Chennai:
Two reactors of the Nuclear Power Corporation Ltd's (NPCIL) Madras Atomic Power Station (MAPS) that shut down after a power supply breaker tripped leading to a power cut early on Sunday would restart generation around Aug 23, said a senior official here on Monday.
"Around 1.15 am on Sunday, a breaker in 230 KV switchyard tripped resulting in power supply failure. The reactor's automatic shutdown process was triggered. Both reactors shut down their operations. Both units would come back to operation by Aug 22 or Aug 23," K Ramamurthy, station director, MAPS, told IANS.
According to him, four standby diesel generators got into operation immediately when the main power supply failed.
"There was no sudden surge in power generation or supply that resulted in the breaker to fail," Ramamurthy said.
He said that the breaker that failed is one of the old ones, all of which MAPS is replacing.
"We have 11 such breakers and have replaced six units. Each component costs about Rs.20 lakh," Ramamurthy said.
"The moment the power failure happened the turbines tripped. We came to know of the incident immediately as the sirens sounded out," Ramamurthy said.
Located in Kalpakkam around 70 km from here, MAPS has two reactors of 220 MW each, but they have been functioning below their rated capacity owing to paucity of fuel.
"The fuel supply situation is improving. The first unit was generating 180 MW and the second around 160 MW. By the end of this year we expect the power generation to touch full capacity at both the units," Ramamurthy said.
The shutting down of the two reactors did not affect the fast breeder test reactor (FBTR) and the mini reactor Kamini located at Indira Gandhi Centre for Atomic Research (IGCAR).
A breeder reactor is one that breeds more material for a nuclear fission reaction than it consumes. Power supply to IGCAR comes from MAPS.
"The FBTR was shut down on Friday as per our plans. So it was not operational when the MAPS units shutdown. Even if the test reactor was functioning it would have shut down automatically," G Srinivasan, director, reactor operation and maintenance group at IGCAR, told IANS.
According to him, the mini reactor was not in operation when the incident happened.
"The Kamini reactor is operated only when needed," he said.
The MAPS shutdown also did not affect the construction of the 500 MW prototype fast breeder reactor (PFBR) by Bharatiya Nabhikiya Vidyut Nigam Ltd. (Bhavini) at Kalpakkam.
"We have two sources for power, one from MAPS and the other from the grid. As the MAPS units shut down at night we were not affected. Now we are getting the grid power and work is on at the site," Prabhat Kumar, chairman and managing director at Bhavini told IANS.