Nuclear-Powered Offshore Vessels To Become A Reality Soon

The maritime industry is at a critical juncture, struggling to meet IMO’s decarbonisation goals for 2030 and 2050, as shipping is a major contributor to pollution and global warming. Shipowners and stakeholders are seeking a fuel that can keep engines running without breaking the bank. Though hydrogen, ammonia and methanol are being promoted as the answer, other studies are revealing better alternatives.

The “NuProShip II” project has brought a new perspective into the picture.

The study was led by Vard Design in cooperation with DNV, Emerald Nuclear, Vard Electro, Island Offshore, and the project leader, the Norwegian University of Science and Technology (NTNU).

The project shows how nuclear propulsion can improve efficiency, reliability, and environmental performance in the maritime industry.

VARD and its partners confirmed that nuclear-powered Dynamic Positioning (DP) vessels are achievable; they have envisaged a vessel class with an unlimited range, zero emission and a level of power density that batteries cannot match.

VARD has finalised a concept design for a nuclear-powered construction vessel based on an existing reference design.

This article talks about the breakthroughs of the project, the advantages of using nuclear power in the offshore sector and the regulatory issues surrounding the matter.

But first let us understand the energy profile of the offshore vessels, which, unlike container ships, which sail steadily from port A to B, operate in a high-energy statis, using Dynamic Positioning (DP) systems.

These are thrusters, controlled by advanced computer systems to fight powerful waves, wind, and currents to keep the ship stable when it is near a subsea target, a move which requires immense power.

A DP vessel could be idle for a minute and then need 90% load the next minute because of a sudden gust or shift in current.

Presently, this is achieved by using several diesel generators in parallel, making the process inefficient, leading to the generation of significant emissions and consuming a lot of fuel.

The NuProShip II study simply states that this is something a nuclear reactor could do. For an offshore operation in remote waters of the Barents Sea or off the Brazilian coast, doing away with the bunkering will not only save cost but also increase work efficiency.

Findings of NuProShip II (Nuclear Propulsion in Merchant Shipping) are different from the nuclear propulsion used in earlier military submarines or icebreakers.

The project, set to end this year, moved from conventional Pressurised Water Reactors (PWR) toward Generation IV Small Modular Reactors (SMRs).

The Helium Gas-Cooled Reactor

The VARD Study focuses on using a helium-gas cooled reactor, and not the water-cooled ones that function at high pressures to stop the water from boiling. On the other hand, gas-cooled reactors use inert helium gas as a coolant.

They use TRISO as fuel and are made with passive safety features, meaning that in case of a total shutdown, the reactor cools itself without the need for human intervention or the need for active pumping systems.

Additionally, helium enables the use of higher temperatures while the reactor is working, which means higher thermal efficiency.

Supercritical CO2 Turbines (sCO2)

The most unique thing about the NuProShip II design is the power conversion system, which uses Supercritical CO2 turbines.

Supercritical CO2 is between liquid and gas, and compared to steam turbines using steam, it is more energy dense, allowing power generation equipment to be smaller than a steam plant. This frees up a lot of space below deck for equipment, moonpools and living areas for crew members.

Thermal Batteries and Redundancy

A nuclear reactor runs at a steady pace and does not go high and then stop many times, a requirement for DP vessels, which need instant power hikes.

To solve this problem, the project brought forward thermal battery systems. The reactor charges the battery at a stable rate, and when the DP system needs a power surge, the energy is drawn from the thermal buffer, not by ramping the reactor up and down.

This means the vessel meets the DP2 and DP3 redundancy requirements, the industry standard for safety, where a single failure cannot result in a loss of position.

Credibility

The credibility of NuProShip II comes from those involved. VARD, a subsidiary of Fincantieri, has provided ship design, making sure the reactor can fit into hulls of present-day vessels, eliminating the need for redesign of basic vessel superstructure.

The involvement of DNV, a top classification society, assures regulators that the vessel is safe.

Emerald Nuclear has brought its nuclear domain expertise regarding the reactor core and fuel cycle to the innovation project.

The presence of Island Offshore signals market interest in the commercial adoption of the proposed design.

Regulatory Hurdles

The present regulatory framework for nuclear merchant vessels is nonexistent or outdated.

The International Maritime Organisation (IMO) has the Code of Safety for Nuclear Merchant Ships (Resolution A.491), but it was adopted in 1981 and focuses on old technology (like the NS Savannah or Otto Hahn).

It does not take into consideration modern passive-safety SMRs or gas-cooled designs.

Before steel is cut, some issues need to be addressed. Firstly, there is an urgent need for a new code which speaks about the inherent safety of Gen IV reactors.

Also, maritime authorities of all countries need to agree to allow these ships to enter their waters, a step requiring international treaties outlining liability, insurance, etc., beyond just P&I club coverage.

There is a lot of misunderstanding about the technology and new-generation nuclear reactors among the masses, which should be cleared so they are seen not as floating disasters but as safe, closed-loop systems.

Funding

The program is funded by the Research Council of Norway, reflecting the country’s push toward advanced and sustainable maritime technologies.

The conclusion of NuProShip II in 2026 is not the end, and work will shift to the SFI SAINT (Sustainable Applied and Industrialised Nuclear Technology) centre.

With NOK 96 million ($9.8 million) in public funding and NOK 200 million ($20.5 million) in industry contributions, SFI SAINT will run for eight years (2026–2034).

NuProShip II proved the concept, and now SFI SAINT has to industrialise it.

The Norwegian government will focus on the supply chains, training crew for these nuclear vessels and finalising their prototype design. If the timeline holds, the keel laying of the first nuclear offshore vessel could happen in the 2030s.

Conclusion

Combining helium gas-cooled reactors and sCO2 power cycles solves two biggest problems in offshore energy: emissions and endurance.

The question now shifts to “Will we?” The technology is ready to mature, but the regulatory bodies and public perception must move at the same speed as the engineering. If they do, the maritime industry may be on the verge of its most significant propulsion shift since the move from sail to steam.

You might also like to read-

• What are Offshore Vessels?
• What is a Dynamic Positioning Ship?
• 14 Types of Ships with Dynamic Positioning System
• Understanding Modern Dynamic Positioning Systems For Ships