Nuclear Fusion
No plant anywhere has put electricity on a grid yet — this field is a genuine toss-up.
ITER, the flagship international project, just had its first-plasma milestone pushed from 2025 to 2034. No commercial fusion plant has produced grid electricity anywhere, and no company is within twelve months of doing so. The real momentum is split between a large U.S. private sector and China’s state-scale investment — genuinely too early to call a winner.
Standings
Home to 25 of the roughly 45 private fusion companies tracked globally — the deepest bench of private capital and technical attempts, even though none is within twelve months of grid electricity.
Building multiple reactors, including a large state-backed facility in Sichuan province, with fusion research investment explicitly aimed at global leadership — a state-scale bet against the U.S.’s private-sector-led approach.
The largest single physical fusion project in the world by far, now targeting first plasma in 2034 rather than 2025 — the most scientifically ambitious of the three approaches, and the slowest-moving by calendar time.
Key facts
- ITER’s first-plasma milestone has slipped from 2025 to 2034 — Congressional Research Service
- ~45 private fusion companies globally, 25 of them in the U.S. — Fusion industry survey aggregation
How this ranking was determined
No standardized capacity or output metric exists yet for fusion, so this ranking is an editorial judgment based on company count, funding depth, and publicly stated timelines — not a measurement. Treat the order as directional, not authoritative.