"Sustained fission reaction and a series of steps will be going on in the second unit. Every step will be monitored and clearance will be obtained from The Atomic Energy Regulatory Board for going on to the next process," he told reporters here.
The second unit of KKNPP attained criticality at 8.56 pm, Mr Sharma said.
The first approach to attain criticality at the second unit began on July 8.
The second unit would attain the maximum capacity of 100 per cent power generation within three months and its synchronisation would be achieved within a month, he said.
Initially, the second unit would produce 300 MW. Tamil Nadu's share of power generated by Unit-II would be 562 MW, he said.
The first unit, which began generating power in October 2013, has so far produced 1006 crore MW.
Excavation works on the third and fourth units are going on at the site, he said, adding, in 2023-24, the NPCIL's total power production would be 30,000 MW.
The second reactor is the NPCIL's 22nd unit. Unit 1 and 2 of the KKNPP VVER reactors are being built with Russian collaboration. Each reactor has the capacity to generate 1000 MW of electricity.
Meanwhile, People's Movement Against Nuclear Energy (PMANE) coordinator S P Udayakumar said in a release at Coimbatore that they would stage a demonstration at Palyamkottai on July 16 against the criticality process being set in motion at the second unit.
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