MANUFACTURER Japan Engine Corporation (J-ENG) is claiming the first fully-functional full-scale commercial engine running on ammonia.
Image: Japan Engine Corporation
The 7UEC50LSJA-HPSCR design has been developed as a part of the ‘Next-Generation Ship Development of Green Innovation Fund Project’ administered by the country’s New Energy and Industrial Technology Development Organization (NEDO).
From 27-30 August at J-ENG's factory, the engine official test runs were conducted under the supervision of NYK Line, Nihon Shipyard, Japan Marine United and ClassNK. A series of performance verification tests in both ammonia fuel operation mode and heavy fuel oil operation mode as a dual-fuel engine, as well as post-operation inspections of major components, were successfully completed, and the engine's outstanding environmental performance and safety were certified by ClassNK, J-ENG says.
This engine will be shipped in October 2025 and then installed on an AFMGC (Ammonia-Fueled Medium Gas Carrier) being constructed by JMU Ariake Shipyard. The vessel is scheduled to enter service in 2026.
J-ENG previously conducted approximately 1,000 hours of test runs on a single-cylinder ammonia-fuel test engine at the Mitsubishi Heavy Industries Research & Development Center at Nagasaki between May 2023 and September 2024. Using the results and insights gained from the test, J-ENG manufactured the first full-scale commercial engine 7UEC50LSJA-HPSCR and began test runs on ammonia fuel in April 2025.
Trial run data for this engine shows that at 100% load and a 95% ammonia co-firing rate, nitrous oxide emissions are approximately 3ppm, achieving a reduction of over 90% in GHG emissions. NOx emissions were confirmed to be approximately half those of heavy oil engines, with unburned ammonia emissions virtually zero (post-NOx SCR). It has also been confirmed that the thermal efficiency in ammonia fuel operation mode is equivalent to or higher than that in heavy oil operation mode.
Following from the first engine (bore 50cm), J-ENG says it is concurrently developing an ammonia-fuelled engine with 60cm bore to address the wide variety of ammonia-fueled ships expected to emerge in the future market.
The use of ammonia as an alternative fuel is gaining traction across a number of maritime sectors, notably container ships and PCTCs, as worries grow over LNG’s contribution, as a fossil fuel, to GHGs and global warming.
Grande Shanghai. Image: Grimaldi Lines
Last week Italy’s Grimaldi took deliver of Grande Shanghai, the first of a series of 10 ammonia-ready 9,000/9,800 CEU PCTCs commissioned from China Merchants Heavy Industries Jiangsu.
And Höegh Autoliners placed a landmark order for ammonia-burning Everllence (formerly MAN Energy Solutions) B&W ME-LGIA engines.
The order is for 4 × 7S60ME-LGIA (Liquid Gas Injection Ammonia) dual-fuel engines, to be built by South Korea’s HD Hyundai Heavy Industries and fitted to the final four of Höegh’s 12 x 9,100 CEU Aurora class PCTCs, under construction in China.