Nuclear vessel 'could be floating charging station for electric cruise ships'

The 149-metre-long vessel features helicopter pads, firefighting equipment, rescue booms, workboats, autonomous surface vehicles and airborne drones, cranes, laboratories and a lecture lounge.

Molten salt reactors (MSRs) use fuel dissolved in a molten fluoride or chloride salt, which functions as both the fuel (producing the heat) and the coolant (transporting the heat away, and ultimately to the electricity generating equipment). There are a number of different MSR design concepts, and a number of interesting challenges in the commercialisation of many, especially with thorium (to breed fissile uranium-233).

To demonstrate the feasibility of Thor, Ulstein has also developed the Sif concept, a 100-metre-long, zero-emission expedition cruise ship. Accommodating up to 80 passengers and 80 crew, Sif will offer silent, zero-emission expedition cruises to remote areas, including Arctic and Antarctic waters. The vessel will run on next-generation batteries, utilising Thor to recharge while at sea.

Ulstein said Thor's charging capacity has been scaled to satisfy the power needs of four expedition cruise ships simultaneously. Thor itself would never need to refuel. As such, Thor is intended to provide a blueprint for entirely self-sufficient vessels of the future.

"Here we have two concepts in one to showcase a cleaner, safer and more sustainable way ahead for cruise ship owners and operators, not to mention maritime in general," said Ulstein Chief Designer Øyvind Kamsvåg. "Thor and Sif demonstrate what is possible when we approach challenges from a new direction."

The company claims the Thor concept is "capable of making the vision of zero-emission cruise operations a reality" and may be "the missing piece of the zero-emissions puzzle for a broad range of maritime and ocean industry applications."

"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 CEO Cathrine Kristiseter Marti. "We believe Thor might be the answer we've been looking for. Thor is essentially a floating, multi-purpose 'power station' that will enable a new battery revolution.

“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 ban the environmental impact of cruising. Thor enables replenishment of energy and supplies on site, while also boasting the technology to facilitate rescue operations, as well as conducting research tasks. It is, in effect, a crucial piece of infrastructure to support sustainable and safer operations."

Lars Ståle Skoge, Commercial Director at Ulstein Design & Solutions AS, added: "We have huge confidence in this solution and want to engage further in conversations about how we can enable the necessary changes the world demands."

In November 2020, a multinational team including Core Power (UK) Ltd, Southern Company, TerraPower and Orano USA applied to take part in cost-share risk reduction awards under the US Department of Energy's Advanced Reactor Demonstration Programme to build a proof-of-concept for a medium-scale commercial-grade marine reactor based on MSR technology.

Earth 300, in March 2021, launched the concept for a 300-metre-long, MSR-powered research ship equipped with 22 cutting-edge laboratories with 160 of the world's leading scientists, working in collaboration to bring rapid, far-reaching solutions to market.

The United Nations International Maritime Organisation has mandated that shipping must reduce emissions by 50% of the 2008 total, before 2050.