"We have given permission for NPCIL to increase the power generation levels at its first unit in Kudankulam beyond 50 percent and up to 75 percent," S.S. Bajaj, Atomic Energy Regulatory Board (AERB) chairman, told IANS over phone from Mumbai.
Bajaj said the unit will have to conduct tests. Based on the test reports, further increase of power generation would be permitted.
"If all test results are satisfactory, then we may give permission to increase power generation levels up to 100 percent," Bajaj added.
The NPCIL is setting up two 1,000 MW Russian reactors at Kudankulam in Tirunelveli district, 650 km from here. The total outlay for the Kudankulam Nuclear Power Project (KNPP) is over Rs.17,000 crore.
KNPP is India's first pressurised water reactor belonging to the light water reactor category.
The first unit attained criticality in July 2013, which is the beginning of the fission process.
In August 2013, AERB permitted NPCIL to operate the reactor up to 50 percent level.
As the first unit at KNPP is yet to be declared as commercially operational, the power generated is termed as infirm power and supplied to the home state - Tamil Nadu - at low rates.
"Currently, the power is supplied to Tamil Nadu power utility at just over Re.1 per unit," said a source not wanting to be identified.
KNPP is India's first pressurised water reactor.
Only when the unit is declared as commercially operational, NPCIL can charge higher rate. The NPCIL is expected to realise a commercial tariff of around Rs.2.60 per unit.
"Now the Tamil Nadu state is enjoying the benefits of cheap Kudankulam power. Once the unit is declared commercially operational, then it would start supplying power to other southern states as well," the source said.
A senior NPCIL official told IANS last week that the focus is on increasing the reactor's power levels to 75 percent and stabilise the operations.
The NPCIL on its web site has declared that the first unit at KNPP would become commercially operational next month.
It is reliably learnt KNPP is likely to touch 75 percent generation levels sometime next week.
KNPP site director R.S. Sundar was not available for comments despite several attempts by IANS.