The world’s first commercial-use ammonia-fuelled tugboat, Sakigake, has completed a successful three-month demonstration voyage in Tokyo Bay, achieving greenhouse gas (GHG) emission reductions of up to 95%.
The tug was developed by Nippon Yusen Kabushiki Kaisha (NYK) and IHI Power Systems, in collaboration with Nippon Kaiji Kyokai (ClassNK), under Japan’s Green Innovation Fund Project.
The project aims to accelerate the maritime sector’s transition to net zero. Development of the vessel began in October 2021 and was completed in August 2024.
Since then, it has been operated in Tokyo Bay, where its performance as a working tugboat was closely monitored.
Analysis of the vessel’s ammonia co-firing and GHG reduction rates consistently exceeded 90%, reaching around 95% across all main engine load ranges.
This marks the world’s first confirmed operational trial using ammonia as fuel in real-world tugboat conditions.
To celebrate this major milestone, a commemorative ceremony was held at the Port of Yokohama.
The Sakigake will continue operating in Tokyo Bay while further insights into ammonia-fuelled vessel performance are gathered.
Meanwhile, NYK, IPS and their partners are developing an ammonia-fuelled gas carrier scheduled for delivery in 2026, continuing efforts to decarbonise the global shipping industry.
