Helion Energy

APrivateFounded 2013🇺🇸Everett, Washington

CEO

David Kirtley

Data verified as of Jul 21, 2026

Summary

Helion Energy is building fusion generators aimed at producing commercial electricity from fusion. Its Polaris prototype began operating in late 2024 and in February 2026 became the first privately developed fusion machine to demonstrate measurable deuterium-tritium fusion at 150 million degrees Celsius. Helion is now advancing Orion in Malaga, Washington, where site work began in 2025 for the company's first commercial machine intended to deliver electricity from fusion to Microsoft, while a smaller new 'Tiny Merge' testbed is being built to iterate on plasma formation faster. On June 4, 2026 Helion closed a $465M Series G led by Thrive Capital at a $15.5B post-money valuation, lifting total funding to roughly $1.5B; OpenAI is in advanced talks to buy fusion power from Helion at gigawatt scale, prompting Sam Altman to step down as board chair to recuse himself from those negotiations.

Company OverviewRead the long-form profile of Helion Energy

Main Products

Polaris

Operational

7th-generation fusion prototype designed to demonstrate electricity production from fusion using Helion's pulsed magneto-inertial architecture and direct electricity recapture.

Operating in Everett, WA, since late 2024. Achieved 150 million degrees C and first private D-T fusion in February 2026, and Helion is now working to ramp repetition rate from one pulse every ~10 minutes toward 1 Hz operation and demonstrate electricity production.

Plasma Temperature150 million °C

Pulse Rate TargetFrom ~1 pulse/10 min toward 1 Hz

FuelD-D, D-T, D-He-3

Bank Energy50 MJ+

Tiny Merge

Under Construction

Smaller, agile FRC fusion testbed roughly one-eighth the size of Polaris (~8 feet long) used to iterate on plasma formation and ring-merging experiments far faster than the larger machines. Helion sees Tiny Merge as a key learning loop to de-risk Orion ahead of the 2028 Microsoft delivery deadline.

Helion says Tiny Merge is being built at its Everett campus and is targeted to come online by the end of summer 2026 so the team has roughly two years to feed its findings into final Orion designs.

Size vs Polaris~1/8 (≈8 ft long)

PurposeAgile FRC formation & merging testbed

Target OnlineEnd of summer 2026

Orion

Under Construction

First commercial fusion power plant, designed to generate 50+ MWe. Located in Malaga, Chelan County, Washington, on land leased from Chelan County PUD near Rock Island Dam. Power will be marketed by Constellation Energy to Microsoft data centers.

Site work began in July 2025, and by October 2025 Helion had cleared the approval pathway for all major structures including the fusion generator building. In June 2026 Helion secured Radioactive Materials and Air Emissions licenses from Washington State — the world's first regulatory licenses for a fusion power plant — clearing it to proceed with the generator building. Helion remains focused on delivering power for Microsoft by 2028 with ramp-up thereafter.

Target Output50+ MWe

LocationMalaga, Chelan County, Washington

CustomerMicrosoft (via Constellation Energy)

What's Next

Bring Tiny Merge online and use it to inform Orion

Stand up the Tiny Merge agile testbed by the end of summer 2026 and use its faster experimental loop to lock in final FRC formation and ring-merging choices that flow into the Orion power plant design.

Late 2026

Raise Polaris repetition rate toward 1 Hz

Push Polaris from one pulse every ~10 minutes toward sustained 1 Hz operation — the rate Helion needs to convert fusion energy into recapturable electricity in commercial operation.

2026–2027

Orion plant completion

Complete construction of the Orion fusion power plant in Malaga, Washington, and begin commissioning. With the assembly and office structures finished and Washington State's world-first fusion Radioactive Materials and Air Emissions licenses secured in June 2026, work now moves to the fusion generator building. This will be the world's first commercial fusion facility.

2028

Deliver 50+ MWe to Microsoft

Fulfill the world's first fusion power purchase agreement by delivering 50+ MWe of electricity to Microsoft data centers via Constellation Energy, with financial penalties on Helion if the 2028 deadline slips.

2028

Finalise the OpenAI gigawatt-scale supply deal

Move the OpenAI negotiations from term sheet to a binding agreement — reportedly 5 GW by 2030 scaling to 50 GW by 2035 — and identify the sites and Orion-class plants needed to deliver that capacity. Talks remained ongoing and unsigned as of mid-June 2026.

2026–2027

Advance the Nucor deployment

Move the Nucor commercial agreement from customer commitment into a concrete plant deployment for a 500 MWe fusion facility serving industrial manufacturing, with operations targeted as soon as 2030.

2030s

Recent News

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Jul 18

Fusion industry hits record $4.48B in annual funding

The Fusion Industry Association's 2026 report, released July 13, said 56 fusion companies raised a record $4.48 billion in the year to mid-2026 — up 69% from 2025 — lifting cumulative private fusion investment to $14.24 billion and industry employment above 16,000. The largest rounds came from Commonwealth Fusion Systems ($863 million) and Helion Energy ($465 million), and 71% of surveyed companies still expect a fusion plant to deliver commercial electricity in the 2030s. The tally underscores accelerating investor conviction as demand for clean, firm power for AI data centers grows.

Commonwealth Fusion Systems

Jun 20

Helion wins world's first licenses for a fusion power plant

Helion Energy said on June 16 it has become the first company in the world to secure the regulatory licenses required to build and operate a fusion power plant, after the Washington State Department of Health issued it a Radioactive Materials License and a Radioactive Air Emissions License. The licenses cover Orion, Helion's roughly 50-MW fusion plant under construction in Malaga, Washington, and clear the company to proceed with its generator building now that assembly and office structures are complete. Fusion is regulated under a byproduct-material framework rather than as a fission reactor, and the milestone advances Helion's pledge to deliver fusion power to Microsoft by 2028.

Jun 17

Helion raises $465M Series G at $15.5B valuation

Fusion developer Helion Energy closed a $465 million Series G round in early June, lifting the Everett, Washington company's valuation to about $15.5 billion. The round was led by Thrive Capital, with new backers including Lux Capital, Peak XV Partners and Ford Motor executive chairman Bill Ford, and will fund Helion's first power plant, expand Washington manufacturing, and support its pledge to deliver fusion power to Microsoft by 2028. The raise follows Helion becoming the first company in the world to secure regulatory licenses for a fusion power facility and reporting measurable deuterium-tritium fusion at 150 million degrees Celsius on its Polaris prototype.

Jun 5

Helion raises $465M Series G at $15.5B fusion valuation

Helion Energy on June 4 closed a $465 million Series G led by Thrive Capital at a $15.5 billion post-money valuation, lifting total funding to roughly $1.5 billion as the Everett, Washington startup races to deliver fusion electricity to Microsoft from its Orion plant in Malaga by 2028. New investors include Lux Capital, Peak XV Partners, Alta Park Capital, Anti Fund, BoxGroup and Ford Motor Executive Chairman Bill Ford, joining existing backers SoftBank Vision Fund 2, Lightspeed, Mithril, Capricorn and Good Ventures; the cash will scale manufacturing and feed the Polaris prototype and forthcoming Tiny Merge testbed campaigns.

Operations & Revenue

StatusPre-revenue

Development stage — Orion site work is underway in Malaga, Washington, but Helion has not yet delivered commercial electricity. With Orion's assembly and office buildings complete, construction has moved to the fusion generator building following Washington State's June 2026 world-first fusion plant licenses. Polaris is operating in Everett and the company is standing up the smaller Tiny Merge testbed (targeted online by end of summer 2026) to iterate faster on plasma formation. First revenue still depends on Orion supplying Microsoft on Helion's 2028 contractual deadline, with a much larger gigawatt-scale supply deal still under negotiation with OpenAI for 2030 and beyond as of early July 2026.

Pipeline & Contracts

Microsoft Power Purchase Agreement

World's first fusion PPA — 50+ MWe of electricity to be delivered via Constellation Energy to Microsoft data centers by 2028. The contract carries financial penalties on Helion if it misses the 2028 deadline.

Nucor Power Plant Agreement

Customer agreement to develop a 500 MWe fusion power plant at a Nucor steel manufacturing facility in the United States by 2030; the deal also included Nucor's investment in Helion.

OpenAI Fusion Supply Talks

OpenAI is in advanced negotiations to buy fusion electricity from Helion at gigawatt scale — reportedly 5 GW by 2030 and up to 50 GW by 2035, equivalent to ~12.5% of Helion's planned production. No site has been selected yet and the agreement is not finalised.

Helium-3 production

Fusion byproduct valuable for medical imaging, quantum computing, and other applications.

Key Metrics

Employees

~500

Est. Annual Revenue

Pre-revenue

Total Funding

~$1.5B invested (incl. June 2026 Series G)

Plasma Temperature

150 million °C (13 keV) — standing private-fusion record; ~200M °C targeted for a commercial plant

Commercial Commitments

50+ MWe for Microsoft; 500 MWe planned with Nucor; OpenAI 5 GW (2030) / 50 GW (2035) under negotiation

Valuation

$15.5B post-money (June 2026 Series G)

Timeline

2026First private D-T fusion

Polaris achieves 150 million degrees Celsius and becomes the first private fusion machine to demonstrate deuterium-tritium fusion.

2026OpenAI fusion power talks; Altman steps down as board chair

Reports surface that OpenAI is in advanced talks with Helion to buy 5 GW of fusion power by 2030, scaling to 50 GW by 2035 — roughly 12.5% of Helion's planned production. Sam Altman, who is Helion's largest individual investor, steps down as board chair and recuses himself from the negotiations to manage the conflict of interest.

2026Tiny Merge agile fusion testbed under construction

Helion confirms it is building 'Tiny Merge', an ~8-foot, roughly one-eighth-scale FRC testbed designed to iterate on plasma formation and merging far faster than the full Polaris prototype, with the goal of de-risking Orion ahead of the 2028 Microsoft delivery commitment.

2026$465M Series G at $15.5B valuation

Helion closes a $465M Series G on June 4, 2026 led by Thrive Capital at a $15.5B post-money valuation, with new investors Lux Capital, Peak XV Partners, Alta Park Capital, Anti Fund, BoxGroup and Bill Ford joining existing backers SoftBank Vision Fund 2, Lightspeed, Mithril, Capricorn and Good Ventures. Total funding to date crosses ~$1.5B, with proceeds earmarked for scaling manufacturing and accelerating Polaris and Tiny Merge ahead of the 2028 Microsoft commitment.

2026World's first fusion power plant licenses

Washington State's Department of Health issues Helion a Radioactive Materials License and a Radioactive Air Emissions License for Orion on June 16, 2026, making Helion the first company in the world to secure the regulatory licenses required to build and operate a fusion power plant. Granted under the byproduct-material framework that regulates fusion separately from fission reactors, the licenses confirm Helion's facilities, trained personnel and safety programs and clear it to proceed with Orion's fusion generator building now that assembly and office structures are complete.

2025Orion plant groundbreaking

Breaks ground on Orion, the world's first commercial fusion power plant, in Malaga, Chelan County, Washington.

2025Orion permitting milestone

Chelan County grants a Conditional Use Permit that clears the approval pathway for all major Orion structures, including the fusion generator facility.

2023Microsoft PPA signed

Signs the world's first fusion power purchase agreement with Microsoft for 50+ MWe of electricity by 2028.

2021Trenta reaches 100M degrees

6th prototype Trenta reached 100 million degrees Celsius after a 16-month, 10,000+ pulse test campaign.

2021$500M Series E

Raises $500M Series E led by Sam Altman, with up to $1.7B in milestone-based commitments — the largest private fusion round at the time.

2015Energy recovery milestone

Demonstrated 95%+ round-trip magnetic energy recovery over 1 million pulses — critical for commercial viability.

2014Y Combinator

Accepted into Y Combinator. Won 2013 National Cleantech Open Energy Generation competition.

2013Founded

Helion Energy founded by David Kirtley, John Slough, Chris Pihl, and George Votroubek to commercialize magneto-inertial fusion.

Funding

Cumulative disclosed raise · dated rounds

Round	Date	Amount	Investors
DOE/NASA grants	2011	$5M	U.S. Department of Energy, NASA
Seed / Series A	2014	$1.5M	Y Combinator, Mithril Capital
Series D	2020	$40M	Dustin Moskovitz (Good Ventures)
Series E	2021	$500M (+$1.7B milestone commitments)	Sam Altman (lead), Mithril Capital, Capricorn Investment Group
Series F	2025	$425M	Lightspeed Venture Partners, SoftBank Vision Fund 2, Sam Altman, Mithril, Nucor
Series G	2026-06-04	$465M ($15.5B post-money)	Thrive Capital (lead), Lux Capital, Peak XV Partners, Alta Park Capital, Anti Fund, BoxGroup, Bill Ford, SoftBank Vision Fund 2, Lightspeed, Mithril, Capricorn, Good Ventures