Japanese shipping group NYK has started converting the tug ‘Sakigake’, currently powered by liquefied natural gas (lng), to ammonia propulsion. By mid-2024, the first tug with an ammonia engine will then sail around Japan.
An ammonia engine manufactured in Japan will be installed in the ‘Sakigake’. This was developed by NYK in close cooperation with Japan Engine Corporation, IHI Power Systems and Nihon Shipyard as part of Japan’s ‘Green Innovation Fund Project’. That is a 2 trillion yen green innovation fund that, as part of the New Energy and Industrial Technology Development Organisation (NEDO), aims to achieve climate neutrality by 2050. Some three years of intensive development preceded the construction of the ammonia engine.
Unburned ammonia
The new engine was extensively tested at IHI Power Systems’ Ohta plant in Japan. NYK wanted to make sure that no emissions of unburned ammonia and nitrogen oxide (N2O) were released. Unburned ammonia and nitrous oxide released could cause a greenhouse effect about 300 times that of carbon dioxide (CO2).
‘A tug’
To replace the entire engine, including the main engine and fuel tank, the engine room of the ‘Sakigake’ will be sawn through. After fitting the ammonia engine, the tug will be renamed ‘A-tug’. Delivery of the ‘A Tug’ is scheduled for June 2024. The vessel will continue to be operated by Shin-Nihon Kaiyosha to further monitor decarbonisation and operational safety as the world’s first ammonia-powered tug.
