MUMBAI, May 23 -- Power outages left residents in parts of Dadar, Wadala and Dadar Parsi Colony, as well as in Gaondevi and Girgaon Chowpatty, without electricity at the height of summer on Friday night. For some of these areas, it was the second such outage in eight days. Power supply was interrupted in Dadar and Wadala at 9.25 pm due to a fault at the BEST undertaking's Kings Way receiving station in Dadar. "Electricity supply was interrupted due to an air trip in transformer numbers 2 and 3 of the receiving station," said a BEST official. He said it would take around four hours to restore supply. A separate power outage was reported in Gaondevi and Girgaon Chowpatty, when a transformer caught fire at the BEST's Girgaon Chowpatty installation. "The fire was in a transformer of the high voltage distribution board," said the BEST in a statement, which added that it would take around an hour to be restored. On Thursday night, Antop Hill and Wadala residents faced an outage that lasted several hours. Earlier, on May 14, around 3,000 BEST consumers in Dadar, Sitladevi and Matunga Road faced prolonged power outages owing to a cable fault at the Sitladevi receiving substation. In the last year, the BEST received around 7,500 power outage grievances, with about 2,500 faults remaining unresolved. There has been a 15% surge in complaints, year on year....