Mumbaikars woke up to no electricity on Sunday owing to a massive power outage witnessed across Mumbai due to a grid failure that also affected the city's lifeline – the local train services – for some time. This is the first power breakdown since October 12, 2020, when there was a major power failure following grid disturbance. Complaints of power cuts poured in from South Mumbai, Chembur and Govandi.
Maharashtra energy minister Nitin Raut has ordered a high-level inquiry into the power outage. “I have taken this case very seriously and ordered a high-level inquiry. Appropriate action will be taken against those found guilty,” he said. Meanwhile, the Brihanmumbai Municipal Corporation (BMC) alerted.
Mumbaikars about the power outage. “Due to some technical issues, there has been a power supply failure in many parts of the city. Our team is in the field to resolve the issue.
The power supply is expected to be restored in an hour. We regret the inconvenience,” the BMC said in a tweet. The Maharashtra State Electricity Transmission Company (MahaTransco) said Sunday’s power failure took place after its 220 kV Kalwa-Trombay transmission line tripped at 9.49 am due to a fire below the line on the BARC campus. This led to overloading of the 220 kV Salsette-Trombay circuit 2.
“Due to tripping of Tata Power units 5 and 8, around 804 MW load was affected in south Mumbai, Chembur, the western suburbs and Dharavi area. Railway supply was affected from 9.50 am and normalcy was restored at 10.45 am. Complete normalcy of load was restored around 11.00 am,” it said. MahaTransco further stated that Tata Power units 5 & 8 tripped on under frequency and 220 kV Salsette-Trombay line 1 was out for Metro 4 work. Tata Power president (Transmission and Distribution) Sanjay Banga said, “Tripping of MahaTransco created a disturbance in our system. There are four circuits at MahaTransco 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. When it tripped, it created a disturbance in our system.’’ Banga said a detailed investigation was being conducted to ascertain the reason for the outage, adding that Tata Power is coordinating with all agencies, including the State Load Dispatch Centre, to find out the exact reason and see how such incidents can be avoided in the future.
Tata Power said its hydropower plants were intact and that the Bhira hydro plant got islanded and synchronised. According to Adani Electricity, “Adani Electricity consumers were largely unaffected by Sunday's outage as it was able to ramp up generation at Dahanu in a very short time which helped in early restoration of power supply to consumers in South Mumbai as well.’’
The Brihanmumbai Electric Supply & Transport (BEST) also released a similar statement saying the outage was caused due to tripping of MahaTransco’s 220 kV transmission line on Mulund-Trombay power supply network. It said most parts of Mumbai were affected but the power supply was later restored.