ClassNK Greenlights Mitsubishi’s Ammonia Fuel Supply System

Mitsubishi Shipbuilding, part of Mitsubishi Heavy Industries (MHI) Group, has acquired an approval in principle (AiP) from the Japanese classification society ClassNK for its ammonia fuel supply system (AFSS).

The AiP has been issued for the AFSS developed for the X-DF-A, a large, low-speed two-stroke ammonia-fueled engine under development by WinGD, a Swiss designer and licensor of large marine engines.

In June 2023 Mitsubishi Shipbuilding and WinGD concluded a memorandum of understanding (MoU) to undertake joint technical studies on an AFSS, aiming to contribute to the achievement of a new target set by the International Maritime Organization (IMO) of net zero greenhouse gas (GHG) emissions in the global maritime industry by or around 2050.

In February 2024, the joint studies resulted in finalization of the basic design for an AFSS for the X-DF-A engine under development by WinGD.

The AiP was acquired together with approval of a new ammonia gas abatement system (AGAS), and now technical studies will go forward with WinGD toward commercialization, Mitsubishi said.

As ammonia emits no CO2 when combusted, it is attracting attention today as a fuel with the potential to contribute significantly to reducing GHG emissions in the maritime industry, and is expected to be utilized in the future as a source of stable, clean energy.

Going forward, Mitsubishi Shipbuilding will continue to develop marine ammonia handling systems, including fuel supply systems for ammonia combustion systems for the X-DF-A and other engines, as well as various ammonia gas abatement system systems.

Mitsubishi Shipbuilding will further promote decarbonization of the maritime industry by proposing the design and engineering of ammonia-fueled ships and onboard plants - comprising multiple ammonia-fueled combustion systems such as main engines, power generation engines, and boilers, the company added.