The Norwegian shipbuilding company Ulstein has developed a design concept for a cruise ship fueled by a molten salt nuclear reactor. In the company’s concept, the 500-foot-long, 60-passenger ship, named Thor—in reference to the Norse god as well as the thorium used in the reactor core–would generate its electricity with the onboard reactor. The ship would also serve as a charging station for a fully electric companion ship named Sif, named after the goddess who was Thor’s wife.
Overcoming stigma: Ulstein’s chief designer, Oyvind Gjerde Kamsvag, explains that the company has long been interested in nuclear power but has been concerned about the stigma associated with this energy source. The company is now exploring MSR technology because it operates at a much lower pressure than other nuclear reactors and cannot suffer a meltdown.
MSRs are under development in several countries, and commercialization is still a ways away. However, Ulstein thinks that “we could launch a fully operational [nuclear-powered] ship within 10 to 15 years,” according to Gjerde Kamsvag.
Greener cruises: In Ulstein’s two-ship concept, the Sif companion ship would have high-capacity, fire-resistant solid-state batteries to store electricity obtained from the reactor on Thor. These are the kinds of batteries that engineers are developing for use in electric cars, but their widespread adoption could be a decade away.
The nuclear- and battery-powered ships are being designed in preparation for the world’s need to cut greenhouse gas emissions. Ecotourism is on the docket, as well. For example, in 2026, the West Norwegian Fjords are to be closed to all ships that are not zero-emission vessels. Ulstein is preparing for the possibility that similar regulations will be imposed on other waterways around the world.
In addition to cruise ships, the company believes that MSRs would be viable electricity sources for other kinds of ships, including power barges, which could carry electricity to crucial sites such as disaster areas and developing countries.