Magnets That Attract Profits: Fusion’s Quiet Powerhouse Takes Center Stage
As fusion energy nears viability, breakthroughs—and bottlenecks—in superconducting magnets are shaping its future
In the race to commercial fusion energy, the spotlight often falls on plasmas and reactors. But behind the high temperatures and advanced physics lies a quieter, more stubborn challenge: the magnets. Specifically, high-temperature superconducting (HTS) magnets are complex, costly, and crucial to success.
“It’s not trivial,” said Antonio Pellecchia, Sales Manager at ASG Superconductors, an Italian firm with over 75 years of magnet manufacturing experience. “A defect can lead the magnet to malfunction. So you've got to design it in a way that it is working like the most damaged part of the HTS conductor.”
Pellecchia explained that the quality of superconducting tape is never uniform, and designing magnets means designing around their weakest points. "You must downgrade the performance to make sure your magnets live."
This reality starkly contrasts the promise of HTS: a material that can carry immense electric current with zero resistance, enabling the powerful magnetic fields fusion reactors need. However, those same superconductors are fragile and difficult to manufacture at an industrial scale.
“HTS is a promising material,” said Itxaso Ariza, Chief Technology Officer at Tokamak Energy, a UK-based company developing spherical tokamak fusion systems. “But you have to acknowledge that there are some defects in the tape, plan for that, and improve the magnet performance by creating alternative paths for the current.”
She added that her team at Tokamak Energy has spent over a decade improving the magnets themselves and adapting their designs to accommodate real-world material limitations.
“We’re able to cope with small defects, defects that perhaps in other HTS magnets, and certainly in LTS [low-temperature superconducting] magnets would have led to the magnets to fail.”
Ariza noted that their approach allows for more compact, modular magnets, which is an advantage when scaling to commercial systems.
“We’ve drilled holes in magnets and found that there was no problem with the magnet function,” she said.
The ability to manage imperfections in the tape without compromising performance gives Tokamak Energy confidence in applying its HTS technology beyond fusion, including in aerospace and maglev transport.
“When we talk to anybody in aerospace or magnetic levitation trains and they look at what we’ve done, they think the HTS time is now.”
Engineering Complexity Meets Market Demand
This shift in focus—from fusion reactors to the magnet technologies behind them—was the central theme at Fusion Fest 2025, an event hosted by The Economist in London.
The panel, titled Pulling in profits: magnets and other fusion spin-offs, brought together scientists, startup executives, and investors to explore how fusion’s enabling technologies could generate near-term value in non-fusion markets.
Francesco Volpe, founder and CEO of Renaissance Fusion, a French startup working on stellarator-based fusion, took a different approach to magnet construction.
“For us, it started as a necessity to become a developer and producer of HTS tapes, not just of HTS magnets,” he said.
Renaissance Fusion doesn’t wind traditional coils. Instead, they coat large cylindrical surfaces with HTS materials and engrave electrical circuits into them using lasers. “Effectively, instead of making three-dimensional sculptures, we are making two-dimensional engravings. We are painting on an HTS canvas with a laser brush.”
This technique, he explained, also offers a solution to the problem of defects.
“In narrow tapes, you can have these defects clogging the current… whereas if you have very wide HTS, as we need to, you get the bonus that now you have sparse defects here and there, but the current just slaloms through them.”
Volpe sees significant potential for these engraved superconductors in non-fusion fields like medical imaging, energy storage, and electric vehicles.
“The requirements of fusion are not unique to fusion,” he said. “Wherever you need a large magnet—meaning you need to magnetize a large volume with a strong magnetic field and high precision—you can use these technologies.”
Spin-Offs from Fusion Labs
In some cases, technologies developed for fusion have already matured into spin-off businesses. TAE Technologies, a California-based firm that has been working on field-reversed configuration fusion since 1998, has become a case study in this evolution.
“We didn’t plan it this way,” said Jonathan Toretta, TAE’s Chief Revenue Officer. “We’ve been at this since 1998. We built a huge IP stack. We got very good at doing things in-house… and part of that market came to us and said, ‘Can we sort of borrow this?’ And we said, ‘It’ll cost you.’ And so they’re paying us for that.”
TAE has spun off companies focused on power solutions and cancer treatment, including a boron neutron capture therapy venture. Toretta emphasized that these businesses, while separate in management and equity structure, still benefit the parent company. “They are spun all the way out… but we’ve wanted to retain, by way of returns to our shareholders, and by way of returns to the company, a hand on these businesses.”
This approach allows TAE to diversify its revenue without being distracted from fusion.
“I’ve had that conversation a couple of times today—whether or not a company focused on fusion is distracted by the fact that it’s got a life sciences business and a power solutions business,” he said. “I would say… they’re non-distracting.”
Still, Toretta acknowledged the steep difficulty of the work.
“It’s extremely hard. I’ve never had a job that’s been this difficult. I think anyone on our team would say the same thing.” He added that fusion startups often underestimate the scale of the challenge. “Our huge IP stack comes at the cost of trying to solve problems we did not think we could solve.”
Following the Money—and the Tape
Chris Good, Managing Partner at Pine Island New Energy Partners, a U.S. private equity firm focused on electrification supply chains, said his firm is closely watching HTS development for its near-term commercial potential.
“We’re looking for technologies which already have a working product… and a book of demand, and we’re looking to put capital into help them scale up.”
Good pointed out that most HTS tape today comes from countries like China and Russia, which presents geopolitical and supply chain risks.
“There’s a massive demand for Western countries to invest in this HTS tape supply,” he said. “Whether it’s within fusion or in transmission, it’s in data centers, whether it’s in magnets for the use within medical machines, this material will be essential for the future of the world economy.”
The technical challenges remain enormous. “The superconducting material is a micron thick, and it’s rare earth metals that have to be deposited in such a way that their crystalline nature means that they are superconductors,” Good said. “Getting that to work in a lab is hard. Getting that to scale up to thousands of kilometers of tape per year is a whole different level of difficulty.”
Still, the investment case is strong, particularly in adjacent markets with more apparent returns.
“We can make a good return by looking at the HTS tape that is being used for transmission,” he said. “That may be more straightforward and will be in greater demand in the short term.”
What Comes After Magnets?
While the magnet sector dominates many fusion discussions today, other enabling technologies—such as cryogenics, lasers, and even materials for radiation shielding—are also under development. Not all of them will have spin-off markets.
“Tritium handling, honestly, lithium blankets, etc.—it’s very hard for me to see what the applicability of those is,” Good noted. “Maybe there is. I don’t know what it is today.”
Still, Pellecchia and Volpe both emphasized that the broader superconducting ecosystem has a real chance to shape the near future of global energy. ASG is working on new applications of magnesium diboride cables, which Pellecchia says “could be used to power up a data center, or to connect an offshore wind field.”
Volpe even envisions future robots with soft, fluid movements driven by the liquid metal research developed for fusion. “One day, maybe we will have liquid metal-based robots,” he said.
Whether commercial fusion arrives within the next decade or not, the technologies created along the way—especially superconducting magnets—are already attracting investment, partnerships, and new opportunities.
For now, fusion remains a distant goal, but the innovations enabling it are quickly becoming valuable on their own.