CHENNAI: India's indigenous 500 MW Prototype Fast Breeder Reactor (PFBR) at Kalpakkam is set to begin phased power injection into the grid from December 2026 onwards, with nuclear operator Bharatiya Nabhikiya Vidyut Nigam Ltd (BHAVINI) pressing for urgent operationalisation of two key transmission lines to support commissioning activities and ensure nuclear safety compliance.
The development emerged during the 238th meeting of the Operation Coordination Committee (OCC) held on May 11, the minutes of which were uploaded on May 25.
According to the minutes, Bharatiya Nabhikiya Vidyut Nigam Ltd, a PSU under the Department of Atomic Energy, informed the forum that the PFBR had already achieved criticality and was undergoing stage-wise commissioning activities. It said phased injection into the grid was planned from December onwards as part of the reactor commissioning schedule.
BHAVINI sought immediate charging of the 230 kV BHAVINI-Kancheepuram Line-I and Line-II from the Kancheepuram substation end, stating that a reliable and redundant off-site power supply was mandatory under technical specifications governing nuclear power plants.
While both transmission lines were already in an ideal charged condition from the BHAVINI end, they were not in service from the Kancheepuram substation side.
BHAVINI said this was preventing the establishment of the required redundant grid connectivity, which was crucial for nuclear safety compliance and uninterrupted commissioning operations.
The Tamil Nadu State Load Despatch Centre (TN SLDC) informed the forum that charging of the lines was delayed due to certain commercial issues and that clarification from the Central Electricity Regulatory Commission wing of Tamil Nadu Power Distribution Corporation Ltd (TNPDCL) was awaited. It also stated that the commercial operation date (CoD) of BHAVINI has not yet been declared.
Member Secretary, Southern Regional Power Committee (SRPC), however, observed that commercial issues should not be linked with operational requirements and stressed that the PFBR project carried national importance.
BHAVINI told the forum that all transmission-related dues to Power Grid Corporation of India Ltd (PGCIL) had been regularly paid in accordance with the Appellate Tribunal for Electricity and CERC provisions. It added that while bay charges were earlier shared equally between TANTRANSCO and BHAVINI between 2014 and 2019, the entire cost had been borne by BHAVINI since 2019.
The PGCIL clarified that the transmission cost was currently being borne fully by BHAVINI and would later come under the Point of Connection (PoC) mechanism after declaration of CoD. It also stated that no transmission liability would devolve upon Tamil Nadu after commissioning of the Kancheepuram substation.
The forum advised BHAVINI to approach the Southern Regional Load Despatch Centre (SRLDC) by November 2026 with detailed power injection schedules and patterns for obtaining concurrence for infirm injection into the Inter-State Transmission System through the Tamil Nadu grid.
The OCC concluded that the issues related to charging the two transmission lines should be resolved as a priority and noted that TN SLDC could consider issuing conditional operational approval in view of the project's national importance.
BHAVINI sought immediate charging of the 230 kV BHAVINI-Kancheepuram Line-I and Line-II from the Kancheepuram substation end
While both lines were already in ideal charged condition from the BHAVINI end, they were not in service from Kanchi substation end
The State attributed the delay in charging of lines to commercial issues and arrival of clarification from CERC
The PFBR being developed at Kalpakkam is the first-of-its-kind nuclear reactor to use plutonium-based mixed oxide as fuel and liquid sodium as coolant
It will also utilise the spent fuel of Pressurised Heavy Water Reactors, which form the mainstay of nuclear power in India at present
While the state-run Nuclear Power Corporation of India Limited (NPCIL) operates nuclear power plants in the country, the PFBR at Kalpakkam is being developed by the BHAVINI