Expert blog – October 2, 2023
Nuclear energy is often the subject of heated discussions. Some see it as an indispensable component in the energy transition, while others see too many objections. Jonathan Moed, nuclear energy expert at StartGreen, describes in this blog why he sees a future in the new generation of nuclear reactors.
Necessary baseline
A lot of solar and wind energy is currently being generated. This will only increase in the coming years. That is positive, but unfortunately, energy generation from sun and wind fluctuates significantly. The energy baseline we need is currently still generated by coal and gas-fired power plants to ensure there is always sufficient electricity. We want to move away from this due to the relatively high greenhouse gas emissions.
Securing the baseline
One could store energy from wind and sun in batteries. However, that would require an enormous amount of batteries. It remains to be seen whether there are sufficient (affordable) raw materials for this. As you may have read in Michiel’s blog, storing sustainably generated electricity in hydrogen is an alternative solution. Nuclear energy is another alternative that can provide a stable supply.
In my view, you have to do both: it is not one or the other. You must therefore invest in storage as well as build nuclear power plants for a stable baseline. However, the current generation of nuclear power plants cannot quickly scale energy production up and down (this is called ramping), as is possible with gas and coal-fired power plants. And that is not the only disadvantage of the current generation of reactors.
Third-generation reactors
The current, third-generation reactors (‘gen three’) in use today are so-called light-water reactors, also known as LWRs. This technology uses solid fuel (uranium and plutonium). The heat released by nuclear fission is converted into steam. The steam drives turbines, thereby generating electricity.
Disadvantages and risks of gen three
However, there are several disadvantages to LWRs. They produce radioactive waste when burning uranium, which requires long-term storage and management due to its long-lasting radioactivity. In addition, fuel efficiency is limited: LWRs can only extract a small portion of the energy from uranium before the fuel rods must be replaced. This results in a significant amount of used fuel waste. Furthermore, LWRs require large amounts of cooling water to function; water that is extracted from the natural environment.
Additionally, the risks of LWRs are significant. Although the uranium is low-enriched, it can still be used for the production of nuclear weapons. And then there is the risk of a nuclear meltdown (meltdown). If the cooling fails, the fuel rods overheat and melt through everything into the ground.
Chernobyl and Fukushima
In any discussion about nuclear energy, the names Chernobyl and Fukushima are quickly mentioned. Almost everyone knows the story of Chernobyl by now, partly due to the highly popular HBO miniseries Chernobyl from 2019. In Fukushima, on March 11, 2011, the three operational reactors at the plant were automatically shut down within seconds of the start of the earthquake. The subsequent tsunami damaged the emergency generator, preventing the reactor from being cooled. This led to a meltdown. No one died or (to date) became ill from the meltdown itself. However, the earthquake and tsunami claimed 18,000 victims.
Advantages of fourth-generation reactors
As we speak, hard work is being done on fourth-generation generators, which are based on a much safer technology. I particularly see a future in the molten salt reactor (abbreviated as MSR). In this technology, the fuel (thorium) floats in molten salt. Thorium is much less radioactive than uranium, it cannot be used to make weapons, and there is much more of it available.
Furthermore, the risk of a meltdown with molten salt is minimal. As mentioned, the thorium floats in molten salt. As soon as that salt becomes too hot, the so-called freeze plug melts, all the salt drains at once into a dump tank, and the nuclear reaction stops. An MSR reactor also produces much less long-lived nuclear waste: the waste from a gen-3 reactor is harmfully radioactive for 10,000 years, while that of an MSR is ‘only’ 300 years. That is still a long time, but not so long that no one in the future will know where it is stored.
Who has the best design?
Because molten salt reactors are smaller than light-water reactors, they can scale up and down quickly. If we invest in fourth-generation reactors now, they will be able to provide that aforementioned rampable baseload in the future. Several start-ups are working on this. Note: no party has yet built an MSR plant. They are all still working on paper. All calculations are based on simulations. The question then is: who has the design for something that actually works?
Solid and feasible
We have conducted extensive due diligence, and it shows that the design of the Amsterdam-based Thorizon is the most promising. Their design is solid and feasible, giving it a good chance of being realized. Furthermore, the thorium molten salt reactor developed by Thorizon uses long-lived nuclear waste as fuel in addition to thorium.
More investors
When I saw Thorizon’s design, I was immediately very enthusiastic. I spoke extensively with the founders of Thorizon. Ultimately, we decided with PDENH to invest 3 million euros in it and sought out other investors. The remainder of the necessary 12.5 million euros was invested by Positron Ventures, Invest-NL, Impuls Zeeland, Huisman Equipment, and several informal investors. Fortunately, more and more venture capital firms are investing in deep tech. I have no doubt that we will bring new investors on board over the next four years.
Read also: PDENH invests in reactor that converts nuclear waste into CO2-free energy
Female CEO
As with every investment we make, we are closely involved in Thorizon’s growth. We helped them complete the team. At the beginning of May, we found a new CEO: Kiki Lauwers. She has worked at commercial companies such as Bol.com and McKinsey and has a background in aerospace engineering. The fact that Thorizon’s new CEO is a woman aligns well with StartGreen’s impact objective to promote diversity.
No better alternative yet
If it becomes a success, theoretically 17 large MSR reactors with a capacity of 1000 MW could provide the entire Netherlands with electricity. Should we have started sooner? Yes, definitely. Experiments with molten salt were already being conducted in the 1960s. Now is the second best time to start. Perhaps in 15 years, there will be an even better alternative. But if you don’t invest in this now, there is also a chance that you won’t have a better alternative later. That is why we are investing in Thorizon.
