More than 30,000 people were without power for several hours after an outage hit Sydney's north-west on Friday afternoon.
Residents in the area reported hearing a bang at around 4.45pm as the power went out, with some people walking into the street to see what had happened.
The widespread outage covered homes and businesses in the suburbs of Eastwood, West Ryde, Ryde, Rhodes, Meadowbank, Putney, Denistone, Melrose Park, Epping and Denistone East.
Emergency power crews were called to the scene and found the outage was caused by a fault at Meadowbank substation.
They sourced the problem to a damaged porcelain insulator at the substation, where repairs will continue on Friday night.
Power returned to all affected homes and businesses at around 7.10pm, ahead of estimates of 9pm.
Ausgrid spokesman Anthony O'Brien said the damage was quite minor and crews were able to restore power from another part of the network.
He apologised to residents in the area for the disruption.
Residents reported an hearing an explosion and seeing smoke from the substation, with pieces of debris falling into the street.
Power restored to all homes & business around #Eastwood, #Ryde after fault inside #Meadowbank substation. Sorry for the inconveniece today— Ausgrid (@Ausgrid) November 25, 2016
Mr O'Brien said this was related to the fault, which would have unfolded with a bright flash, a loud noise and some smoke.
"We know that there were reports of an explosion on site," Mr O'Brien said. "What's likely to have occurred is when there's a fault on the network of this nature, the network can shut down.
"The act of that happening can cause a bang, and large amounts of heat generating from electricity can also generate smoke."
He said there was "no evidence of damage from an explosive event".
"They've heard a very loud bang, they've probably seen smoke coming from that substation, but there's no evidence of damage from an explosive event. There's no large fire," he said.
A car accident at Ryde which reportedly brought down power lines did not contribute to the outage.
Numerous sets of traffic lights were blacked out on main and local roads in the area, with the Transport Management Centre advising 42 sets of lights were out of operation.
Some of the lights were on busy intersections, including Victoria Road. All motorists were advised to "take extra care" as the evening peak began.
"Traffic through these suburbs is heavy so motorists are advised to avoid these areas or allow plenty of extra travel time and follow the directions of police on site," a Transport Management Centre spokeswoman said.
Heavy traffic was complicated by a four-car accident in nearby Concord West, where one person remained trapped at around 5.30pm.
There were no reports of blackouts in Concord West at the time of the accident. Southbound traffic was affected near Victoria Avenue.
The outage came as many began to leave work for the day, with reports of at least one person stuck in a lift at Meadowbank.
Employees of businesses in Rhodes were left to use emergency stairs to leave their buildings, while media organisation AAP was also impacted by the outage, with its distribution website brought offline.
As power returned, scores of people took to social media to express their relief - and detail plans to watch TV with a cold drink.
