ArticleSeptember 20256 min read

What if nuclear power became the engine of world trade?

Published in Marine & Océans

Study Centre ILEB

Summary

With shipping accounting for nearly 3% of global greenhouse gas emissions, the article examines civil nuclear propulsion as a way to decarbonise world trade.

Article translated from French. The translation may contain inaccuracies: only the original version is authoritative. Read the original version

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Shipping is today the backbone of globalisation: around 80% of goods travel by sea. This omnipresence has a high ecological cost: the merchant fleet accounts for nearly 3% of global greenhouse gas emissions, as much as Germany. The International Maritime Organization (IMO) has set itself the ambitious goal of halving these emissions by 2050. Hull optimisation, port electrification and the emergence of alternative fuels such as LNG have made notable progress possible, but other, more radical solutions will be needed to reach carbon neutrality.

Now imagine carrying goods to the four corners of the globe without emitting a single gram of CO₂. Until now mainly confined to the military vessels (submarines and aircraft carriers) of a handful of nations, atomic energy is now bursting into the debate on the shipping of the future. This is the bet of SMRs (Small Modular Reactors), small modular nuclear reactors under development whose miniaturisation is finally opening the door to civil maritime propulsion. The promise is simple: a 400-metre container ship powered by a truck-sized reactor, with no fossil fuel. In concrete terms, this means zero CO₂ emissions and zero sulphur discharge. Icing on the cake: thanks to uranium’s exceptional energy density, the ship’s autonomy would be several years, freeing shipowners from the extra costs linked to oil price fluctuations and allowing continuous navigation, with almost no port calls dedicated to refuelling.

REACTORS AT THE HELM

Several concepts are being studied for naval propulsion: pressurised water reactors (PWR), molten salt reactors (MSR), lead-, sodium- or thorium-based reactors, each with specific features intended to enhance safety. Molten salt SMRs have the particularity of offering remarkable passive safety: in the event of an accident, the liquid fuel freezes below its melting temperature, trapping fission products and stopping the reaction. These intrinsic characteristics (no traditional control rods, high-temperature operation without risk of runaway) make the MSR a promising concept for maritime propulsion.

Beyond propulsion alone, these compact reactors open up new possibilities. On board, an SMR could supply the electricity needed to run the ship, or even power port terminals during calls (berthing without drawing on the local grid). Some projects even envisage producing green hydrogen or carbon-free ammonia on floating platforms linked to the reactor, to fuel lighter vessels (other than container ships).

A RACE THAT HAS ALREADY BEGUN…

Today, only one cargo ship, the Russian Sevmorput, commissioned in 1988, is nuclear-powered. However, all over the world, alliances are being forged between nuclear and shipping players. In Asia, the South Korean conglomerate HD Hyundai has presented a concept for a 15,000 TEU container ship powered by an onboard SMR, while in China the Jiangnan shipyard is working on a 24,000 TEU thorium-powered nuclear cargo ship. In Europe, Italy’s Fincantieri is collaborating with the start-up Newcleo (a TechnicAtome spin-off) and the RINA organisation on civil applications, and Norway is studying the regulatory feasibility of nuclear merchant ships. The major shipowners (CMA CGM, Maersk, MSC, etc.) are following these developments closely.

Across the Atlantic, major initiatives are emerging. Under the impetus of TerraPower (Bill Gates’s group) and Core Power (United Kingdom), a consortium bringing together the Southern Company (USA) and Orano International (France) has launched the Maritime-MSR project. It aims to equip the world’s 17,000 or so largest cargo ships with nuclear propulsion using onboard MCFRs (Molten Chloride Fast Reactors). In total, some 318 GW of capacity would thus be spread across small reactors of 15 to 50 MW each. For lighter vessels, the programme plans to produce synthetic fuels on board (green hydrogen and ammonia) using the reactors’ surplus energy, allowing smaller ships to use more traditional engines without CO2 emissions.

FRENCH EXPERTISE

France, with its unique experience in onboard nuclear power (submarines, aircraft carriers), has every asset to play a leading role in this revolution. It is already running ambitious programmes: the EDF–CEA–TechnicAtome–Naval Group consortium is developing the Nuward project, a 170 MWe PWR SMR designed to be deployed on land or, in a more compact version, on board a ship.

On the industrial front, the French ecosystem is ready. Naval Group has the expertise to integrate a reactor into a civil hull (drawing on its experience with ballistic-missile submarines, attack submarines and the aircraft carrier Charles de Gaulle), while the shipyards of Saint-Nazaire and Cherbourg master the construction of large ocean-going hulls. Framatome, TechnicAtome and Orano in parallel contribute their know-how on fuel, enrichment and safety. This value chain – from naval design to reactor integration – is operational and constitutes a strategic advantage for France.

COSTS STILL HIGH, BUT ROOM FOR PROGRESS

The main obstacle today is cost. The initial investment to equip a cargo ship with an SMR remains much higher than for a conventional fuel oil or LNG vessel. The construction of the modular reactor alone can account for most of the price of a traditional container ship. Added to this are specific operating costs: specialised crew training (adapted STCW modules), increased maintenance by nuclear technicians, enhanced insurance and more complex safety and port-call procedures (radiological checks, etc.). However, these extra costs must be weighed against potential long-term savings. On the one hand, fuel costs would be almost nil: only a few tens of kilograms of enriched uranium would be needed for years of navigation, a marginal cost compared with thousands of tonnes of fuel oil. On the other hand, logistics would be greatly simplified: no more need for multiple technical calls to refuel, which would reduce port fees and the risk of supply disruptions.

VOICES ARE BEING RAISED

As nuclear cargo ship projects multiply, a new ecosystem of actors is organising to support regulators. In April 2024, eleven major maritime and nuclear industry players – from HD Hyundai to Lloyd’s Register, from Bureau Veritas to TerraPower – founded the Nuclear Energy Maritime Organization (NEMO) in London. Its purpose: to offer a platform for dialogue between shipowners, builders, classification societies and international authorities in order to draw up clear standards for the deployment, operation and decommissioning of nuclear-powered ships. This new actor presents itself as a link between the International Maritime Organization, the IAEA and states, sharing expertise and good practice to establish the highest safety standards.

These efforts tackle a legal vacuum inherited from the 1960s-1980s, when attempts to build nuclear cargo ships came up against ports’ refusal to receive them and the absence of an insurance framework. NEMO’s founders say they want to anticipate these obstacles by working on port-call protocols, liability regimes and public acceptability. The first positive signals exist. In September 2025, Samsung Heavy Industries and the Korea Atomic Energy Research Institute obtained the first international certification (Approval in Principle) for an LNG carrier powered by a molten salt nuclear reactor, issued by the American Bureau of Shipping and the Liberian Registry.

A NEW ERA FOR SHIPPING?

Given the limits of alternative fuels and the climate emergency, nuclear propulsion no longer appears as a technical utopia, but as a serious path for France and its European partners to reinvent global shipping. In this transition, confidence in French industry is fully justified: from Naval Group to TechnicAtome, from Framatome to the CEA, France already has a complete ecosystem capable of designing, deploying and securing this type of technology at naval scale. It is now up to the state to invest massively in this emerging sector, as it did for aviation and space, so as to make it an industrial, ecological and strategic driving force. For the two great technological challenges of the 21st century are now clearly identified: the transport and storage of goods and of data. Mastering one of them, or better still both, will determine a country’s ability to weigh in the economic and political dialogues to come. Maritime nuclear power could thus become one of the most powerful levers for projecting France and Europe into tomorrow’s decarbonised economy.

Note on the author

Lorenzo Specty, aged 22, holds degrees in political science and history and is trained in communication and institutional relations. After studying at the Sorbonne, he co-founded Deep Blue, a university think tank that brings together students from the major Parisian grandes écoles and universities around maritime issues. He recently joined the editorial team of Marine & Océans.