are developing the marine hydrogen engine and fuel system.