“We are making nuclear power a cheap, sustainable and safe technology that can compete with fossil fuels and revolutionize energy markets,” says Seaborg Technologies on its website. A Copenhagen-based company that has received at least ten million euros of investment to start producing its floating nuclear plants.
Molten salt reactors were created in the 1950s as a safe alternative to water reactors. The Danish company has updated this technology and does not use normal salt, but a fluorine salt that is in solid state until they reach 500 ° C and then it melts allowing uranium to dissolve in it.
This is key to the security of this system, affirms the company. The reactor operates at a pressure close to atmospheric, when the fluorine salt is liquid it flows inside the reactor, mixing with the uranium and causing it to cool. If the fuel is exposed to the air, instead of a huge explosion of radioactive vapor as in traditional nuclear reactors, the salt solidifies with the nuclear fuel inside and forms a rock.
“We are not going to reduce the probability of an accident to zero, there will be accidents”, he comments Troels Schönefeldt, the CEO of Seaborg Technologies, in an interview with the Radio Spectrum podcast. “What we do, instead of reducing the probability, is reducing the consequences […] The consequence is that this fluorine salt will flow out of the reactor and explode outside the reactor. If you bomb it, it will explode and stay there. It will solidify and then you should no longer enter the area. You should actually keep 3 or 4 meters away until you can go there with a Geiger counter and clean it. ”
By becoming solid and not vapor, there is not so much danger of radiation spreading. The fluoride salt stone, in addition does not dissolve well in water, so if it fell into the sea, the settlement would continue without spreading further.
Seaborg Technologies CEO explaining his new technology
This reactor also has another security system that is activated if the temperature starts to rise uncontrollably. There is a plug of salt at the bottom that immediately melts causing the reactor core to empty and the contents to fall into a series of cooled drain tanks located below. This system, the company says, prevents uranium from being used to make nuclear weapons, is small enough to fit in a shipping container, and can operate for 12 years without having to change fuel.
Furthermore, according to Schönefeldt, his system could work with radioactive waste from other reactors And it could be a solution for managing this troublesome waste material. “It’s something to worry about for hundreds of thousands or millions of years, which is very troublesome. So it would be very attractive to reduce it to something that needs to be stored for a few hundred years, ”says Schönefeldt. And that’s what we can do. But being able to do something technically is not the same as being authorized to do it. So the problem, I would say, is mainly a regulatory problem. ”
A nuclear reactor on a barge
Another striking aspect of this system is that it is designed to go inside a barge. Seaborg Technologies offers several sizes that they can go from 200 MWe, which can generate the smallest to 800 MWe of the largest.
Schönefeldt afirma que the flexibility of movement offered by putting your jets on a ship is very important to the company. On the one hand, there is the saving of not having to buy land to build nuclear plants and, on the other, that they can be located anywhere on the planet that has access to the sea or a navigable river. In addition, it can be very easily connected to the electrical network so that energy is immediately available anywhere.
Schönefeldt says that it is very easy to mass-produce these types of boats without losing quality. In fact, it is so easy that the company ensures that It only takes 3 years from receiving an order until the reactor is ready to connect to the grid. For this they are going to make use of the Korean shipyards, thus taking advantage of their supply chains and their enormous production capacity. “If they want us to build not one reactor to start with, but a thousand, we could start by building a thousand,” says Schönefeldt. “That would take about three or four years in these yards. So there is basically no ceiling on how fast you can scale.”
Schönefeldt thinks that with this deployment can reach 95% of the world’s population, and especially to island regions such as Southeast Asia, from where they received their first order. “There are almost a billion people in Southeast Asia and the energy they will need from coal and gas is comparable to what is released in the world today. So even if we manage to decarbonize the other half of the planet, they will produce the same amount of electricity if there are no other alternatives, “he says.
When will they come into operation
The next steps for the company will be to have the prototype ready for operation in Southeast Asia in 2025, obtain regulatory approval of its design by 2026, and start serial production from 2027. But to achieve that, they will first have to overcome a series of obstacles.
The first is the technology itself. Salt is a corrosive material This affects the durability of the reactor on the inside, and as these ships are designed for at sea it will also wear out on the outside. The CTO of the company Eirik Eide Pettersen affirms that: “The core of Seaborg’s intellectual property is based on controlling corrosion in moderating salt, and applying lessons learned since the 1950s.”
Then there are the technical problems of starting any new technology. “It is not just a question of corrosion, but also how easy it is to assemble these things. Practical experience is important. They have to be welded, tested, inspected and maintained. We are working to have maybe 20 or 30 test loops in Copenhagen, with the experiments designed, assembled and executed, “says Pettersen.
But, the great obstacle to the implementation of this system is regulatory. Regulation on nuclear matters is very strict, but Schönefeldt believes that the fact that they are floating nuclear plants operating at sea opens the door to a new regulatory scenario. Also fundamentally based on safety, but adapted to new nuclear technologies rather than based on existing ones.
Finally is the battle against public opinion. Since the Chernobyl and Fukushima disasters the popularity of this type of power source has plummeted. Although the new nuclear plants that are being proposed have very little to do in terms of safety with those, This energy source is considered to be one of the least dangerous.
According to a compilation of studies by ourworldindata.com, nuclear energy causes 99.7% fewer deaths than coal, 99.6% less than oil and 97.5% less than gas. And it is only behind other renewables such as wind, solar and hydroelectric energy. It is also one of those that emit the least CO2, even below renewables such as hydropower.