PM Modi Hails ‘Historic Milestone’ as Kalpakkam Fast Breeder Reactor Achieves First Criticality

New Delhi: Prime Minister Narendra Modi on Sunday praised Indian scientists for achieving “first criticality” at the Prototype Fast Breeder Reactor (PFBR) in Kalpakkam, calling it a landmark moment in the country’s nuclear energy journey.

Speaking during the 133rd episode of Mann Ki Baat, Modi described the achievement as a “historic milestone” that strengthens India’s vision of a developed nation, or Viksit Bharat. He highlighted that the reactor has been built entirely using indigenous technology, marking a significant step in self-reliance.

The 500 MWe PFBR attained first criticality on April 6, 2026, signalling the start of a controlled, self-sustaining nuclear fission reaction—an essential phase before full-scale power generation. The milestone was achieved after clearance from the Atomic Energy Regulatory Board following rigorous safety evaluations.

Developed by the Indira Gandhi Centre for Atomic Research and constructed by Bharatiya Nabhikiya Vidyut Nigam Limited under the Department of Atomic Energy, the PFBR represents a cornerstone of India’s long-term nuclear strategy.

Unlike conventional reactors, the PFBR uses Uranium-Plutonium Mixed Oxide (MOX) fuel and is designed to generate more fuel than it consumes. By converting Uranium-238 into Plutonium-239, the reactor significantly enhances fuel efficiency. It is also engineered to eventually utilise Thorium-232, which can be transformed into Uranium-233—key to India’s future thorium-based energy programme.

Experts note that fast breeder technology acts as a bridge between existing pressurised heavy water reactors and next-generation thorium reactors. The system’s closed fuel cycle enables recycling of nuclear material, reducing waste and improving sustainability.

The successful commissioning underscores India’s growing capabilities in advanced nuclear technology, reinforcing long-term energy security and clean power ambitions.