"At 2305 hrs (last night), the first nuclear reactor attained criticality(also known as atomic chain reaction) and all the parametres are normal. Sustained nuclear chain reaction has been achieved. Everything is normal," R S Sundar, site director of the Kudankulam Nuclear Power Plant (KNPP) told PTI.
Overcoming a series of protests and legal hurdles that delayed the commissioning of the plant, the 1000 mw pressurised water Reactor (PWE) finally attained criticality, prompting the nuclear establishment to rejoice the "red letter day."
"Great achievement... It is a historic moment every Indian (has) to be proud of... A red-letter day indeed," said J Daniel Chellappa, Senior Scientist at Bhabha Atomic Research Centre (BARC), and Technical Coordinator, Central Expert Group on KKNPP.
The criticality milestone was achieved at 11.05 PM after the "Boron dilution process" allowed neutron concentration to go up and start nuclear fission, generating heat.
The reactor will start its initial production of 400 MW electricity within 20 days, Union Minister V Narayanasamy said.
"Yesterday, they started the criticality. Now the reaction of nuclear in the plant has started for the purpose of development of electricity. The production of electricity will be started in next 20 days," Narayanasamy told PTI over phone from his constituency Puducherry.