13 Jul 2022

ClassNK has issued an Approval in Principle (AiP) for an ammonia-fuelled tugboat (A-Tug) jointly developed by Nippon Yusen Kabushiki Kaisha (NYK Line) and IHI Power Systems Co., Ltd.

Ammonia is expected to be used as 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.

Ammonia-fuelled ships

ClassNK has been involved in projects aiming for zero-emission ships using ammonia fuel

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 minimise the risks related to ammonia-fuelled ships for the ships, crews, and environment by stipulating requirements for installation, controls, and safety devices.

ClassNK just carried out a design review of the A-Tug under R&D by NYK Line and IHI Power Systems in accordance with Part C-1 of its guidelines and issued the AiP on verifying that it complies with the prescribed requirements. That is the world's first AiP for a tugboat using ammonia as fuel issued by society.

For the two companies’ goal to realise the demonstration operation at the port of Yokohama in fiscal 2024, ClassNK will continue to support as the certification body and will strive to provide appropriate standards for ammonia-fuelled ships through the expertise gained from the collaboration.