Nuclear reactors supplied by Siemens / Kraftwerk Union
Siemens / Kraftwerk Union is recorded as the nuclear steam supply system (NSSS) supplier of 29 units in 6 countries, per the IAEA PRIS register: 6 operating with 4,793 MWe net, 1 under construction and 22 shut down.
Germany's pressurized and boiling water reactors, and the pressure-vessel PHWRs at Atucha. By country: Germany (22), Argentina (2) and Brazil (2). By technology: 18 PWR, 8 BWR and 3 PHWR. The first unit was connected in 1966 and the most recent in 2014. The most powerful unit in operation is Angra 2, in Brazil, with 1,275 MWe. One unit is under construction: Angra 3 (Brazil). 22 units have been permanently shut down.
PRIS supplier codes: KWU, SIEMENS, S/KWU, SIEM,KWU, AEG,KWU, AEG · Reference · Names per IAEA, Nuclear Power Reactors in the World 2025, table 25
Units with a Siemens / Kraftwerk Union nuclear steam supply system
| Unit | Country | Type | Model | MWe | Grid connection | Status |
|---|---|---|---|---|---|---|
| MZFR |  Germany | PHWR | — | 52 | 1966 | Shut down |
| Lingen | Germany | BWR | BWR with fossil fuel-fired superheater | 183 | 1968 | Shut down |
| Obrigheim | Germany | PWR | Siemens | 340 | 1968 | Shut down |
| Wuergassen | Germany | BWR | BWR-69 (AEG) | 640 | 1971 | Shut down |
| Stade | Germany | PWR | Siemens | 640 | 1972 | Shut down |
| Borssele 1 |  Netherlands | PWR | KWU 2LP | 482 | 1973 | Operating |
| Atucha 1 |  Argentina | PHWR | Siemens-KWU (PHWR KWU) | 335 | 1974 | Operation suspended |
| Biblis A | Germany | PWR | unknown | 1,167 | 1974 | Shut down |
| Biblis B | Germany | PWR | unknown | 1,240 | 1976 | Shut down |
| Brunsbuettel | Germany | BWR | KWU BWR, '69 design line (BWR-69) | 771 | 1976 | Shut down |
| Neckarwestheim 1 | Germany | PWR | Siemens-KWU (KWU) | 785 | 1976 | Shut down |
| Isar 1 | Germany | BWR | KWU BWR, '69 design line (BWR-69) | 878 | 1977 | Shut down |
| Unterweser | Germany | PWR | Siemens-KWU (KWU) | 1,345 | 1978 | Shut down |
| Philippsburg 1 | Germany | BWR | KWU BWR, '69 design line (BWR-69) | 890 | 1979 | Shut down |
| Goesgen |  Switzerland | PWR | Siemens-KWU 3-loop (PWR 3LP) | 1,010 | 1979 | Operating |
| Grafenrheinfeld | Germany | PWR | Siemens-KWU (KWU) | 1,275 | 1981 | Shut down |
| Kruemmel | Germany | BWR | KWU BWR, '69 design line (BWR-69) | 1,346 | 1983 | Shut down |
| Grohnde | Germany | PWR | Siemens-KWU (KWU) | 1,360 | 1984 | Shut down |
| Gundremmingen B | Germany | BWR | KWU BWR, '72 design line (BWR-72) | 1,284 | 1984 | Shut down |
| Gundremmingen C | Germany | BWR | KWU BWR, '72 design line (BWR-72) | 1,288 | 1984 | Shut down |
| Philippsburg 2 | Germany | PWR | Siemens-KWU (KWU) | 1,402 | 1984 | Shut down |
| Brokdorf | Germany | PWR | Siemens-KWU (KWU) | 1,410 | 1986 | Shut down |
| Emsland | Germany | PWR | Konvoi (Siemens-KWU) (Konvoi) | 1,335 | 1988 | Shut down |
| Isar 2 | Germany | PWR | Konvoi (Siemens-KWU) (Konvoi) | 1,410 | 1988 | Shut down |
| Trillo 1 |  Spain | PWR | Siemens-KWU 3-loop (PWR 3LP) | 1,003 | 1988 | Operating |
| Neckarwestheim 2 | Germany | PWR | Konvoi (Siemens-KWU) (Konvoi) | 1,310 | 1989 | Shut down |
| Angra 2 |  Brazil | PWR | Pre-Konvoi (Siemens-KWU) (PRE KONVOI) | 1,275 | 2000 | Operating |
| Atucha 2 | Argentina | PHWR | Siemens-KWU (PHWR KWU) | 688 | 2014 | Operating |
| Angra 3 | Brazil | PWR | Pre-Konvoi (Siemens-KWU) (PRE KONVOI) | 1,340 | 2033 | Under construction |
Data: Global Energy Monitor (CC BY 4.0), IAEA PRIS 2025, Wikipedia (CC BY-SA), Wikidata and Wikimedia Commons. Capacities in net MWe unless stated.
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