Current state
| Status | Commissioning |
| Design | VVER-1000 (PWR) |
| Net capacity | 917 MWe |
| Country | India |
| Vendor | Rosatom |
| Owner / operator | Nuclear Power Corporation of India (NPCIL) |
| Construction start | 2017-06-29 |
| Original COD target | 2023 |
| Current COD estimate | 2027 |
| Schedule slippage | +4 years |
Notes
Government's official revised COD is June 2027 (PIB Rajya Sabha answer, 2026-08-13), superseding the plant director's 2026 ambition; revised cost Rs 68,893 crore. 'Spillage to open reactor' completed June 2026; fuel loading not yet reported — unit remains in pre-fuel commissioning. Units 4-6 need separate entries.
Milestone log
- 2017-06-29 — First concrete, Unit 3 (source)
- 2025-12-10 — First fuel batches delivered to site for Unit 3 (source)
- 2026-04-25 — 'Spill to open reactor' commissioning milestone reached (source)
- 2026-06-30 — 'Spillage to Open Reactor' — flushing of passive and active safety systems and main coolant pipelines — completed, per NPCIL monthly achievements (source)
- 2026-08-13 — PIB Rajya Sabha written answer (DAE Minister): KKNPP-3 commissioning revised from original Mar-2023 to Jun-2027; revised cost Rs 68,893 crore (from Rs 39,849 crore) (source)
The milestone log is append-only: corrections are recorded as new entries, never rewrites. Full history via /api/v1/changes.
NNN coverage
On the VVER-1000 design
Sources
- https://world-nuclear.org/information-library/current-and-future-generation/plans-for-new-reactors-worldwide
- https://pris.iaea.org/pris/
- https://www.world-nuclear-news.org/articles/flushing-of-safety-systems-begins-for-kudankulam-unit-3
- https://www.npcil.nic.in/WriteReadData/userfiles/file/MA_News_30072026_01.pdf
- https://www.pib.gov.in/PressReleasePage.aspx?PRID=2298859
- https://www.neimagazine.com/news/active-commissioning-for-kudankulam-3/