J-ENG marine engine reaches 95% hydrogen co-firing

Testing validates emissions reduction and stable engine performance.

The full‑scale engine intended for installation on an actual vessel, 6UEC35LSGH, has started hydrogen co-firing operation across all cylinders in factory testing, achieving more than 95% hydrogen co-firing at full load, Japan Engine Corporation (J-ENG) said.

The world-first engine is a full-scale large, low-speed, two-stroke unit intended for installation on a 17,500-DWT hydrogen-fuelled multi-purpose vessel, the company said in a press release.

The results confirm hydrogen co-firing performance, greenhouse gas reduction effects, and stable operation, and that further verification testing will continue.

The engine is being developed under the Green Innovation Fund project led by the New Energy and Industrial Technology Development Organisation, in collaboration with Kawasaki Heavy Industries, Mitsui O.S.K. Lines (MOL), MOL Drybulk, Onomichi Dockyard, and Nippon Kaiji Kyokai (ClassNK).

Kawasaki Heavy Industries is developing the hydrogen fuel supply system for the vessel, which will use liquefied hydrogen fuel.

J-ENG is scheduled to ship the engine in January 2027 for installation on the vessel, which Onomichi Dockyard is designing and building.

MOL and MOL Drybulk will operate the vessel for a three-year demonstration starting in the financial year 2028, whilst ClassNK will conduct safety evaluations throughout development, construction, and operation.