Mitsui O.S.K. Lines, Ltd. (MOL), TSUNEISHI SHIPBUILDING Co., Ltd., and Mitsui E&S Shipbuilding Co., Ltd have received an approval in principle for an ammonia-fuelled gas carrier design from ClassNK.

The design is intended to achieve net zero CO2 emissions while underway. The design includes a MITSUI-MAN B&W type S60 two-stroke dual-fuel ammonia engine as the main mover. The engine itself remains under development.  

Ammonia is expected to be used as a ship fuel for decarbonisation since it does not emit CO2 when combusted. Meanwhile, adequate safety measures are imperative as it has been pointed out that ammonia is toxic to humans and corrosive to materials. ClassNK has been involved in projects aiming for zero-emission ships using ammonia fuel in terms of safety assessment, and has issued its “Guidelines for Ships Using Alternative Fuels” as a necessary standard to minimize the risks related to ammonia fuelled ships for the ships, crews, and environment by stipulating requirements for installation, controls, and safety devices.