Affected areas included Hawea and Makarora, Beacon Point, Penrith Park and Wanaka North — in the Wanaka and Upper Clutha area — and Queensbury in Central Otago.
Aurora Energy operations and network performance general manager Matt Settle said there had been several unrelated faults that resulted in unplanned power outages at various times.
"We are doing work in the area to upgrade the electricity network and late last week one of the main power lines that supplies the area had a planned outage to keep our contractors safe while they were replacing power poles.
"Unfortunately, the second line tripped and the team responded as quickly as possible to get power back on for our customers."
The cause was tracked down to a defective insulator that had now been replaced.
Another outage happened earlier this week when electrical circuits were being reconfigured and the line tripped following a new insulator being installed, and on Wednesday night a fault with a transformer in Wanaka caused a power cut.
