ClassNK validates decarbonization potential of dual-fuel LPG/ammonia carrier newbuild

July 1, 2025, by Sara Kosmajac

The Japanese classification society ClassNK has examined the operational and environmental performance of a recently delivered dual-fuel liquefied petroleum gas (LPG)/ammonia carrier, seeking to confirm whether the unit can ‘successfully’ contribute to green transition efforts.

As disclosed, the society evaluated the newbuilding christened Crystal Odyssey under the “Zero-emission Accelerating Ship Finance” program, jointly operated by ClassNK and the Development Bank of Japan (DBJ), which provided financing to the unit’s owner, Kumiai Navigation.

Kumiai Navigation, which is a Singapore-based wholly owned subsidiary of Japanese shipowner Kumiai Senpaku, received the LPG/ammonia carrier in June 2025 from shipbuilder Sakaide Works of Kawasaki Heavy Industries (KHI).

According to ClassNK, under the program, the scoring model of which is based on the notions of “decarbonization, environmentally friendly performance, and innovativeness”, several factors were considered during the ship’s evaluation:

The use of LPG fuel is projected to slash carbon dioxide (CO2) emissions by around 15% compared to the use of conventional fuel oil;
The vessel is engineered and partially equipped to utilize ammonia as fuel in the future (ammonia-ready);
The fitting of an exhaust gas recirculation (EGR) system and a selective catalytic reduction (SCR) system enables the ship to stay in line with the International Maritime Organization’s (IMO) Tier III nitrogen oxide (NOx) stipulations;
The application of LPG fuel ensures compliance with the IMO’s sulfur oxide (SOx) regulations, especially the 0.1% limit in emission control areas (ECAs).

The 227-meter-long Crystal Odyssey is understood to have shown “excellent performance” during the examination.

Kumiai Navigation has long collaborated with Kawasaki Heavy Industries, having contracted the shipbuilder for multiple units beyond Crystal Odyssey, which was booked in February 2023. Less than a month following this order, for instance, Kumiai Navigation tapped KHI for yet another 86,700 cbm LPG/ammonia tanker.

At present, the Tokyo-based shipping player reportedly owns and operates twenty vessels, including bulk carriers, gas carriers, and others.

On the other hand, ClassNK recently issued another stamp of approval, this one to compatriot maritime transport company Mitsui O.S.K. Lines (MOL) and Mitsubishi Shipbuilding, a part of Mitsubishi Heavy Industries (MHI), for their jointly developed liquefied CO2 (LCO2)/methanol carrier.

With the AiP secured, the partners said they would move on to developing the carrier and achieving commercialization together with relevant companies in the supply chain.

View on Offshore-energy.