Japan’s Big Three Shipowners Back Standard CO2 Carrier Design

Japan’s three largest shipowners—NYK Line, MOL, and K Line—along with leading shipbuilders Mitsubishi Shipbuilding and Nihon Shipyard, have secured Approval in Principle (AiP) from ClassNK for a standardised 42,000 cu m liquefied CO₂ carrier design. This development is part of Japan's broader strategy to support carbon capture and storage (CCS) projects and transportation infrastructure.

Collaboration and Design Process

The project involves six key partners: NYK, MOL, K Line, Nihon Shipyard, Mitsubishi Shipbuilding, and the joint venture MILES. The partners have been working under a Memorandum of Understanding (MoU) since December 2025 to develop standard designs for LCO₂ carriers and alternative-fuel ships. This collaboration aims to create a common vessel platform that can be built repeatedly at Japanese yards, reducing engineering workloads and improving construction efficiency.

Risk Assessment and Safety Policy

A comprehensive risk assessment (Hazard Identification Study "HAZID") was conducted for the 42,000 cu m low-pressure LCO₂ carrier design. The study drew on the extensive experience of the three largest Japanese shipping groups—NYK Line, MOL, and K Line—in low-pressure gas carrier operations to identify specific risks associated with CO₂ handling.

"The risk assessment has been crucial in establishing a robust safety policy that will be reflected in the design of these vessels," said a spokesperson from MILES Co., Ltd. The approval from ClassNK, which was presented at Gastech 2026 in Bangkok on September 15, marks the first concrete achievement through the MILES framework.

Market Demand and CCS Strategy

Japan anticipates a significant increase in demand for LCO₂ shipping as domestic CCS projects move towards commercial operation. Captured carbon dioxide needs to be transported from industrial centres to offshore or potentially overseas storage locations, which will drive the need for more dedicated carriers.

"The MOL Group has positioned environmental strategy as one of the core pillars of our management plan, ‘BLUE ACTION 2035.’ This project is a significant step towards achieving that vision," stated MOL's representative at the AiP ceremony. NYK Line and K Line also highlighted their commitment to CCS projects as part of broader sustainability initiatives.

Standardization Benefits

The standardisation effort aims to provide workload savings and greater efficiency in design and construction, enhancing Japan’s construction capabilities in the emerging CO₂ shipping market. This common design platform will enable yards to build LCO₂ carriers in larger numbers, potentially reducing costs and speeding up delivery times.

"The 42,000 cu m design is a significant step forward for the CCS sector," explained ClassNK representatives. "It not only addresses current needs but also sets a foundation for future growth as the industry matures."

What this means for operators

The standardisation of CO₂ carriers through this collaborative effort will benefit operators by providing a more predictable and efficient vessel design that can be built at multiple Japanese shipyards. This reduces dependency on bespoke builds, lowers risks associated with unique design work, and ensures consistency in operations across the CCS value chain.

"For our clients, having a standardised design framework means we can offer more reliable vessels for CO₂ shipping," said a NYK Line executive. "This will be particularly beneficial as we scale up CCS projects nationwide."

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