The second 220 MW unit at the Narora Atomic Power Station (NAPS) in Uttar Pradesh on Tuesday completed 731 days of continuous safe operation, India's atomic power plant operator NPCIL said on Tuesday.

The second unit at NAPS has become the fourth Indian reactor to achieve this milestone after Kaiga Generating Station Unit 1 (962 days), Rajasthan Atomic Power Station (RAPS) Unit 3 (777 days) and Unit 5 (765 days), the Nuclear Power Corporation of India Ltd (NPCIL) said.

The 220 MW unit at NAPS was an indigenous, pressurised heavy water reactor (PHWR) which commenced operation on July 1, 1992.

According to NPCIL, Indian reactors have demonstrated continuous operation exceeding a year for 34 times so far.

The nuclear power company operates 22 reactors with a total capacity of 6,780 MW.

Recently India's own and first 700 MW PHWR at the Kakrapar Atomic Power Project (KAPP) in Gujarat achieved its first criticality or controlled self-sustaining nuclear fission chain reaction.

Seven more reactors with a total capacity of 5,500 MW are under construction and work has been initiated on 12 more reactors with a capacity of 9,000 MW for which administrative sanction and financial sanction has been approved by the Central government.