PFBR Criticality - Stage II Milestone
On 6 April 2026 India's long-awaited 500 MWe Prototype Fast Breeder Reactor (PFBR) at Kalpakkam in Tamil Nadu reached first criticality, the moment a reactor first holds a controlled, self-sustaining fission chain reaction. Designed by IGCAR and built by the public-sector BHAVINI, the sodium-cooled machine formally carries the country into Stage II of its three-stage nuclear power programme, the stage meant to multiply India's usable fissile stock and open the path to tapping its vast thorium reserves in Stage III.
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