Helion Energy
YC S14Seattle, US · Founded 2013 · Delaware corporation · 150 employees · 13 known investors
Find your way into Helion Energy
915 people in our graph share verified history with the Helion Energy team — schools, employers, funds. One of them is your warm intro.
Alex Chachavaunlockedknows David Kirtley · together at YPO (overlapped)
×4knows the team · via University of Washington
×5knows the team · via Y Combinator
knows the team · via Helion Energy
knows the team · via YPO
Helion develops fusion energy systems designed to generate clean electricity for commercial use. The company builds pulsed magnetic fusion prototypes with applications for industrial and commercial electricity generation.
Also known as Helion
Advanced ManufacturingCleantechClimate TechDeep TechEnergyHardwareFusion EnergyHard TechClimateUnited States of AmericaAmerica / Canada
Founders & leadership· Y Combinator alumni (S14)
Helion Energy was founded in 2013 by David Kirtley, Chris Pihl, John Slough, George Votroubek, and Anthony Pancotti.
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David Kirtleyin𝕏Founder and CEOFounder and CEO of Helion Energy, a privately funded company developing fusion energy systems—pulsed magnetic fusion prototypes—to generate clean electricity for commercial and industrial use.
CP
Chris PihlinCo-Founder, CTOCo-founder and CTO of Helion Energy, which develops pulsed magnetic fusion systems to generate electricity for commercial and industrial use.
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John SloughinCo-founderformer
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George VotroubekinCo-Founder & Chief ScientistCo-founder and Chief Scientist of Helion Energy, which develops pulsed magnetic fusion systems for commercial and industrial electricity generation.
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Anthony PancottiinCo-FounderCo-founder of Helion Energy, which develops pulsed magnetic fusion prototypes aimed at generating clean electricity for industrial and commercial use.
Board
SA
AR
Investors · 13
AntiSan Juan · $250K – $30M
Congruent VenturesSan Francisco · $100K – $5M
SoftBank GroupTokyo
SoftBank Vision FundLondon
Y CombinatorSan Francisco · $500K
Capricorn Investment Groupreported · 2 sourcesNew York
Lightspeed Venture PartnersreportedMenlo Park · $1.7M – $87M
Lux CapitalreportedNew York · $100K – $100M
Mithril Capital Managementreported · 4 sourcesAustinvia Ajay Royan · board
Sam Altmanreported
Thrive CapitalreportedNew York · $500K – $25M
Also in the syndicate · 2
NucorSoftBank Vision Fund 2
Funding
SEC filings, press & company announcements$477.1M disclosed across 3 of 6 rounds · 2014–2026
- Undisclosed amountSeries GJun 2026Source ↗
- $465MraisedJun 2026 · 3 sourcesSource ↗
- Undisclosed amountSeries FJan 2025
Capricorn Investment Group, Lightspeed Venture Partners, Mithril Capital, Nucor, SoftBank Vision Fund 2
Source ↗
▶$10.6MraisedJul 2015 · 6 investors · OtherRule 506(b)
▶$10.6MraisedJul 2015 · 6 investors · Other
Rule 506(b)Officers, directors & promoters on the filing
- John SloughExecutive Officer, Director
- Christopher PihlExecutive Officer, Director
- Sam AltmanDirector
- Ajay RoyanDirector
- David KirtleyExecutive Officer, Director
- Offering amount
- $21.2M
- Amount sold
- $10.6M
- First sale
- Jun 2015
- Incorporated
- Corporation, Delaware, 2013
- Federal exemptions
- 06b
▶$1.5MraisedAug 2014 · 3 investors · OtherRule 506(b)
▶$1.5MraisedAug 2014 · 3 investors · Other
Rule 506(b)Officers, directors & promoters on the filing
- Christopher PihlExecutive Officer, Director
- John SloughExecutive Officer, Director
- Ajay RoyanDirector
- David KirtleyExecutive Officer, Director
- Offering amount
- $1.5M
- Amount sold
- $1.5M
- First sale
- Jul 2014
- Incorporated
- Corporation, Delaware, 2013
- Federal exemptions
- 06b
Source: SEC EDGAR Form D. Amounts as filed; amended filings shown once at their latest values.
Founder mafia
3 people who came through Helion Energy went on to found or lead other companies.
Competitors · 1
by search overlap
Companies competing with Helion Energy for the same Google search keywords, organic and paid, via search-intersection analysis.
In the news
Helion Energy - Wikipediaen.wikipedia.org · Aug 2026
Fusion roundup: Helion sets temperature record; Inertia raises $450M -- ANS / Nuclear Newswireans.org · Jul 2026
Fusion Energy Attracts $4.5 Billion in a Year; General Fusion Surges on Second Day of Nasdaq Trading — BigGo Financefinance.biggo.com · Jul 2026
Helion Energy Raises $425 Million to Build World's First Nuclear Fusion Power Plant - London Dailylondondaily.com · Jul 2026Frequently asked questions
- What does Helion Energy do?
- Helion develops fusion energy systems designed to generate clean electricity for commercial use. The company builds pulsed magnetic fusion prototypes with applications for industrial and commercial electricity generation.
- Who founded Helion Energy?
- Helion Energy was founded by David Kirtley, Chris Pihl, John Slough, George Votroubek, Anthony Pancotti in 2013.
- Who are Helion Energy's investors?
- Helion Energy's investors include Anti, Congruent Ventures, SoftBank Group, SoftBank Vision Fund, Y Combinator, Capricorn Investment Group, Lightspeed Venture Partners, Lux Capital and 3 more.
- How much funding has Helion Energy raised?
- Helion Energy has disclosed $477.1M raised across 3 of its 6 known rounds.
- Where is Helion Energy headquartered?
- Helion Energy is headquartered in Seattle, US.