The fourth unit of the Kakrapar Atomic Power Project (KAPP-4) in Gujarat, with 700 MWe capacity achieved criticality on 17 December, 2023. Kakrapar is situated about 80 km from Surat.
The 700 MWe units are the largest indigenous nuclear power reactors to be built by the Nuclear Power Corporation of India (NPCIL). KAPP Unit-4 is the second in the series of 16 indigenous pressurized heavy water reactors (PHWR) of 700 MW each being set up in the country.
These PHWRs use natural uranium as fuel and heavy water as coolant and moderator. The Kakrapar Atomic Power Station already has two operating PHWRs with a capacity of 220 MWe each, called KAPS-1 and -2.
The indigenously built 700 MWe reactors have advanced safety features, including a steel-lining from the floor to the wall and a passive decay heat removal system to cool the fuel core. The 700-MWe unit-3 of KAPP started generating commercial electricity from 30 August, 2023. The reactor’s first criticality was ascertained after it met all the conditions set out by the Atomic Energy Regulatory Board (AERB).
The NPCIL operates 23 nuclear electricity reactors with a total capacity of 7,480 MWe. It has nine units, including KAPP-4, under construction, whereas 10 more reactors, with a total capacity of 7,000 MWe, are in the pre-project phase.
