Source: TechCrunch

Helion Reaches 150 Million °C in Polaris Prototype

The Everett, Washington‑based fusion energy startup Helion announced Friday that it has hit a key milestone in its quest for fusion power. Plasmas inside the company’s Polaris prototype reactor have reached 150 million °C, three‑quarters of the way toward what the company thinks it will need to operate a commercial fusion power plant.

“We’re obviously really excited to be able to get to this place,”
— David Kirtley, Helion co‑founder and CEO, told TechCrunch.

Polaris is also operating using deuterium‑tritium (D‑T) fuel—a mixture of two hydrogen isotopes—which Kirtley said makes Helion the first fusion company to do so.

“We were able to see the fusion power output increase dramatically as expected in the form of heat,” he added.

The startup is locked in a race with several other companies that are seeking to commercialize fusion power, a potentially unlimited source of clean energy.

Funding Landscape

• Inertia Enterprises announced a $450 million Series A round that included Bessemer and GV.
  TechCrunch article

• Type One Energy told TechCrunch it was in the midst of raising $250 million.
  TechCrunch article

• Last summer Commonwealth Fusion Systems raised $863 million from investors including Google and Nvidia.
  TechCrunch article

• Helion itself raised $425 million last year from a group that included Sam Altman, Mithril, Lightspeed, and SoftBank.
  TechCrunch article

While most other fusion startups are targeting the early 2030s to put electricity on the grid, Helion has a contract with Microsoft to sell electricity starting in 2028. That power will come from a larger commercial reactor called Orion, which the company is currently building, not from Polaris.

Reactor Designs: Helion vs. Competitors

How Helion’s Field‑Reversed Configuration Works

1. Fuel injection at the wide ends of the hourglass chamber creates plasma.
2. Magnets accelerate the two plasma streams toward each other.
3. The streams merge at 10–20 M°C.
4. Powerful magnets compress the merged “ball,” raising the temperature to 150 M°C in ** “It’s been a pleasant surprise that a lot of that technology has been easier to do than maybe we expected,” Kirtley said. “We’ve been able to produce helium‑3 at very high efficiencies in terms of both throughput and purity.”

Kirtley believes other companies may eventually adopt He³ fuel and is open to selling it:

“Other folks — as they come along and recognize that they want to do this approach of direct electricity recovery and see the efficiency gains from it — will want to be using helium‑3 fuel as well.”

Orion: The Commercial‑Scale Reactor

Alongside Polaris experiments, Helion is building Orion, a 50‑megawatt fusion reactor needed to fulfill its Microsoft contract.

“Our ultimate goal is not to build and deliver Polaris. That’s a step along the way towards scaled power plants,” Kirtley explained.

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Tim De Chant – Climate Reporter, TechCrunch

Tim De Chant is a climate reporter at TechCrunch. He has written for a wide range of publications, including:

• Wired magazine
• Chicago Tribune
• Ars Technica
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• NOVA Next – where he was the founding editor

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• Lecturer in MIT’s Graduate Program in Science Writing
• Knight Science Journalism Fellow (MIT, 2018) – studied climate technologies and explored new business models for journalism
• Ph.D. in Environmental Science, Policy, and Management, University of California, Berkeley
• B.A. in Environmental Studies, English, and Biology, St. Olaf College

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