Transmission line trips, lakhs affected
Power: shock and sock
OUR BUREAU

A section of Lalbazar in darkness after the outage on Thursday evening. Picture by Sanjoy Chattopadhyaya
Calcutta, July 1: A CESC transmission line tripped this evening, enveloping large swathes of Calcutta in darkness or semi-darkness for 45 minutes to four hours and hitting even the Metro, Writers’ Buildings, Lalbazar and government hospitals for a while.

Some 12 lakh households and commercial establishments suffered power cuts whose geographical distribution was haphazard, dividing the affected neighbourhoods into small pockets of power haves and have-nots.

A combination of lucky factors, though, saved the private power utility from major embarrassment after a 132kV transmission line from the Budge Budge generating station to the Chakmir distribution centre in Maheshtala tripped around 5.50pm.

One, the pleasant weather — the maximum temperature was 33.1 degrees Celsius and it was cooler in the evening — mitigated people’s suffering.

Two, no soccer World Cup match was scheduled today. Else, even though the brunt of the power cut would have preceded the 7.30pm kick-off, it could have triggered panic, public fury and perhaps even street blockades.

Three, an uninterrupted import of over 300MW from the West Bengal State Electricity Distribution Company Ltd helped keep the shortfall to 700MW. “Without the import, the deficit would have crossed 1,000MW and almost every part of the city would have been without power,” a CESC official said.

That power returned to most of the affected state-run hospitals after about 30 minutes was lucky too. “The ventilators had back-up power for 45 minutes and if power supply were not restored within that time, it could have been a serious problem,” said Debashish Bhattacharya, medical superintendent of SSKM Hospital, where the power cut lasted from 6.40pm to 7.10pm. Private hospitals and nursing homes mostly had their own power back-up.

Among the areas affected were parts of Shyambazar, Sobhabazar, Girish Park, Lake Town, Kankurgachhi, Sealdah, Chandni Chowk, Bhowanipore, Hazra and Park Street.

The shortfall lasted well past 10pm since the units that had tripped were restored in phases. “The situation will be normal before midnight,” a CESC official said.

The state secretariat was left powerless for over 43 minutes. Chief minister Buddhadeb Bhattacharjee escaped the Writers’ blackout, having left office at about 5.55pm, only to walk into a dark CPM party office on Alimuddin Street about 10 minutes later.

Finance minister Asim Dasgupta and law minister Rabilal Moitra were forced to use the stairs instead of the VIP lift at Writers’, while labour minister Anadi Sahu held a meeting in his chamber using an emergency light.

The CESC official confirmed that more than half the power utility’s 23 lakh consumers had suffered. “It (the tripping) had a cascading effect and all the generation units except the two at our Budge Budge plant collapsed temporarily,” he said.

Two units at the Titagarh generating station (240MW), one unit each at Southern (135MW) and New Cossipore (130MW) and one of the three units at Budge Budge (110MW) went offline.

Late at night, CESC engineers were still to pinpoint the problem.

A senior power department official blamed the overhead transmission and distribution system. “Such freak accidents can be minimised if the lines are underground,” he said.