PFBR Kalpakkam and India’s Three-Stage Nuclear Programme
Why in the news
India’s atomic energy plan is entering Stage II, because the sodium-cooled PFBR (500 MW) in Kalpakkam, Tamil Nadu is close to commissioning. It bridges to the thorium stage that Homi Bhabha outlined in 1954.
Key facts
- Builder: BHAVINI (set up 2003); design by IGCAR, Kalpakkam.
- Fuel: plutonium-uranium MOX made from spent PHWR fuel; coolant: liquid sodium.
- Core loading began 4 March 2024; AERB cleared fuel loading and first criticality approach in July 2023.
- DAE’s timeline: criticality in 2025-26, complete commissioning by September 2026.
- Predecessor: 40 MWt Fast Breeder Test Reactor (1985); two more 600 MW fast units are planned there.
The three stages
| Stage | Reactor | Fuel and role |
|---|---|---|
| I | PHWR | Natural uranium; heavy water moderator and coolant; e.g. Rawatbhata, Kaiga, Kakrapar |
| II | Fast breeder | Plutonium from PHWR spent fuel; blanket of U-238 and thorium breeds more plutonium and U-233 |
| III | Thorium reactors | U-233 from thorium, e.g. Advanced Heavy Water Reactor; India holds about 25% of world thorium |
- Kudankulam’s Russian VVERs are light water reactors and fall outside this line.
Roadmap
- Installed: about 8.18 GW; 7.30 GW under construction; 7 GW pre-project; goal 22.48 GW by 2031-32.
- Long-term aim of about 55 GW: 15.40 GW PHWRs, 17.60 GW light water reactors with foreign help, 3.80 GW fast breeders, plus SMRs and Bharat Small Reactors.
- Nuclear Energy Mission (Budget 2025-26, ₹20,000 crore): 100 GW by 2047, five indigenous SMRs by 2033, and amendments to the Atomic Energy Act and Civil Liability for Nuclear Damage Act for private entry.
Significance
- Closed fuel cycle multiplies energy from limited uranium.
- Energy security, clean baseload power and near-complete self-reliance.
Exam angle
- Breeder: makes more fissile material than it consumes; sodium is used since it does not slow neutrons but reacts violently with water and air.
- Stage order: PHWR, then FBR, then thorium.