Building the world's first fusion power plant.
Public company, workplace, funding, and market signals
Updated Aug 2, 2026
Helion Energy is a privately held fusion-energy company founded in Washington State in 2013. It is developing pulsed, non-ignition fusion systems intended to generate clean, reliable electricity, with Orion under construction as its first commercial fusion power plant.
Primary product
Commercial pulsed fusion power systems: Polaris is the seventh prototype and Orion is the planned 50-MWe first commercial plant, intended initially to supply Microsoft.
Founded
2013
Headquarters
1415 75th St SW, Everett, Washington 98203, United States
Team size
Approximately 500–550 worldwide; third-party workforce estimate of 531 as of March 2026, while LinkedIn's company data has shown 368.
Work style
Onsite
Industry
Renewable energy power generation
Sub-industry
Fusion energy; magneto-inertial and pulsed plasma power generation
Offices
Business model
Stage
Late-stage private / Series G growth financing
Total raised
$1.5B
Latest round
Series G · Jun 2026
Latest amount
$465M
Jun 2026 · Thrive Capital
Jan 2025 · Not publicly established; Lightspeed and SoftBank Vision Fund 2 participated
Sep 2023 · Not publicly established
Nov 2021 · Sam Altman
Jan 2020 · Dustin Moskovitz / Good Ventures
Jan 2019 · Capricorn Investment Group
Jan 2016 · Not publicly established
Jan 2015 · Not publicly established
Aug 2014 · Y Combinator / Mithril Capital Management
NASA, U.S. Department of Energy and U.S. Department of Defense
Leadership
Co-founder & CEO
Co-founder & CTO
Co-founder & Chief Scientist / Principal Scientist
Co-founder
Chief Financial Officer
Lynn Miller
General Counsel
Savanna Thompson
Chief Business Operations Officer
Founders
John Slough
Co-founder
Investors
Official recruiting materials describe an intense, hardware-centric, execution- and speed-oriented culture focused on building first-of-a-kind machines, ownership, urgency, cross-functional problem solving and commercial deployment rather than open-ended research. Most roles appear facility-based in Washington; the company does not publish a general remote-work policy.
Work style
Onsite
Compensation
Helion advertises competitive salary, annual performance-based increases, a 5% 401(k) match and equity through stock options for all employees. Public sources reviewed did not provide reliable salary bands or confirm visa sponsorship.
Benefits
Pricing
Not publicly disclosed; expected to be negotiated project/electricity offtake pricing rather than a published software-style price list.
Differentiators
Technology
Customers
Competitors
Estimated monthly visits
78.6K
Independent reporting noted that Helion has not publicly demonstrated net electricity from Polaris, despite earlier targets, and that scaling from prototype results to a 50-MW commercial plant by the Microsoft timetable remains technically and operationally uncertain.
SourcePolaris achieved measurable D-T fusion and 150 million °C plasma, but Helion described these as milestones in a continuing test program; commercial D-He-3 operation and net grid electricity remain future objectives.
SourceHelion obtained Washington licenses for radioactive materials and air emissions at Orion, a positive regulatory milestone, but still identified transmission interconnection and further construction as remaining steps before grid delivery.
SourceHelion newsroom · Jun 2026
Helion announced Washington State radioactive-materials and air-emissions licenses for Orion, allowing the project to proceed with further construction while transmission interconnection work continues.
Helion newsroom · Jun 2026
Thrive Capital led a $465 million Series G at a $15.5 billion post-money valuation, bringing reported total investment to $1.5 billion.
Scientific American · May 2026
An independent assessment highlighted Helion's progress and commercial ambition while noting that net electricity from Polaris had not been publicly confirmed and that the 2028 delivery target remains uncertain.
Helion newsroom · Feb 2026
Polaris demonstrated measurable D-T fusion and reached 150 million °C, while Helion said testing would continue toward its commercial D-He-3 operating objectives.
Reuters · Jul 2025
Reuters reported Helion began construction on its Orion fusion plant in Malaga, Washington, intended to supply Microsoft data centers by 2028.
62 jobs at Helion Energy