German startup Proxima Fusion claims it has made a “breakthrough” in nuclear fusion, unveiling what it says is the world’s first blueprint for a commercial power plant.
The startup’s claim is the latest development in the race to create working nuclear fusion plants, which researchers believe could provide hugely efficient energy for the planet.
Recent advances in AI have led to rapid increases in the speed of simulation technology, allowing researchers at Proxima to test and improve designs faster than previously possible, says Proxima cofounder Francesco Sciortino.
But building reactors capable of generating more energy than they consume remains a key challenge.
Proxima’s power plant design, which it developed in partnership with the Max Planck Institute for Plasma Physics (IPP) in Germany, marks the first time anyone has shown how all the constituent parts of a commercial fusion reactor could work together, says Sciortino.
“No-one has ever created a coherent concept for a commercial power plant,” says Sciortino. “This is a moment in which everyone in the fusion community will have to acknowledge things have changed.”
Fusion breakthroughs
Nuclear fusion is the process of combining hydrogen atoms to release energy, recreating a similar process that occurs in the sun’s core.
Fusion promises some big advantages compared to fission — the process nuclear plants currently use, which involves splitting atoms — including an almost unlimited fuel source in hydrogen, lack of greenhouse gas as a byproduct and a lower chance of meltdowns.
But fusing atoms comes with huge engineering challenges, including heating hydrogen isotopes to more than 100m degrees celsius and safely containing the plasma that forms as a result.
While governments in Europe have invested billions of euros into fusion research, fusion startups across the Atlantic have raised 75% of the total private capital invested into the sector, according to a 2024 report from the Fusion Industry Association.
Some of the biggest raises in the sector include Pacific Fusion’s $900m in October and Commonwealth Fusion Systems’ $1.8bn in 2021.
By comparison, the best funded fusion startups in Europe include UK-based Tokamak Energy, which has raised $335m — including $275m from private investors and $60m from the UK and US governments — and Germany’s Marvel Fusion, which has picked up $110m.
Proxima has raised €65m, including €30m from VCs and €35m in public funding. The startup is one of 60 companies globally working on fusion technology, according to Dealroom, using a number of different approaches.
First commercial fusion power plant blueprint
Founded in 2023, Proxima is a spinout from the IPP and is focusing on building a commercial fusion reactor using a device called a stellarator, which contains the superheated plasma in a twisted doughnut shape, using magnetic fields. The complex geometry of the doughnut is what keeps the plasma in place.
The devices developed from tokamaks, another approach to fusion which uses magnets to contain plasma in a more simple doughnut shape, with the addition of an electrical current to keep it confined.
The lack of a current in a stellarator means reactors would be inherently more stable, says Sciortino. But until a recent set of breakthroughs, stellarator technology was just “hypothetical”.
New generations of superconducting magnets and the world’s most powerful demonstrator stellarator, the Wendelstein 7-X in Germany, meeting theorised performance predictions in 2022, however, have propelled the technology to being a serious candidate for developing fusion.
Recent AI-driven breakthroughs in simulation technology (which allow researchers to test ideas virtually) have also helped increase the speed of development of Proxima’s stellarator designs, says Sciortino.
“Analysing new potential designs for component parts of stellarators used to take weeks, now we do it in 20 minutes.”
While there have been designs for demonstrator fusion power plants developed in the past, Proxima has developed the first blueprints for a commercial one, Sciortino tells Sifted.
This is partly due to the startup’s stellarator approach, which while harder to initially design due to its complex shape doesn’t have the problem of instability associated with tokamaks, he says.
Proxima’s concept makes use of only currently available materials, which the startup says means it could be built using today’s supply chains. It also “balances physics performance and engineering constraints for power production for the first time,” Sciortino adds.
Race for nuclear fusion
There’s still a long way to go to developing a working fusion reactor.
While Proxima hopes to build its commercial reactor by the late 2030s, it’s a very optimistic bet that fusion will be powering the grid anytime soon.
It’s not realistic to expect that to happen before the 2050s, says Thomas Klinger, director at IPP — due to the engineering challenges of building the myriad of constituent parts of a reactor, many of which are still in development.
That’s a risk for Proxima, which is effectively banking on work-in-progress tech, like the high temperature superconducting magnets needed to confine the super-heated plasma, being built in time, he tells Sifted.
Commercially it’s also not clear how expensive it would be to build a nuclear fusion reactor from scratch (Klinger estimates between €5-10bn) and generating return on investment for backers hinges on how effective the plant is if and when it’s up and running, he says.
“It’s important to acknowledge we’ve still got to go and build a fusion reactor,” says Sciortino. “The race isn’t to make a design of a plant — the race is to make the power plant itself.”
Going forward, Proxima will be investing in designing specialist magnets — which it’s hoping to have developed by 2027. If it manages it, it would be an “inflection point” in fusion, Sciortino tells Sifted.
To get there, the startup is hoping to raise a funding round that would top the €65m it has picked up so far by the end of the year.
Further down the line, if it stays the path of building a commercial fusion reactor, Proxima will need billions of euros more. Raising that depends on convincing investors to cough up cash on a scale Europe’s fusion startups have never seen before.
Read the orginal article: https://sifted.eu/articles/fusion-breakthrough-proxima-news/
