The brief
- Polaris, its seventh prototype, reported measurable D-T fusion at 150 million °C in February 2026.
- Building its Orion plant in Malaga, Washington; got state operating licences in June 2026.
- Signed the first fusion power deal (Microsoft, 50 MW from 2028) and a 500 MW plant deal with Nucor.
Technical approach
Colliding plasma rings
Two self-contained plasma rings (FRCs) are fired at each other at hundreds of km/s. They merge in the middle, turning speed into heat.
A pulsed magnetic squeeze
Magnets then squeeze the merged plasma in about a millisecond to fusion conditions. It runs in pulses, like an engine.
Electricity straight from the plasma
Fusion makes the plasma push back on the magnets, inducing current that flows back into capacitors. No steam cycle needed.
Deuterium-helium-3 fuel
Long term it wants D-He3 fuel, which gives off few neutrons. Helium-3 is scarce, so Helion plans to make it from D-D fusion.
Helion, two programs
Updated 8 Sep 2026
Research & demos
- Feb 2026
First private machine to report measurable D-T fusion, backing Helion's approach at scale.
- 2021
Its sixth prototype reached fusion-level temperatures in a privately built FRC machine.
Open technical problems
- Getting net electricity outActive research
Helion must get back more energy than it spends forming and squeezing the plasma, pulse after pulse, fast enough for a plant.
- Electronics that pulse millions of timesActive research
A plant needs huge capacitor banks and switches that survive millions of pulses; nobody has shown they last.
- Helium-3 supplyOpen
Earth has very little helium-3, so the plan depends on making enough of it in D-D fusion reactions.
Upcoming catalysts
- 2028Orion due to start delivering power to MicrosoftOrionby ~27 mo
Peers
Company & funding
- Valuation
- $5.4Bprivate
- Raised
- $925Mdisclosed private rounds
- Last round
- Series FJan 2025
- HQ
- US
- Founded
- 2013
| Date | Round | Amount | Post-money | Lead |
|---|---|---|---|---|
| Jan 2025 | Series F | $425M | $5.4B | — |
| Nov 2021 | Series E | $500M | — | Sam Altman |
Partners & customers
- Customer
2023 PPA for at least 50 MW from Helion's first plant starting 2028
- Customer
2023 agreement to develop a 500 MW fusion plant at a Nucor steel site
- Partner
Power marketer for Orion's output to Microsoft
- Investor
Led the 2021 Series E and chairs Helion's board
People
- David Kirtley (opens helionenergy.com)Co-founder & CEO