en.Wedoany.com Reported - Japan Engine Corporation (J-ENG) has completed the manufacturing of the 7UEC50LSJA-HPSCR main engine, which will be installed on a 40,000 m³ ammonia-fueled medium-sized gas carrier operated by NYK Line, scheduled to enter service in November 2026.
The Japanese-flagged vessel is being built at Japan Marine United's Ariake Shipyard. The main engine is a 7-cylinder, 50 cm bore low-speed two-stroke engine equipped with a high-pressure selective catalytic reduction system.
J-ENG completed manufacturing of the main engine on August 30, 2025, following a five-month, approximately 700-hour full-scale test. Prior to this test program, a single-cylinder ammonia engine underwent approximately 1,000 hours of testing from May 2023 to September 2024.
Under full load and at a 95% ammonia co-firing rate, the engine's nitrous oxide emissions were approximately 3 parts per million, with greenhouse gas emissions reduced by over 90% compared to heavy fuel oil operation. Nitrogen oxide emissions were about half those of a heavy fuel oil engine, and almost no unburned ammonia was detected downstream of the SCR system.
The vessel measures 180 meters in length, 32 meters in width, and 18.45 meters in depth. Yara Clean Ammonia Switzerland signed a time charter contract with NYK Line in February 2025. The ship will also use an ammonia-fueled four-stroke auxiliary engine supplied by IHI Power Systems.
The project targets an ammonia co-firing rate of up to 95% for the main engine and at least 80% for the auxiliary engine, achieving a total greenhouse gas reduction of 80% or more for the vessel.
The development project is supported by Japan's New Energy and Industrial Technology Development Organization (NEDO) through its Green Innovation Fund. Participants include NYK Line, J-ENG, IHI Power Systems, and Nihon Shipyard, with ClassNK as a partner.
Japan Engine Corporation, headquartered in Akashi City, Hyogo Prefecture, is engaged in the development, design, manufacturing, sales, service, and licensing of UE-brand low-speed marine engines and related components. NYK Line is the shipping business division of Nippon Yusen Kabushiki Kaisha, and Japan Marine United is the shipbuilder. Yara Clean Ammonia Switzerland is a subsidiary of Yara International ASA. IHI Power Systems is the auxiliary engine supplier, Nihon Shipyard is a member of the development alliance, and ClassNK is Japan's classification society.
