World's First Hydrogen-Fueled Engine for Large Commercial Vessels Begins Land-Based Testing

Japan Engine Corporation (J-ENG) and Kawasaki Heavy Industries, Ltd. (KHI) are working on the 'Green Innovation Fund Project / Development of Marine Hydrogen Engines and MHFS (Note 1)' under the New Energy and Industrial Technology Development Organization (NEDO), with the cooperation of Mitsui O.S.K. Lines, Ltd. (MOL), MOL Drybulk Ltd., Onomichi Dockyard Co., Ltd., and ClassNK.

In this project, J-ENG is developing a purely domestic, large, low-speed, two-stroke hydrogen-fueled engine. The company has now commenced full-cylinder hydrogen co-firing operation on the first full-scale engine (the actual engine to be installed on a ship, 6UEC35LSGH), a world-first (Note 2). To date, the engine has reached a hydrogen co-firing rate of over 95% at 100% load, confirming both GHG reduction and stable operation. Verification testing to optimize performance during hydrogen co-firing will continue.

While the development and demonstration of hydrogen-fueled ships have been progressing globally, most have focused on short-distance, short-duration, and low-output operations, such as sightseeing boats or tugboats using compressed hydrogen. In contrast, this project is characterized by a propulsion system that combines a high-efficiency, high-output low-speed two-stroke hydrogen engine (6UEC35LSGH) with liquefied hydrogen fuel, enabling long-distance, long-duration, and high-output operation. This represents a critical technical step toward the practical application of hydrogen-fueled large commercial vessels.

J-ENG has previously conducted fundamental tests on hydrogen-related materials and combustion, as well as durability tests for hydrogen fuel injection systems, incorporating these findings into the engine's development. Following various verification tests as a full-scale engine, it is scheduled to be shipped in January 2027 and installed as the main engine for a 17,500-deadweight-ton hydrogen-fueled multipurpose vessel, which is being designed and built by Onomichi Dockyard as a demonstration ship. The MHFS, the system that supplies hydrogen fuel to this engine, is being developed and manufactured by KHI and will also be installed on the vessel.

MOL and Onomichi Dockyard have agreed on the construction of this vessel and have signed the relevant contracts. Furthermore, through discussions among the involved parties, agreements have been reached on various equipment specifications for the hydrogen-fueled ship, and related contracts have been signed. Detailed design of the vessel is currently progressing smoothly.

The vessel is scheduled to undergo demonstration operations for three years starting in fiscal year 2028, under the management of MOL and MOL Drybulk. ClassNK will provide safety assessments throughout the development of the engine and MHFS, as well as the design, construction, and operation of the demonstration ship. Supported by NEDO, J-ENG and KHI, in collaboration with MOL, MOL Drybulk, Onomichi Dockyard, and ClassNK, will continue to pioneer a sustainable future for the maritime industry through the challenge of realizing practical hydrogen-fueled commercial shipping.