The Badarpur thermal power plant, Pragati power plant and Rajghat power plant tripped on Saturday afternoon, causing outages in several areas across the city.
Shutdowns were reported from some areas in the evening too.
Some of the affected areas include Mayur Vihar, ITO and Patparganj.
A 210MW unit at Badarpur plant, Pragati plant's 165MW unit and Rajghat's 50MW unit tripped due to technical problems, said a source.
The tripping occurred in the afternoon, as a result of which there was no electricity for about one hour.
Sidhartha Borgohain, a resident of Mayur Vihar Phase-1 in east Delhi, said that there was no electricity between 12pm and 1pm. "There was not much discomfort as it is cold, but such an outage has happened after a very long time in this area," he said.