BKW shut the Mühleberg BWR on 20 December 2019, the first Swiss power reactor to be decommissioned, and began dismantling on 6 January 2020. All 418 fuel assemblies were moved to the Würenlingen store by September 2023; work costing about CHF 800m should be done in 2031, with the site free for reuse from 2034.
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Current state
| Status | Active dismantling |
| Country | Switzerland |
| Location | Mühleberg, Bern |
| Site | Mühleberg |
| Units | KKM |
| Unit count | 1 |
| Reactor types | BWR |
| Owner / licensee | BKW Energie AG |
| Strategy | Immediate dismantling |
| Final shutdown | 2019-12-20 |
| Decommissioning start | 2020-01-06 |
| Target completion | 2031 |
| Cost estimate | CHF 800m (as of 2026-10) |
| Spent fuel | All 418 fuel assemblies at the central Zwilag store in Würenlingen since September 2023. |
Notes
Cost per WNA (page updated 2026-10-09); a further CHF 1.3bn is budgeted for waste disposal, and BKW's decommissioning fund held CHF 930m (date not given, so not recorded).
Timeline
- 2013-10 — BKW decided to operate Mühleberg until end-2019 and then decommission it. (source)
- 2019-12-20 — Power operation permanently ended. (source)
- 2020-01-06 — Dismantling began. (source)
- 2023-09 — The last fuel assemblies left the site for Würenlingen. (source)
- 2024-10 — Cutting and packaging of activated control rods was completed. (source)
The timeline is append-only: corrections are added as new entries. Stated targets appear in the current-state table, never as milestones.
Related sites
- Biblis Nuclear Power Plant (Units A and B) Active dismantling · Germany
- Brokdorf Nuclear Power Plant (KBR) Active dismantling · Germany
- Brunsbüttel Nuclear Power Plant (KKB) Active dismantling · Germany
- Chinshan Nuclear Power Plant Fuel removal · Taiwan
- Chooz A Active dismantling · France
- Crystal River Unit 3 Site restoration · United States
- Doel Nuclear Power Plant (Units 1-3) Shut down · Belgium
- Dounreay (DFR and PFR fast reactors) Active dismantling · United Kingdom
See all 72 sites in the Nuclear Decommissioning Tracker →
Sources
- Stilllegung Kernkraftwerk Mühleberg — BKW (primary), checked 2026-10-11
- Nuclear Power in Switzerland — World Nuclear Association, checked 2026-10-11