Unterweser, a single 1,345 MWe PWR that once held the world record for lifetime output from a single unit, was shut in March 2011. PreussenElektra has been dismantling it since February 2018, cut up the reactor vessel from 2022 and began removing the four steam generators in May 2025.
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Current state
| Status | Active dismantling |
| Country | Germany |
| Location | Stadland, Lower Saxony |
| Site | Unterweser |
| Units | KKU |
| Unit count | 1 |
| Reactor types | PWR |
| Net capacity (MWe) | 1,345 |
| Owner / licensee | PreussenElektra (E.ON) |
| Strategy | Immediate dismantling |
| Final shutdown | 2011-08-06 |
| Decommissioning start | 2018-02 |
| Notable issue | About 675,000 tonnes of demolition material to manage. |
Notes
675,000 t figure from NDR. Legal shutdown date 2011-08-06 per WNA (operation ended March 2011).
Timeline
- 2011-03 — Unterweser was shut down along with seven other German plants. (source)
- 2018-02 — Nuclear dismantling began with the granting of the decommissioning and dismantling permit. (source)
- 2022-08 — The 400-tonne reactor pressure vessel was lifted out for segmentation. (source)
- 2025-05 — Removal of the four ~300-tonne steam generators began. (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
- Kernkraftwerk Unterweser — PreussenElektra (primary), checked 2026-10-11
- Nuclear Power in Germany — World Nuclear Association, checked 2026-10-11
- Wie geht das? Ein Atomkraftwerk zurückbauen — NDR, checked 2026-10-11