Source: PIB Backgrounder, April 7, 2026
The indigenously designed and built Prototype Fast Breeder Reactor (PFBR) at Kalpakkam, Tamil Nadu attained first criticality on April 6, 2026. With it, India formally enters Stage 2 of the three-stage nuclear power programme conceived by Dr. Homi Jehangir Bhabha, and becomes only the second country after Russia to operate a commercial-scale fast breeder reactor.
The Three-Stage Logic
| Stage | Reactor type | Fuel strategy |
|---|---|---|
| 1 | Pressurised Heavy Water Reactors | Natural uranium; produces plutonium |
| 2 | Fast Breeder Reactors (PFBR) | Uranium-Plutonium MOX; breeds more fuel than it burns (U-238 blanket breeds Pu-239) |
| 3 | Thorium reactors | Th-232 breeds U-233, unlocking India’s vast thorium reserves |
The PFBR is the bridge: its blanket assemblies will later carry Thorium-232, generating the Uranium-233 that Stage 3 needs.
Who Builds, Who Designs
- BHAVINI (Bharatiya Nabhikiya Vidyut Nigam Limited) built and operates the 500 MWe unit at the Kalpakkam nuclear complex
- IGCAR (Indira Gandhi Centre for Atomic Research) developed the technology, under the Department of Atomic Energy
- Construction was sanctioned in 2003; criticality marks the move from construction to operations
The Capacity Roadmap
- Current installed nuclear capacity: 8.78 GW; generation 56,681 million units in 2024-25 (3.1 percent of electricity)
- Projected: 22.38 GW by 2031-32
- Nuclear Energy Mission (Budget 2025-26): 100 GW by 2047, with Rs 20,000 crore for Small Modular Reactors; at least 5 indigenous SMRs by 2033 (BARC designs: BSMR-200, SMR-55, and a high-temperature gas-cooled reactor for hydrogen)
- SHANTI Act, 2025 enables limited private participation; India has civil nuclear cooperation agreements with 18 countries
Mains Angle
Why it matters: fast breeders multiply the energy extracted from India’s limited uranium and make the thorium economy reachable; nuclear is the firm, low-carbon base the 2070 net-zero pathway needs. Risks to weigh: FBR economics remain unproven globally (most countries abandoned them), sodium-cooled systems carry unique safety engineering demands, and the 100 GW target requires a build rate India has never sustained.
📌 Facts Corner — Knowledgepedia
PFBR:
- 500 MWe; first criticality April 6, 2026; Kalpakkam, Tamil Nadu
- Built by BHAVINI; technology by IGCAR; fuel: Uranium-Plutonium MOX
- India: second country after Russia with a commercial fast breeder
Programme and targets:
- Three-stage programme: PHWR, FBR, thorium reactors (Bhabha)
- Installed nuclear: 8.78 GW (3.1 percent of electricity); 22.38 GW by 2031-32; 100 GW by 2047
- Nuclear Energy Mission: Rs 20,000 crore for SMRs; 5 indigenous SMRs by 2033
- SHANTI Act 2025: limited private participation; 18 civil nuclear cooperation agreements
Sources: PIB, Department of Atomic Energy
