ITER is the 35-nation intergovernmental tokamak under construction in southern France, designed to produce 500 MW of fusion power (Q=10). Under the 2024 baseline, research operations start in 2034 and deuterium-tritium operation in 2039; by July 2026 six of nine vacuum-vessel sector modules were in the tokamak pit.
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Current state
| Status | Under construction |
| Country | France |
| Location | Saint-Paul-lez-Durance (Cadarache), Provence |
| Developer | ITER Organization (EU, China, India, Japan, Korea, Russia, US) |
| Developer type | Public |
| Concept | Tokamak |
| Fuel | D-T |
| Purpose | Research |
| First plasma target | 2034 |
| Net energy target | 2039 |
| Site | Under construction at Cadarache; tokamak assembly ~two-thirds of vacuum vessel modules installed |
| Public funding | Intergovernmental: Europe ~45% of construction cost as host; six other members share the rest equally (largely in-kind) |
| Regulation | Licensed by the French nuclear safety authority (ASN, now ASNR) as a basic nuclear installation (INB); the 2024 baseline required a revised safety file. |
Notes
first plasma target holds the 2034 Start of Research Operation (D-D, with full plasma current ~2036); net energy target holds the 2039 start of D-T operation, when Q=10 (Q_sci, not Q_eng) is pursued. ITER will not generate electricity. Official total cost not published; the €5bn rebaseline increase is a press estimate.
Timeline
- 2024-07 — ITER presented its Baseline 2024: Start of Research Operation in 2034 and deuterium-tritium operation in 2039, replacing the 2025 first-plasma date. (source)
- 2024-07 — The rebaseline was reported to add about €5 billion to costs, with a switch from beryllium to tungsten first wall. (source)
- 2025-04 — ITER completed all its cryopumps as SPARC's assembly began, per World Nuclear News. (source)
- 2026-07-28 — ITER lowered the sixth of nine vacuum-vessel sector modules into the pit, putting two-thirds of the tokamak core in place; final module now expected mid-2027. (source)
- 2026-09 — ITER reported substantial progress in assembly and installation work, including preparations for vacuum-vessel welding. (source)
The timeline is append-only: corrections are added as new entries. Stated targets appear in the current-state table, never as milestones.
NNN coverage
About ITER Organization
Related projects
- ARC (Commonwealth Fusion Systems) Design · United States
- BEST (Burning Plasma Experimental Superconducting Tokamak) Under construction · China
- CFEDR / China Fusion Energy Co. demo reactor (successor to CFETR) Design · China
- EAST (Experimental Advanced Superconducting Tokamak) Operating · China
- EU DEMO (EUROfusion Demonstration Power Plant) Concept · European Union
- FAST (Fusion by Advanced Superconducting Tokamak) Design · Japan
- HH170 (Energy Singularity) Design · China
- HH70 (Energy Singularity) Operating · China
See all 51 projects in the Fusion Energy Companies & Projects Tracker →
Sources
- Baseline press conference summary, July 2024 — ITER Organization (primary), checked 2026-10-11
- Two-thirds of ITER tokamak core now in place — ITER Organization (primary), checked 2026-10-11
- ITER fusion reactor hit by massive decade-long delay and €5bn price hike — Physics World, checked 2026-10-11
- ITER reports 'substantial progress' in assembly and installation work — ANS Nuclear Newswire, checked 2026-10-11
- Assembly starts of SPARC, as ITER cryopumps completed — World Nuclear News, checked 2026-10-11