India Achieves First Criticality of 500 MWe PFBR at Kalpakkam

India has achieved a major milestone in its civil nuclear programme with the indigenous 500 MWe prototype fast breeder reactor (PFBR) at Kalpakkam reaching first criticality on 06 April, 2026.

This development marks a significant step forward in the country’s three-stage nuclear power programme and strengthens its long-term vision for energy security and self-reliance through advanced indigenous technologies. The achievement represents a key technological breakthrough in fast breeder reactor development, reinforcing India’s capability to expand its nuclear energy capacity using domestically developed systems and expertise. State-owned engineering company Bharat Heavy Electricals (BHEL) played a crucial role in the project’s execution. On the reactor side, BHEL was responsible for the manufacturing, supply and fabrication of the inner vessel and thermal baffle, along with technology development for critical components such as the steam generator-evaporator and main vessel.

On the secondary side, it supplied and erected the 500 MWe main plant turbine generator package using indigenous technology. These contributions highlight BHEL’s engineering capabilities in complex nuclear infrastructure projects. The PFBR milestone is expected to pave the way for further advancements in fast reactor technology and strengthen India’s position in advanced nuclear energy development.