Norwegian designer Ulstein has unveiled a revolutionary blueprint for zero-emission cruising using nuclear power.

The yard group said the Ulstein Thor vessel will feature a thorium molten salt reactor (MSR) to generate “vast” amounts of clean, safe energy.

The 149-metre prototype is a first for shipping, but is not a cruise ship itself.

Thor is instead a replenishment, research and rescue vessel that will operate as a mobile power/charging station for a new breed of battery-driven passenger ships.

Ulstein believes the concept may be the missing piece of the zero-emissions puzzle for a broad range of maritime and ocean industry applications.

The company has also designed a 100-metre, 160-passenger and crew cruise vessel called Sif to go with the Thor unit.

“We have the goals, ambition and environmental imperative to switch to zero-emission operations, but, until now, we haven’t had the solution,” said Ulstein chief executive Cathrine Kristiseter Marti.

“We believe Thor might be the answer we’ve been looking for,” she added.

The CEO explained that expedition cruise ships operate in increasingly remote and environmentally fragile areas.

At the same time the industry faces growing pressure from diverse stakeholders to preserve nature as it is and remove the environmental impact of cruising, she said.

“Thor enables replenishment of energy and supplies on site, while also boasting the technology to facilitate rescue operations, as well as conducting research tasks,” Marti added.

“It is, in effect, a crucial piece of infrastructure to support sustainable and safer operations. Thor literally has the power to change our entire industry,” she said.

Thorium and salt

Thorium, an abundant, naturally occurring metal with low radioactivity, has been identified as having huge potential for clean power.

MSRs are a new technology that work by dissolving the thorium in liquid salt.

The ensuing chain reaction heats the salt, producing steam to drive a turbine and create electricity, with none of the dangers associated with traditional reactors.

Thor’s charging capacity has been scaled to satisfy the power needs of four expedition cruise ships simultaneously, but will never itself need to refuel.

UK start-up Core-Power is also working on MSR technology for cargo vessels, with backers like Singapore container line X-Press Feeders.

Jan Emblemsvag, a professor at the Norwegian University of Science and Technology, said MSRs have enormous potential for enabling clean shipping.

“There is so much uncertainty over future fuels, but here we have an abundant energy source that, with the right approach, can be safe, much more efficient, cheaper, with a smaller environmental footprint than any existing alternative,” he added.