Japan Engine Corporation (J-ENG) has unveiled the world’s first commercial ship engine that runs on ammonia, marking a major milestone in environmentally friendly maritime technology. The engine is expected to reduce greenhouse gas emissions by up to 90 percent, offering a cleaner alternative to traditional marine fuels.

The 7UEC50LSJA-HPSCR engine operates on both ammonia and heavy fuel oil, giving shipping companies the flexibility to gradually switch to greener energy while maintaining reliable operations. This initiative is part of Japan’s Green Innovation Fund Project, aimed at advancing sustainable technologies in the shipping industry.

After more than 1,000 hours of testing, the engine has proven its efficiency and safety, achieving a 95 percent ammonia co-firing rate at full load and significantly lowering nitrogen oxide and other emissions. Built-in monitoring systems ensure that ammonia is handled safely, protecting both crew and the environment.

The engine is set to be installed on an Ammonia-Fueled Medium Gas Carrier (AFMGC) in October 2025, its first commercial deployment. The operation will provide practical insights into its performance and help pave the way for future ammonia-powered vessels.

J-ENG is also developing a larger ammonia engine, expected to start operations by 2028, aiming to meet rising demand for clean marine propulsion. By leading the shift toward ammonia-based fuel, J-ENG is positioning itself at the forefront of sustainable shipping, potentially inspiring wider adoption of low-emission technologies across the industry.