Homes in Alfred Cove, Applecross, Ardross, Brentwood, Melville and Mt Pleasant were all affected by the blackout, which was caused by a fault on an underground electricity cable.
A Western Power spokesman said the fault occurred around 6.10pm on Tuesday, May 31.
Power was restored to most customers by 8pm.
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READ NOWThe spokesman said the outage was not a result of planned work and the cause of the fault was yet to be determined.
“Western Power carries out an ongoing works program on the network to maintain safe and reliable electricity supply for our customers,” he said.
“We will always contact customers affected by planned maintenance in advance so they can arrange to minimise the impact of the outage on their individual circumstances.”
An Ardross resident, who asked not to be named, said the outage occurred just as he was sitting down to dinner.
“I phoned the Synergy number and got a recorded message saying they were aware of the outage and listing the affected suburbs but provided no other explanation,” he said.
“It’s not the first time this has happened – the whole area blacked out last year during a storm too.
“This time around it was a quiet night and you have to wonder why in a supposedly advanced country, and a fairly prosperous area, this kind of thing is happening.”