Japanese shipping major NYK and its partners say they have completed the world's first ship-to-ship ammonia bunkering operation involving an ammonia-fuelled vessel. The transfer took place on September 17 at Japan Marine United's Ariake Shipyard, with ammonia moved from the carrier Shoei Maru to a new medium gas carrier due for delivery in November. The vessel will now run sea trials using ammonia as fuel. The demonstration is part of Japan's Green Innovation Fund, a 2 trillion yen ($13.7bn) programme backing technologies for 2050 carbon neutrality. Ammonia is seen as a leading zero-carbon fuel for shipping because it emits no CO2 when burned, but its toxicity has made bunkering and onboard handling a major adoption hurdle. The partners developed dedicated operating procedures and used the exercise to collect practical data on moving ammonia safely between vessels. NYK already operates Sakigake, a tug converted in 2024 into what the company calls the world's first commercial ammonia-fuelled vessel, which has refuelled via truck-to-ship bunkering. This new ship-to-ship test moves the industry one step closer to normalising ammonia as a marine fuel, though commercial scale and clean ammonia supply remain open questions.
