Is nuclear energy shedding its unfairly earned reputation as a dirty, dangerous alt-fuel? Perhaps the maritime industry, mainstream media and public are still not completely sold on the concept –but, compared to when we covered the topic two years ago (see Ship & Boat International January/February 2022, pages 28-30), attitudes appear to be softening.
The cost-of-living crisis and the energy price hikes of 2022 may have helped to drive this mind shift. Public anger over inflated gas and electric bills, accompanied by a round of protests across cities in the UK and Europe (including the memorable sight of Italian citizens burning their energy bills in the street) has led some to reconsider nuclear power as a cheap, sustainable energy source – not to mention a safe one, if handled correctly. And, in most cases, nuclear power is handled correctly and in accordance with long-established regulations, as the previous article highlighted.
Nuclear energy is no longer limited to warships and subs, though. Ulstein has unveiled its THOR concept, a 149m, Thorium-powered vessel equipped with a molten salt reactor, that could be utilised to recharge the batteries aboard passing ferries, cruise ships and research vessels. Norway’s Institute for Energy Technology has also undertaken a project to develop a 70m, nuclear-powered shrimp trawler, utilising a small modular reactor, or SMR. These initiatives have been supported by the Nuclear Energy Maritime Organization (NEMO), which has attracted IACS-affiliated class societies to its ranks.
Tom Walters, partner at law firm HFW, comments: “We’ve seen technology move at quite a pace, from high-pressure water reactors using Uranium to different isotopes in more stable conditions and in different configurations. As is always the case, technology is leading the law, and the law’s having to run to catch up.
“The technology for the third or fourth generation of reactors is already there. The next generation of SMRs, whether based on molten salt or some other form, are coming on very, very quickly.”
Superyachts: the ideal sector?
Until relatively recently, even enthusiastic advocates of nuclear energy as a maritime fuel conceded that it may take decades to appease the regulators and insurers and to win the public’s trust. The consensus was also that SMRs would predominantly fuel larger ships, leaving smaller yachts, fast ferries and workboats out of the loop. However, Walters and HFW associate Johanna Ohlman view smaller nuclear boats as being entirely feasible, and have identified the superyacht sector as a possible forerunner of SMR adoption.
Why yachts? As reported in previous issues of Ship & Boat International, the superyacht segment is keen to ‘green up’ its image, having come under fire from environmental activists (and from a few supply chain insiders) for its carbon-intensive activities. Like the nuclear industry, the superyacht sector has frequently been scapegoated and targeted despite its best efforts, with much of the criticism ignoring the fact that a new generation of affluent, younger yacht owners are moving away from the fume-belching builds of old.
Tom Walters, HFW: “It’s as much about having the newest technology…it’s almost kudos to say, ‘I’ve got a nuclear-powered yacht, what have you got?’”
Walters adds: “For superyacht owners, it’s as much about having the newest technology aboard one of their yachts; it’s almost kudos to say, ‘I’ve got a nuclear-powered yacht, what have you got?’ A lot of yacht owners are very aware of their environmental footprint. I think one of the first commercial maritime adopters is going to be somebody in the superyacht industry who’s got relatively deep pockets, and who thinks ‘I’m prepared to foot the bill for this’.”
Walters cites billionaire philanthropist Bill Gates – who has allegedly commissioned the world’s first hydrogen-powered superyacht, Project 821 – as an example of one high-worth individual pushing for SMRs, through his Terrapower business. Walters continues: “Another example is Lürssen Yachts, which has been working with Rolls-Royce to develop methanol propulsion for large yachts: methanol could be the stepping stone between where we are now, energy-wise, and a future power source.”
Lease model
The next question is: how would nuclear-powered superyachts work in practice? Even for well-heeled yacht owners, the Capex involved in installing a SMR is exorbitant. Walters and Ohlman suggest that leasing the reactor, instead of buying it, may be the most cost-effective means of installing it on board.
“If you could modularise the reactors so that they’re all a standard size, you could basically ‘plug in and play’,” says Walters. “Essentially, the reactor is just a steam generator; you have cold water in and steam out, and then a control system – that’s all you need.” The whole package could be scaled to fit inside a 20’ container and stored below the superyacht’s deck – though, Walters points out, “in due course, smaller versions may well be developed”.
“You’d own the yacht but lease the powerplant,” Walters continues, “and you’d have a dedicated reactor technician on board, trained by the reactor manufacturer. He or she would stay on board and integrate with the yacht’s crew, but be solely responsible for the reactor while the crew do everything else they need to do.”
If future reactors are developed to a standard size, they can easily be replaced. “The yacht can pull into a dry dock to commission a new reactor, pull out the existing one and slide in the new reactor,” Walters says. “By leasing the reactor, you remove that huge investment cost at the beginning of the project and you substitute what the owner would usually pay for fuel with a fixed sum payable over the yacht’s lifetime. In theory, the reactor’s fuelling cycle can be up to 15-20 years, so you may only need to refuel it once.” At the end of the yacht’s life, the reactor would be removed and recycled according to the country’s regulations.
Johanna Ohlman, HFW: “Nuclear-powered yachts would be able to sail into remote locations in need of renewable energy and there connect to the grid to supply electricity to the port”
“Five to six years”
Nuclear power could massively benefit yacht owners and designers in various ways. “The weight of an SMR will be much less than that of a diesel engine,” says Walters, “and, if you build at the same size as a conventional superyacht, there’s a huge amount of extra space to play with – or the owner could opt for a smaller yacht as a large engine room wouldn’t be required.”
Then there are the benefits of the nuclear yacht’s capability to generate surplus power, which can be put back into the grid. “The owner can generate power for the kiosks, shops and port/marina infrastructure,” says Walters. “These reactors don’t run cold: they tend to run at between 280-850° C, so there’s a source of heat there as well. Most of that heat gets used to turn water into steam, then steam drives the turbines and the turbines turn that into electricity, to power electric motors and propulsion.”
Ohlman adds: “Going back to the philanthropic mindset, nuclear-powered yachts would also be able to sail into remote locations, such as small island communities, in need of renewable energy, and there connect to the grid to supply electricity to the port.”
As to when we may see the first nuclear superyacht, Walters and Ohlman predict that it could take “five to six years, if not a decade” – an optimistic estimation, albeit one supported by the current rate of progress in SMR design. “If the technology moves at the pace it’s moving at now, and the law can change to accommodate it, there’s no reason why it couldn’t happen sooner,” Walters adds.
For the full in-depth article, see Ship & Boat International September/October 2024
