Commonwealth Fusion Systems relies on magnets for short-term revenue

Commonwealth Fusion Systems announced Thursday that it will sell its high-temperature superconducting magnets to Realta Fusion. This is the second in a series of deals, suggesting the company will rely heavily on its magnet technology to deliver much-needed revenue in the coming years.

“This is the largest transaction of its kind for CFS to date,” Rick Needham, the company’s chief commercial officer, told reporters on a conference call.

Commonwealth Fusion Systems (CFS) previously sold magnets to the University of Wisconsin’s WHAM experiment, with which fusion startup Realta works closely. The physics behind WHAM underpins Rialta’s approach to fusion power generation, known as a magnetic mirror reactor.

Inside the magnetic mirror, the plasma is trapped in a shape similar to two 2-liter soda bottles connected at the bottom. At each end, powerful magnets punch out the plasma and push it back toward the center. A weak magnet surrounds the center of the bottle shape.

To create a more powerful reactor, the Khosla-backed Realta only needs to expand the central section. And because their magnets aren’t as strong, they’re cheaper. As Rialta’s reactors grow in size, the cost per kilowatt-hour should fall.

CFS is pursuing another form of magnetic confinement fusion called a tokamak. In a tokamak, a D-shaped magnet casts a powerful field that keeps the plasma circulating inside in a donut shape. For years, the company has been refining its magnets with the goal of putting electrons from the Ark, a future commercial-scale nuclear reactor to be built in Virginia, onto the grid.

Both CFS and Realta owe their existence to the magnet itself. CFS was founded in 2018 after MIT scientists realized that a new class of commercially available high-temperature superconductors could support viable tokamak designs. Rialta was founded a few years later when physicists at the University of Wisconsin “realized there was a new technology, a game changer that would allow us to go back to the old days.” [magnetic] We reflect and leverage the engineering advantages of this concept,” said Co-founder and CEO Kieran Furlong.

In addition to the Realta and WHAM agreement, CFS is licensing high-temperature superconducting magnet technology to Type One Fusion, which is working on a third type of reactor design known as a stellarator. The latter deal doesn’t include CFS building the actual magnets for the company, but Christine Dunn, CFS’s head of external communications, told TechCrunch that could happen at some point.

The transaction will help CFS recoup its investment in magnet manufacturing. The startup spent seven years and hundreds of millions of dollars building a factory capable of manufacturing high-temperature superconducting magnets designed to specifications for fusion power generation. So far, that money has gone towards building the company’s demonstration reactor Sparc, which is not expected to be operational until later this year.

“Sparc is now 70% complete and the timing was perfect to begin supporting Realta with magnet manufacturing,” Needham said.

Because Realta and Type One pursue different reactor designs, CFS does not appear to consider them direct competitors at this time. In the market, the gap between Realta and CFS is even wider, with the former initially focused on industrial applications that require large amounts of heat.

To date, CFS has raised nearly $3 billion, a significant portion of all venture funding raised by fusion startups. This put the company in an enviable position, giving it the means to build major facilities such as magnet factories before its competitors. The startup pitches these deals as a service to the broader fusion industry, making available technology that would cost millions of dollars to replicate. That’s true, but it also gives you access to even more venture capital, even if it’s a long shot.

Updated at 1:45 PM ET: The CFS manufacturing facility makes HTS magnets, not tape, and will not be idle, but will be making additional magnets for Sparc. The article also incorrectly lists Rick Needham’s role as COO. He is the CCO.