PFBR at Kalpakkam Achieves First Criticality — A Historic Leap in India’s Nuclear Journey
Converts Uranium-238 into Plutonium-239, effectively creating more fuel than it consumes
In a landmark achievement for India’s nuclear energy programme, the 500 MWe Prototype Fast Breeder Reactor (PFBR) at Kalpakkam attained first criticality—the initiation of a controlled nuclear fission chain reaction—on April 6, 2026, at 08:25 PM. This milestone marks a decisive step toward strengthening long-term energy security and advancing indigenous nuclear technology under the aegis of the Department of Atomic Energy.
The criticality was achieved in the presence of Ajit Kumar Mohanty, Secretary, DAE & Chairman, AEC, along with senior officials from Indira Gandhi Centre for Atomic Research and Bharatiya Nabhikiya Vidyut Nigam Limited (BHAVINI), after receiving clearance from the Atomic Energy Regulatory Board following rigorous safety evaluations.
What Makes PFBR Special?
The PFBR represents cutting-edge indigenous innovation. Designed by Indira Gandhi Centre for Atomic Research and built by Bharatiya Nabhikiya Vidyut Nigam Limited, it uses Uranium-Plutonium Mixed Oxide (MOX) fuel and operates with fast neutrons—unlike conventional reactors.
Key highlights:
- Converts Uranium-238 into Plutonium-239, effectively creating more fuel than it consumes
- Future-ready to utilize Thorium-232, converting it into Uranium-233
- Employs liquid sodium coolant for high-temperature efficiency
- Supports a closed fuel cycle, enabling recycling of nuclear material and reducing waste
Backbone of India’s Three-Stage Nuclear Programme
India’s nuclear roadmap is built on a visionary three-stage strategy. The PFBR is the critical bridge between:
- Pressurized Heavy Water Reactors (current stage)
- Fast Breeder Reactors (second stage – PFBR)
- Thorium-based reactors (future stage)
This progression will enable India to fully harness its vast thorium reserves, ensuring long-term clean and sustainable energy independence.
A Boost to Atmanirbhar Bharat
The success of PFBR highlights India’s growing strength in:
- Advanced reactor design and engineering
- Nuclear fuel cycle technologies
- Indigenous manufacturing ecosystems
Developed largely with domestic expertise and components, the project reinforces the vision of self-reliance in strategic technologies.
Clean Energy & Strategic Impact
Fast breeder reactors like PFBR offer:
- Reliable base-load power with low carbon emissions
- Higher fuel efficiency compared to conventional reactors
- Reduced nuclear waste through recycling
Beyond energy, the programme strengthens India’s capabilities in reactor physics, advanced materials, and next-generation nuclear systems.
The Bigger Picture
The attainment of first criticality at Kalpakkam is more than a technical milestone—it signals India’s readiness to lead in advanced nuclear technology while securing a sustainable energy future aligned with the vision of Viksit Bharat.
