The source, not wanting to be named, told IANS: "The first unit is expected to restart generation only in December. The second unit may take longer time to start power generation."
The NPCIL is building two 1,000 MW atomic power plants with Russian equipment at an outlay of over Rs.17,000 crore.
The first unit was connected to the southern grid in December 2014. The unit was operating at 60 percent capacity for some time before it was shut down for annual maintenance.
At the time of its shut down in June, NPCIL said the unit will restart after 60 days post annual maintenance and refuelling.
According to Power System Operation Corporation Ltd (PSOC), the KNPP first unit is expected to restart power generation on October 30. But this deadline is expected to be breached again.
Atomic Energy Commission chairman Sekhar Basu recently told IANS that as per current indications, the first KNPP unit is expected to restart later this year and the second unit would go on stream sometime next year.
He also said the restart of the first unit may happen this December.
Mr Basu said lot of checks have to be carried out as the first KNPP unit was shut down for the first time since it started generating power.
Despite the unit being first of its kind in the country and that it has been shut down regularly, the Atomic Energy Regulatory Board (AERB) this year issued a five year operating licence for the plant.
Normally AERB issues operating licence for a year if the plant is first of its kind in the country and based on the test reports the licence would be renewed, an NPCIL official told IANS earlier.
Despite several attempts by IANS, KNPP's site director RS Sundar was not available for clarifications.
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