A consortium of NYK Line, IHI Power Systems, Nihon Shipyard, Japan Engine Corporation, and ClassNK have developed an ammonia-powered engine for global shipping. As part of the Green Innovation Fund Project, tests of the engine have started on the ammonia-fuelled four-stroke marine engine for the main engine of coasters, which is to be installed in a tugboat in 2024. The consortium also aims to install the auxiliary engine on an ammonia-fueled ammonia gas tanker, scheduled for delivery in 2026.
Although ammonia is considered as a potential alternative fuel for shipping due to its CO2 emissions, there are concerns about its high toxicity and potential nitrous oxide (N2O) emissions. Still, the tests of the engine performed mixed ammonia at a fuel ratio of up to 80% and measurements on exhaust gases, achieving stable operation. The amount of N2O and unburned ammonia emissions was practically zero, according to the consortium. No ammonia leakage from the systems was reported after the shutdown. Further land-based tests of the engine are to be carried out before it is installed in an ammonia-powered tug. The consortium will continue to work together to strengthen the international competitiveness of the Japanese maritime cluster, with the aim of building the world’s first ammonia-powered ships and achieving safe navigation, including by contributing to the development of international rules.