Helion Energy

Type: Company — Private fusion startup

Helion Energy is the most aggressive commercial fusion company by timeline commitment. It has signed a power purchase agreement with Microsoft for 50 MW of fusion electricity by 2028 — the first commercial fusion PPA signed, and a deadline that would require Helion to achieve ignition, net energy, and commercial-scale power production in approximately 2 years from now (as of June 2026). The company is backed primarily by OpenAI CEO Sam Altman ($375M investment, largest private investment in a fusion company at the time).

Technical Approach

• Technology: Field-Reversed Configuration (FRC) — a compact form of magnetic confinement distinct from the tokamak approach
• Fuel: Deuterium-Helium-3 (D-He3) — if achievable, produces protons (easily captured as electricity) rather than neutrons (which require a steam cycle). The D-He3 fuel cycle would be the "cleanest" fusion approach but requires achieving much higher plasma temperatures.
• Polaris prototype: Helion's 7th prototype device. In 2025, Polaris demonstrated measurable deuterium-tritium (D-T) fusion and achieved 150 million°C plasma temperatures — the first private D-T fusion demonstration. Fortune (2026-02-13) reports the 150M°C milestone (≈10× the sun's core) and frames Polaris as "the first privately developed fusion machine to operate with deuterium-tritium fuel"; ~100M°C is the rough minimum threshold for sustained commercial fusion, which Polaris cleared. Evidence: weak (single news item, Fortune)

Microsoft PPA & Orion Plant

• PPA: Helion signed a PPA with Microsoft for 50 MW of fusion electricity, delivery target 2028
• Orion plant: Helion broke ground in July 2025 on the Orion fusion power plant site in Malaga, Washington state
• Timeline risk: The 2028 deadline requires commercial fusion in ~2 years; industry consensus views this as extremely aggressive. If missed, PPA likely includes performance penalties. Orion (50 MW) targets first grid electrons in 2028, widely seen as aggressive; as of late 2025 Polaris had not announced net energy production and reactor assembly for Orion had not begun. Helion's future target fuel is deuterium + helium-3. Evidence: weak (single news item, Fortune)

Funding

• Total raised: ~$2.2B
• Key investors: Sam Altman ($375M), OpenAI (equity), Dustin Moskovitz ($1.5B lead in 2021 round), Peter Thiel, others
• Valuation: ~$15.5B (per 2021 round structure)

Milestones

• Jul 2025: Broke ground on Orion plant, Malaga, WA
• 2025: Polaris demonstrated D-T fusion and 150 million°C plasma
• ~2027: Helion's internal first-plasma target for Orion
• 2028: Microsoft PPA target date for 50 MW delivery

Outstanding Questions

• What happens if Helion misses the 2028 deadline? (Financial penalties likely; credibility impact severe)
• Does D-He3 fusion at commercial temperatures require significantly longer timelines than D-T?
• Is the Malaga, WA site grid-connected adequately to transmit 50 MW to Microsoft's datacenters?
• How does Helion's FRC compare to CFS's tokamak in Q-factor terms? (Less publicly documented)
• With no net energy production announced as of late 2025 and Orion assembly not begun, what is the credible path to 50 MW of grid electrons by 2028?

Changelog

• 2026-06-24 — Compiled new sources (helion-polaris-150m-milestone)