A combination of overheated equipment, an oil spill, and a blast caused a major power grid failure in Gurgaon on Friday evening, plunging large parts of the city into darkness and disrupting Rapid Metro services. The incident occurred at the critical Sector 72 substation of Haryana Vidyut Prasaran Nigam (HVPN) around 7 pm.
Sequence of Events
According to officials, a technical fault hit two circuits at the Sector 72 substation, which draws power from a 440 kV line and supplies two 220 kV substations. The fault led to oil leakage from a current transformer, which caught fire and exploded before the breaker could trip. With the temperature at 42.7 degrees Celsius and power demand having reached a record 2,372 MW a day earlier, the grid was under severe strain.
An official stated, "In a matter of minutes, overheated equipment failed and flames tore through critical infrastructure. Homes and offices plunged into darkness and commuters on the Rapid Metro were left stranded in the heat."
Cascading Failure
The blast not only damaged the transformer but also nearby poles and associated equipment, triggering a cascading failure across the system. "The flames spread quickly and damaged the network of circuits and current transformers, causing a complete breakdown," the official added.
The disruption immediately affected supply to 220 kV substations in sectors 52 and 56, and 66 kV substations in sectors 15, 38, 44, and 46, as well as the Maruti plant area. Large stretches of Golf Course Road, Sohna Road, MG Road, Palam Vihar, and parts of sectors 15, 38, 44, 45, 46, 47, 50, 51, 52, 56, and 57 were impacted.
Impact on Rapid Metro
Rapid Metro services were halted between 7.50 pm and 8.30 pm because the system depends on a single-source supply from the Sector 56 substation. In contrast, the Delhi Metro's Yellow Line continued to run as it draws power from both Delhi and Haryana.
HVPN executive engineer Anil Malik said, "By 8.30 pm, one circuit was restored, allowing Rapid Metro to resume operations. It was our top priority."
Restoration Efforts
Teams from HVPN and Dakshin Haryana Bijli Vitran Nigam (DHBVN) worked through the night to isolate the fault, reroute load, and revive supply in phases. The entire substation system was normalized by 10.22 pm, full supply was restored soon after, and the damaged current transformer was replaced by midnight.
In circle 1 areas, about 95% supply from the Sector 15 and Mehrauli Road substations was back by 10.30 pm, with the remaining feeders restored by 1 am. In circle 2, sectors 38, 44, 46, 52, 56, and the Maruti area regained supply by 11.30 pm.
Residents' Ordeal
For residents, the outage was punishing. Amit Sharma (38), a resident of Sector 46, said, "It's impossible to sleep in this heat." In Sector 56, Ritu Arora noted that repeated tripping had already damaged appliances. Sumit Anand (41) of Sushant Lok added that even backup came at a cost because societies had to burn expensive diesel.
Renewed Concerns
The blackout occurred just two days after a fire at the Sector 9 substation caused a nearly nine-hour outage in parts of the city, renewing concerns over how vulnerable Gurgaon's power network has become during extreme summer load.
The incident highlights the urgent need for infrastructure upgrades and preventive measures to ensure grid stability in the face of rising temperatures and power demand.
