Helion Energy funding, valuation and investors

Overview

Helion Energy is a fusion power company headquartered in Everett, Washington, developing magneto-inertial fusion using deuterium and helium-3. Founded in 2013 by David Kirtley, John Slough, Chris Pihl, and George Votroubek, Helion has raised roughly $1.5B total and employs 500+ people. The company is constructing its Orion fusion power plant in Malaga, Washington — the first to clear key state radioactive-materials licenses — with a Microsoft power purchase agreement targeting 50 MW delivery starting 2028 and a Nucor agreement for a 500 MW plant in the 2030s. Helion closed a $465M round at a $15.5B valuation in June 2026 led by Thrive Capital, following a $425M Series F in January 2025 that valued the company at $5.425B.

Why Helion Energy is interesting

Helion cleared Washington regulatory licenses for its Malaga fusion plant, holds a Microsoft PPA for 50 MW by 2028, and raised $465M at a $15.5B valuation — fusion capital now funds construction, not just physics demos.

Product & use cases

Helion develops pulsed fusion generators producing zero-carbon electricity, vertically integrating reactor design, manufacturing (165,000+ sq ft Everett facility), and power-plant construction. Orion in Malaga is the first commercial plant under development.

• Microsoft data-center and grid power via 50 MW PPA starting 2028
• Nucor steel manufacturing decarbonization via 500 MW plant in the 2030s
• Dispatchable baseload clean power for AI-driven electricity demand growth
• Commercial fusion electricity replacing carbon-intensive grid generation

Key facts

• June 2026: $465M at $15.5B valuation led by Thrive Capital — ~$1.5B total raised
• Orion fusion plant in Malaga, WA cleared key Washington state regulatory licenses (Oct 2025)
• Microsoft PPA for 50 MW fusion power starting 2028; Nucor 500 MW plant planned 2030s
• 165,000+ sq ft manufacturing facility in Everett for reactor components
• Sam Altman serves as executive chairman; Lightspeed (/fund/lightspeed-venture-partners-nyc) joined Series F

Funding history (newest first)

Investors in our directory

Funds linked from Helion Energy's profile — open a fund page for stage focus and related deal articles.

Competitive landscape

Edge: Regulatory progress (Washington licenses cleared), signed offtake with Microsoft and Nucor, and vertically integrated manufacturing — rare combination of engineering milestones plus commercial contracts in fusion.

Fusion has multiple credible physics paths but few with signed utility offtake and plant construction underway. Helion's magneto-inertial approach and Microsoft/Nucor contracts differentiate it from pure-research peers, though all fusion companies face execution risk on first-of-a-kind plants.

• Commonwealth Fusion Systems direct

  Tokamak-based fusion with strong MIT roots and large funding; different physics approach, similar commercialization race.

• TAE Technologies direct

  Long-running fusion venture with alternative fuel cycles; less public progress on power-plant construction timelines.

• Advanced fission / SMRs alternative

  Small modular reactors offer nearer-term firm clean power but carry waste and public-perception tradeoffs fusion avoids.

• Pacific Fusion direct

  Newer fusion entrant with significant backing; competes for investor attention in the same commercialization window.

Notable stories

• Helion broke ground on the Orion plant in Malaga in July 2025 and became the first fusion company to clear Washington radioactive-materials handling licenses — CEO David Kirtley called it a step toward 'abundant, clean, safe, affordable energy.'
• Sam Altman led Helion's $500M Series E in 2021 while running OpenAI — linking two of the era's highest-variance bets on AI compute demand and fusion power supply.

Industries

Related funding articles

Venture Capital Tracker pieces that cover Helion Energy's financing or category context.

• Helion Energy's $465M at $15.5B: Fusion Power Gets Funded for Scale