Energy paper

Fusion energy

Fusion went from public-science promise to active commercial track between 2022 and 2026: NIF demonstrated repeatable net energy gain, CFS broke ground on SPARC with HTS magnets, and Helion shipped a D-T plasma machine on the way to a 50 MW commercial PPA with Microsoft.

What to watch next

First private-fusion net-electricity-on-grid demonstrations (CFS SPARC Q>1 in 2027, Helion Orion 2028), AI plasma control becoming standard, and validation of tritium breeding fuel-cycle infrastructure at commercial scale.

Key sub-ideas & techniques

• Tokamak (magnetic confinement) — The most-developed fusion approach: a toroidal magnetic chamber confines a hot plasma. CFS SPARC, ITER, KSTAR/EAST, JT-60SA, and DIII-D are the major active programs. [source]
• Inertial confinement (laser-driven) — High-energy lasers compress a fusion fuel pellet to ignition. NIF reached repeatable net energy gain (8.6 MJ from 2.08 MJ in April 2025) — the first machine of any kind to do so. [source]
• HTS (high-temperature superconductor) magnets — Rare-earth barium copper oxide (REBCO) tape enables 20+ tesla magnetic fields, cutting tokamak size and cost dramatically — the enabling technology for compact commercial fusion machines. [source]
• AI plasma control — Deep RL controllers stabilize plasma in real time on DIII-D, KSTAR, and TCV; DeepMind's TORAX simulator (May 2024) is now part of CFS's planning loop and broadly adopted across the field. [source]
• Alternative confinement concepts — Field-reversed configuration (Helion, 150M°C D-T, Feb 2026), sheared-flow Z-pinch (Zap Energy, 1.6 GPa pressures), stellarators (Wendelstein 7-X, 43s record May 2025), and acoustically driven MTF (General Fusion). [source]

Current frontier

• NIF achieved 10+ ignition shots with a peak yield of 8.6 MJ (April 2025) — establishing repeatable net energy gain and a target-gain trend above 4:1 for inertial confinement fusion. [source]
• Commonwealth Fusion Systems installed the first of 18 toroidal-field HTS magnets on SPARC in Jan 2026; first plasma is targeted for 2026 with a Q>1 demonstration in 2027. [source]
• Helion Polaris reached 150 million °C with deuterium-tritium fuel (Feb 2026) — the first privately-built D-T fusion machine; Orion commercial plant construction began Jul 2025 with a 50 MW Microsoft PPA targeting 2028. [source]
• KSTAR set a 100 million °C, 48-second plasma record (2024) with a 300-second target by 2026; Wendelstein 7-X reached a 43-second high-fusion-product plasma in May 2025. [source]
• AI/RL plasma control was demonstrated on DIII-D and KSTAR in 2024; DeepMind's TORAX simulator (May 2024) is now embedded in CFS's daily operational planning and adopted across the field. [source]
• A desktop-scale (sub-5-inch) electrostatic/magnetic 'orbitrap' fusion device heated plasma to roughly 11 million degrees C (above 1 keV apparent ion temperature) on less than $50M of investment, demonstrating a compact path toward fusion conditions. [source]

Key people

• Omar Hurricane Chief Scientist, Inertial Confinement Fusion Program · Lawrence Livermore National Laboratory [source]
• Bob Mumgaard Co-founder & CEO · Commonwealth Fusion Systems [source]
• David Kirtley Co-founder & CEO · Helion Energy [source]
• Michel Laberge Founder & CTO · General Fusion [source]
• Pietro Barabaschi Director-General · ITER Organization [source]
• Sam Altman Chairman of the Board · Helion Energy (also CEO, OpenAI) [source]

Startups & labs to watch

• Commonwealth Fusion Systems (SPARC) CFS (MIT spinout) · STARTUP · $3.0B total; Series B2 $863M (Aug 2025) led by Nvidia, Google, Bill Gates — Largest private fusion effort: $3B+ raised, magnet assembly underway, first plasma targeted 2026 and Q>1 in 2027 — closest to a credible commercial tokamak. [source]
• Helion Energy (Polaris / Orion) Helion Energy · STARTUP · Series E+ via Sam Altman, Khosla Ventures; Microsoft PPA May 2023 — Only private firm with a firm grid PPA (Microsoft 50 MW by 2028); FRC achieved 150M°C D-T (2026); Orion commercial plant under construction. [source]
• TAE Technologies (Norm / Copernicus) TAE Technologies · STARTUP · $1.3B+ equity raised; $150M latest round (Chevron, Google, NEA) — Neutral-beam injection breakthrough (Apr 2025) cut machine complexity ~50%; Copernicus targeting net energy before 2030; planned TMTG-style merger at $6B valuation (mid-2026). [source]
• Tokamak Energy (ST40 / Demo4) Tokamak Energy · STARTUP · Multiple rounds; UK government and private capital — Spherical tokamak architecture with 11.8-tesla HTS magnets; claims 30–40× smaller plasma volume vs LTS designs and a clear path to ST-E1 commercial pilot. [source]
• Thea Energy Thea Energy · STARTUP · $100M (May 27, 2026); leads Prelude Ventures, US Innovative Technology, General Innovation Capital Partners — Planar-coil stellarator as a simpler-to-manufacture alternative to tokamaks; $100M to build a demonstration prototype amid AI-data-center power demand. [source]
• Focused Energy Focused Energy GmbH (Germany / Austin, TX) · STARTUP · $240M Series A (June 2026) led by RWE; ~$300M private + $200M grants total — Now one of the most heavily funded fusion startups; inertial-confinement laser fusion using direct-drive targets at high rep-rate, building a 'Lighthouse' demo at a former RWE nuclear site. [source]