Gyrotrons for Type One, PPPL's INFUSE trio and a Thea coil test at MIT

Kyoto Fusioneering will build the 170 GHz gyrotrons for Infinity One, Type One Energy's stellarator prototype in Tennessee, with deliveries scheduled to be completed in 2029. In the same four days, November 2 to 5, 2026, DOE's INFUSE program paired the Princeton Plasma Physics Laboratory with Helion, Kyoto Fusioneering and Thea Energy on three projects, and Thea announced a full-force coil test at MIT. Each is about who builds, tests or studies a piece of a fusion machine, not the machine itself.

Kyoto Fusioneering will build the gyrotrons for Type One's Infinity One

Kyoto Fusioneering will design, manufacture and factory-test 170 GHz, 1 MW-class gyrotron systems for Infinity One, Type One Energy's stellarator engineering prototype at the Tennessee Valley Authority's Bull Run site, the Japanese company announced on November 5, 2026. Gyrotrons make the high-power microwaves for Infinity One's electron cyclotron heating (ECH) system. They will be built and tested at Kyoto Fusioneering's Shiga Innovation Factory in Japan, and the company will supervise installation and site acceptance testing in Tennessee.

On a stellarator, that heating system can carry the whole load. Per the release, stellarators do not need plasma rotation for stability or confinement, so fusion ignition can be reached with ECH as the only heating method.

Deliveries are scheduled to be completed in 2029, the year Type One's January 2026 licensing release gave for Infinity One's commissioning and startup. The announcement does not say how many gyrotrons are on order or what they cost. Type One's chief technology officer, Thomas Sunn Pedersen, explained the purchase: "Our strategy is to partner with qualified, established manufacturers wherever feasible." That is the integrator pitch Type One made with its $200 million Series B in October.

Type One is not the only stellarator developer talking gyrotrons with Kyoto Fusioneering. Kyoto Fusioneering's October 28 memorandum with German stellarator developer Proxima Fusion also covers gyrotrons, as The Duck Curve reported, and the company says it is expanding its gyrotron production capacity "so that the supply base is in place before fusion power plants need it."

PPPL's three INFUSE projects pair it with Helion, Kyoto Fusioneering and Thea

Three of the 28 projects in DOE's fiscal 2026 INFUSE round pair the Princeton Plasma Physics Laboratory with a fusion company, according to the program's award records, posted November 2, 2026. INFUSE pairs private fusion companies with national laboratories and universities, with budgets of $100,000 to $500,000 per project; The Duck Curve covered the full round when DOE announced it the same day. PPPL's three:

• Helion Energy: Helion and PPPL's Hantao Ji will analyze reconnection experiments at the lab's FLARE facility, scaled to be relevant to the merging of field-reversed configuration plasmas, the approach Helion uses, to develop and validate models of micro-instabilities that may cause anomalous transport of energy and particles. The record is candid about the starting point: "The fusion performance demonstrated in Trenta still needs improvement for Helion's fusion technology to be a viable source of clean energy for the grid." Trenta was Helion's sixth prototype.
• Kyoto Fusioneering: Kyoto Fusioneering America and PPPL's Andrei Khodak will develop and validate modelling workflows for liquid-metal breeding blankets, covering how magnetic forces distort liquid-metal flow, heat transfer and drainage.
• Thea Energy: Thea and PPPL's Shurik Yatom will fire short laser pulses at boron targets in deuterium gas and measure the plumes with high-resolution spectroscopy, to characterize the boron vapor shields meant to protect the plasma-facing components of stellarator power plants.

The Thea project sends the company back to where it started: Thea says it spun out of Princeton University and PPPL in 2022. Thea holds three of the round's 28 projects, as our reading of DOE's selection list found; the boron study is one of them. The company says it is supported by nine DOE INFUSE awards and an ARPA-E SCALEUP award.

Thea Energy will test a full-force encircling coil at MIT

Thea Energy will test an encircling magnet for Eos, its planned integrated stellarator, at full magnetic field and full force at MIT's Plasma Science and Fusion Center (PSFC), the Kearny, New Jersey company announced on November 4, 2026. The PSFC brings cryogenic test facilities and expertise in high-temperature superconducting magnets. Beyond the full-force test, the two will analyze the coil's efficiency under power-plant-relevant conditions to build predictive models and test the magnet's resilience.

Eos uses 12 encircling coils and approximately 300 programmable shaping magnets. The shaping magnets are already built and validated for Eos at scale, by Thea's account; the MIT test is of an encircling coil. Zachary Hartwig, head of the PSFC Engineering Group, said: "Thea Energy is advancing a promising approach for fusion power plants, and PSFC's testing infrastructure is ideally suited to evaluate Thea Energy's encircling coils."

Thea is not the only stellarator developer leaning on MIT. Type One's magnet program builds on MIT's VIPER high-temperature superconducting cable technology, as our Series B coverage noted. Thea says the work aims to accelerate the de-risking of key milestones on its path to commercial fusion by 2035.