Nuclear-powered LNG carrier design receives initial approval

Scope for SMR propulsion in maritime

Nuclear power could potentially power zero-emissions ships and be used to produce e-fuels, and SHI rival South Korean shipyard group Korea Shipbuilding & Offshore Engineering also has its sights set on developing SMRs for use on commercial newbuilds. It struck a deal in February 2024 to do just that with technology providers TerraPower -- founded by Bill Gates in 2008 -- and Core Power using SMRs based on TerraPower’s molten chloride fast reactor design.

China, too, has been active in developing maritime applications for SMRs. At the Marintec China maritime exhibition in Shanghai in December 2023, China State Shipbuilding Corp’s Jiangnan Shipyards unveiled a molten-salt nuclear reactor-driven 24,000-TEU box ship design.
And a nuclear-powered concept that garnered industry attention in 2022 from Ulstein Group was featured during a presentation at a Riviera Maritime Media conference in early 2023 by chief designer Øyvind Gjerde Kamsvåg. 

In late April 2022, Ulstein published a concept design for a vessel powered by a thorium molten salt reactor (MSR) that could, in theory, enable zero-emissions cruise operations by operating as a mobile power charging station for battery-driven cruise ships.

Named Ulstein Thor, the 149-m 3R (replenishment, research and rescue) design’s MSR would generate excess electricity. This would allow the vessel to operate as a mobile power charging station for battery-driven cruise ships.

To demonstrate its feasibility, Ulstein developed the Ulstein Sif concept, a 100-m, 160-person, 80-passenger capacity, zero-emissions expedition cruise ship. The Ice Class 1C vessel is designed with a future generation of batteries that would allow for longer operation times, and the vessel would use Thor’s excess MSR energy to recharge while at sea.

Ulstein believes the concept design may represent a missing piece in the zero-emissions puzzle for a broad range of maritime and ocean industry applications, but that it "comes down to scaleability, size and capacity".

In terms of the timeline, Mr Kamsvåg said the company believes the technology could be available in five years and implemented in 10 years. 

"But it’s all about incentives," he said.

"We expect flag states will be the pioneers. We see there are a lot of possibilities and obstacles. If there’s enough motivation, if the incentives are there, it can happen," he said.

And in July 2025, proponents of nuclear power for the commercial maritime sector, NEMO, were granted consultative status with the International Atomic Energy Agency and International Maritime Organization (IMO). One of the goals of NEMO is to work with IMO to establish a set of standards for using nuclear power on board commercial vessels. Additionally, the London-based NGO wants to work with IMO and the International Atomic Energy Agency to develop standards for floating nuclear power plants that can operate offshore or in coastal areas. Recent efforts have been aimed at potentially using modular reactors to decarbonise oil and gas production.

Among those joining NEMO is US-based SMR company TerraPower, nuclear reactor power plant company Westinghouse EC and Danish MSR company Seaborg.

Riviera’s LNG Shipping & Terminals Conference will be held in London on 21-22 October 2025. Use this link to register your interest and attend the event.