Japan Engine Corporation (J-ENG) has completed land-based testing of a hydrogen-fuelled engine it describes as the world’s first of its kind for large commercial vessels, according to Ship & Bunker.
The low-speed two-stroke engine, designated the 6UEC35LSGH, achieved a hydrogen co-firing rate of at least 95% during factory testing, Ship & Bunker reports, citing a joint press release from J-ENG and its project partners issued Friday. The company said this resulted in greenhouse gas emissions more than 95% lower than those produced by a conventional heavy fuel oil engine.
According to the report, approval testing took place in the presence of classification society ClassNK, with the engine presented to project stakeholders at J-ENG’s headquarters factory on September 7.
How the Engine Achieves Stable Combustion
J-ENG attributes the engine’s stable hydrogen combustion to a high-pressure direct injection system that delivers fuel directly into the cylinder, Ship & Bunker notes. Safety measures reportedly include a structure designed to prevent hydrogen leakage along with double-walled piping on the hydrogen supply lines.
Installation and Project Timeline
The engine is scheduled for installation in January 2027 aboard a 17,500 DWT multipurpose vessel currently under construction at Onomichi Dockyard for Mitsui O.S.K. Lines (MOL) and MOL Drybulk, according to the report. Onboard demonstration testing is planned to begin in April 2028, following sea trials.
Ship & Bunker reports that Kawasaki Heavy Industries is developing the marine hydrogen fuel system, comprising tanks and fuel supply equipment, that will deliver hydrogen to the engine. Kawasaki will also develop and manufacture bunkering equipment for supplying liquefied hydrogen to vessels.
The initiative forms part of the Blue Harmony project, funded through the Green Innovation Fund administered by Japanese state agency NEDO. Under this project, J-ENG, Kawasaki, and Yanmar Power Solutions are jointly developing marine hydrogen engines, according to the report. Ship & Bunker also notes that this development follows J-ENG’s completion of its first commercial ammonia-fuelled two-stroke engine in August 2025.
Does This Matter to You?
This development may be relevant to those tracking alternative marine fuel technologies and vessel newbuild programmes, particularly as hydrogen-fuelled propulsion moves from concept toward a scheduled commercial installation. Parties monitoring emissions compliance pathways and future bunkering infrastructure requirements, including liquefied hydrogen supply equipment, may find the timeline for onboard demonstration testing and the involvement of classification society ClassNK useful for tracking regulatory and technical progress in this area.
The source material does not provide details on cost, fuel availability, or broader commercial rollout plans beyond this single vessel project, so the wider operational or market impact is not yet clear.
Gulf Bunkering does not provide operational or security guidance. This article is for informational purposes only. Operators should consult flag state authorities, P&I clubs, and relevant advisories for decisions relating to transit planning.
Sources: Ship & Bunker
