MUMBAI: The island city, from Colaba to Mahim, and parts of the suburbs suffered a power outage for up to one and a half hours on Sunday morning.
It was blamed on a transmission grid failure—a “fire in the jungle” near BARC led to shutdown of a 220KV line, according to an MSETCL official—bringing back memories of October 12, 2020 when power cuts in the city lasted for up to 12 hours.
The August Kranti Rajdhani Express arrived 30 minutes late at Mumbai Central. Scores of WR commuters were stuck in suburban trains which came to a standstill between Churchgate and Andheri for nearly an hour. WR announced the cancellation of 75 local trains while 130 were delayed. On CR, trains came to a halt for a few minutes across the CSMT-Kalyan line and the Harbour corridor as motormen witnessed power fluctuation in overhead wires. Residents of several high-rises in the island city were stranded in their homes or had to wait it out on the ground as most lifts stopped.
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The shutdown of Kalva-Trombay transmission line at 9.49 am following a “fire in the jungle” near BARC led to an overload on the Tata Power Trombay Salsette-1 line, which witnessed "massive voltage fluctuations" causing tripping. The cascading effect led to power outages in south and central Mumbai, and also in Bandra, Khar, Chembur and Kurla, among other places. BEST’s supply was majorly hit as it receives power entirely from Tata while sections of Tata and Adani Electricity consumers were also affected.
What about the city’s islanding system, which is supposed to kick in during a power incident? Tata Power president Sanjay Banga said 'islanding' occurs when the entire city faces outage and is cut off from the rest of MMR and the state. “In this case, it was just a part of the city that was affected. Besides, the root cause was the shutdown of all four transmission lines of MSETCL which supply power to our Trombay receiving stations. Two circuits were already under maintenance; the third circuit tripped at 8.40 am, and the last circuit at 9.50 am."
Banga said, "When it tripped, it created a disturbance in the Tata Power system. There was a reduction in demand to the tune of 850 MW. The total demand of Mumbai came down from 2,000 MW to around 1,200 MW and different parts of Mumbai were affected." Tata Power expedited restoration, with its hydro plants being intact. “The Bhira hydro plant got islanded and synchronised. This helped in expediting first for essential services and gradually for residential and commercial areas,” a Tata Power official said. An Adani spokesperson said their consumers were largely unaffected as the power firm was able to ramp up generation at Dahanu. BEST general manager Lokesh Chandra said restoration was in phases.
State energy minister Nitin Raut has ordered a probe. “After the power outage, I spoke to officials in the state government and also Tata Power authorities. I told them that the priority was to restore power. Indeed, power was restored within 70 minutes,” he said. On Sunday night, there was a power cut at Antop Hill due to feeder fault. BEST officials said it was a local fault and supply was to be restored soon.
