Orion believes a major power outage across Christchurch this week was caused by an isolated incident at a substation.
However, they still do not know what that might be.
The outage Wednesday night left about 30,000 customers in the north of the city without power for several hours. Orion initially believed the problem to be on the 9km line between the Papanui and Islington substations. However, extensive investigations with infrared cameras found no issues with it.
Orion energy projects manager Stephen Godfrey said the problem seemed to be solely with the Papanui substation, where some residents reported seeing a "flash" around the time of the power cut.
‘‘It’s not an obvious problem. There is no debris around the area but all indicators point to a problem at the substation.’’
Godfrey said there was still a process to figure out the problem, including switching off some power so the station could be looked at.
This would not affect power to customers, he said.
It was not clear when the mystery would be solved.
On Wednesday, power was quickly restored to 12,000 properties and for the remaining customers within three and a half hours.
Orion chief executive Rob Jamieson said the outage was rare.
‘‘Although very unfortunate ... hopefully this outage can serve as a reminder for everyone to have a backup plan for when power does go.’’
Residents took to social media to report the outages, with St Albans, Mairehau, Merivale, Papanui and Northwood among those affected.
Keryn Cottier said on Facebook that Christchurch was ‘‘an eerie ghost town’’.
‘‘Full blackout. No traffic lights, street lights, normal power. Eeep creepy.’’
Christchurch resident Troels Nielsen said the power cut was "bloody inconvenient".
‘‘I was in the middle of washing my clothes when the power went out. I'm travelling today and all my clothes are still wet.’’
- The Press
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