NYK inks deal to convert LNG-fueled tugboat to ammonia

Green Marine

August 9, 2022, by Jasmina Ovcina Mandra

Ammonia tug design — Ammonia Tug design/Source: NYK

Japanese shipping major NYK is pushing forward with plans to convert its LNG-fueled tugboat Sakigake to operate on ammonia fuel.

The tugboat, operated in Tokyo Bay by NYK Group company Shin-Nippon Kaiyosha Corporation, is scheduled to be converted by 2024. The fuel modification contract has been signed with Keihin Dock Co., an NYK Group company.

The tugboat was delivered to NYK in 2015, and features dual-fuel engines that can use either LNG or diesel oil, depending on conditions. Compared with conventional tugboats that use marine diesel oil, Sakigake emits about 30 percent less carbon dioxide, 80 percent less nitrogen oxide, and no sulfur oxide when using LNG as fuel, according to NYK.

LNG-fueled tugboat Sakigake; Source: NYK

According to NYK, the research and development work was launched in October 2021 in cooperation with IHI Power Systems Co. (IPS). The project was adopted as part of the Green Innovation Fund program within Japan’s New Energy and Industrial Technology Development Organization (NEDO) for the development of vessels equipped with a domestically produced ammonia-fueled engine.

Being a carbon-neutral fuel, ammonia holds the promise for the establishment of a zero-emission shipping industry. Namely, during the combustion of ammonia, there is no CO₂ emission and throughout the fuel life cycle, it can use CO₂-free hydrogen as a raw material.

“By using ammonia as a fuel for ships, it will be possible to significantly reduce greenhouse gas (GHG) emissions during voyages. Therefore, NYK and IPS are proceeding with research and development aiming for early social implementation,” NYK said.

The Japanese shipping company revealed that during the development process, there were various design challenges in using ammonia as fuel, in particular, those related to safety as ammonia is highly toxic. As disclosed, the developers managed to overcome these challenges without changing the size of the conventional tugboat and received Approval in Principle (AiP) from Nippon Kaiji Kyokai (ClassNK) in July 2022.