Yokohama purchases world’s first certified “environmental value” generated by ammonia-fueled tugboat

The City of Yokohama is strengthening its leadership in sustainable maritime innovation through an initiative supporting the ammonia-fueled tugboat Sakigake and accelerating efforts to promote next-generation marine fuels and reduce greenhouse gas emissions by purchasing “environmental value” generated from the vessel’s operation.

Sakigake, developed by a consortium including Nippon Yusen (NYK) and operated by Shin-Nippon Kaiyosha, is recognized as the first of its kind commercial-use ammonia-fueled vessel. Ammonia fuel emits no CO2 during combustion, making it a promising solution for decarbonizing the shipping industry.

A key achievement of this initiative is the world’s first third-party certification of reduced greenhouse gas emissions through actual vessel operations at the Port of Yokohama. These reductions were converted into what the project calls “environmental value,” which Yokohama purchased to promote broader understanding and adoption of ammonia fuel.

This initiative builds on years of collaboration between the city and private-sector partners. Key milestones include a 2022 agreement on accepting ammonia-fueled vessels, the world’s first truck-to-ship ammonia bunkering in 2024, and the accumulation of certified “environmental value” in 2025.

Through these efforts, Yokohama aims to visualize decarbonization challenges in ports and maritime industries while supporting local companies engaged in advanced environmental initiatives. The initiative also contributes to Yokohama’s broader goal of developing a Carbon Neutral Port (CNP) by 2050.