Large parts of Gurgaon were thrown into darkness on Friday evening after a fault at a 220kV substation in Sector 72 triggered a major power outage across multiple areas, at a time when the city was already reeling under intense heatwave conditions.Temperatures had touched 42.7°C, while electricity demand had surged to an all-time high just a day earlier, putting additional strain on the already stressed power infrastructure.— ThengaChutneyy (@ThengaChutneyy) Rapid Metro services disrupted; commuters strandedThe blackout also severely impacted Rapid Metro operations, leaving several commuters stranded at stations and inside trains during peak hours.A Delhi Metro official told TOI, “The power supply failure from HVPNL’s Sector 72 substation, which feeds Rapid Metro and the Gurgaon section of the Yellow Line, halted Rapid Metro train services from 7.50 pm to 8.33 pm.”Some commuters were forced to step out of halted trains and walk along metro tracks to reach nearby stations, causing alarm and confusion during the disruption.Technical fault at Sector 72 substation triggered cascading outageAccording to officials, the disruption began around 7 pm after a transformer fault developed in one of the circuits at the Sector 72 substation. This led to a shutdown and cascading impact across multiple downstream substations.Supply was affected in several key areas including sectors 38, 44, 46, 52, 56, 15 and the Maruti plant, disrupting power across Golf Course Road, Sohna Road, MG Road and large parts of Sectors 45, 47, 50, 51, 52, 56 and 57.An official involved in restoration work said, “Our teams are working on the fault, but repairs may take several hours.”Residents suffer through sweltering heat and long power cutsFor thousands of residents, the timing of the outage made conditions especially unbearable amid extreme heat and humidity.“It’s impossible to sleep in this heat. The power has been out since evening and we have no idea when it will return,” TOI quoted Amit Sharma, a resident of Sector 46, as saying.In Sector 56, residents reported repeated tripping issues earlier in the week. “This complete blackout is the worst we’ve seen this summer,” said Ritu Arora.Even societies with backup generators faced challenges, with rising diesel costs adding financial pressure. “Generator backup is expensive. During long cuts, societies burn huge amounts of diesel and the bills go up,” said Sumit Anand of Sushant Lok.Heatwave intensifies pressure on Gurgaon power gridThe blackout came amid a severe heatwave gripping the region, with IMD issuing an orange alert for heatwave to severe heatwave conditions across Haryana between May 24 and 27.On Thursday, Gurgaon recorded its highest-ever power demand at 2,372 MW, reflecting the extreme strain on the electricity network as temperatures remained above 40°C throughout the week.Rapid Metro restoration and partial recovery of servicesOfficials confirmed that Rapid Metro services were suspended between 7.50 pm and 8.33 pm but were restored once power supply was stabilised through backup systems.A commuter told TOI, “I’ve been waiting for 30 minutes. Some people have already left to find other means of transport.”Repeated infrastructure failures raise concernsThis incident comes just days after another major outage caused by a fire at the Sector 9 substation, which left around 1,500 families without power for nearly nine hours in parts of New Gurgaon.Residents expressed frustration over recurring disruptions during peak summer demand.“Every summer it’s the same story, faults, fires and long cuts. The system clearly cannot handle the load,” said Naveen Batra of Sector 52, speaking to TOI.