Nuclear propulsion is back on the table for maritime decarbonisation, and this time, the industry isn’t just kicking the tires—it’s considering a full test drive. DNV’s latest white paper, Maritime nuclear propulsion: Technologies, commercial viability, and regulatory challenges for nuclear-powered vessels, doesn’t just revisit the idea; it frames it as a viable, if complex, solution to shipping’s emissions crisis. The catch? The industry has to move fast, collaborate globally, and tackle some serious hurdles—technological, regulatory, and commercial—to make it work.
The stakes are high. Shipping burns 350 million tonnes of fossil fuel annually, accounting for about 3% of global carbon emissions. The IMO’s 2050 net-zero target has set the stage for a scramble toward decarbonisation, and nuclear is suddenly looking less like a sci-fi fantasy and more like a practical option. “Nuclear propulsion, once regarded as a distant prospect, is now under active consideration as a real option for the commercial maritime fleet,” says DNV Senior Principal Researcher Ole Christen Reistad. Shipyards and owners are weighing the promise of near-zero-emission power against the reality of introducing a transformative—and highly regulated—technology into global fleets.
But here’s the rub: maritime nuclear isn’t just land-based nuclear in a different outfit. It’s a beast of its own, with unique challenges. Mobility, exposure to harsh sea conditions, and operational demands mean reactors for ships can’t just be repurposed from power plants. DNV’s paper highlights the need for a tailored fuel cycle, from production to disposal, and a regulatory framework that’s both predictable and internationally accepted. The IMO and the International Atomic Energy Agency (IAEA) will need to step up, setting standards for fuel management, ship construction, and operational protocols. Classification societies like DNV will play a critical role in standardising safety and compliance across borders.
The white paper also underscores the need for compelling business models. Nuclear propulsion won’t fly if it’s not cost-competitive. DNV’s case studies suggest that reactors costing below USD18,000/kW could be competitive by 2050, even without full decarbonisation. Modular, standardised designs could streamline construction, simplify maintenance, and ease regulatory approvals—key factors in making nuclear viable for commercial fleets.
But the real kicker? Public acceptance. Nuclear energy still carries baggage, and the maritime industry will need to address safety, security, and waste management head-on. DNV’s paper emphasises that advances in automation, digitalisation, and modular design will be critical in winning over stakeholders and ensuring safe, secure operations.
The timing of DNV’s white paper is no coincidence. Just as it was released, South Korea’s HD KSOE secured an Approval in Principle (AiP) from DNV for a 15,000 TEU-class container vessel powered by small modular reactor (SMR) technology. This isn’t just a concept—it’s a concrete step toward making nuclear propulsion a reality. The design incorporates a supercritical CO2-based power generation system, promising higher thermal efficiency and a smaller footprint than conventional steam-based systems.
HD KSOE’s Chief Technology Officer Chang Kwangpil calls the design a “key milestone” in decarbonising shipping. The vessel includes a novel shielding and containment system to ensure reactor safety even in extreme scenarios like collisions or sinkings. DNV’s Technical Director Geir Dugstad echoes the significance, noting that the AiP represents an important first step in verifying nuclear-powered vessel designs.
The collaboration between DNV and HD KSOE highlights a broader trend: the maritime industry is serious about exploring nuclear. But the road ahead isn’t just about technology—it’s about coordination. Governments, regulators, shipowners, and technology providers must work together to build a viable, safe, and accepted path forward.
The question now isn’t whether nuclear propulsion can work—it’s whether the industry can move fast enough to make it happen. With the IMO’s 2050 deadline looming, the clock is ticking.