City Power says it's working around the clock to restore power at the Orlando switching station, following extensive fire damage to the local feeder board.

The Orlando 88kv lines were isolated due to a fault that caused the fire on the Soweto local feeder board in the early hours of Thursday morning, spokesperson Isaac Mangena said.

"Initial investigations suggest that this was due to acts of theft and vandalism where the batteries and links were stolen at the station, resulting in feeder jumpers being destroyed and taking the whole station down," Mangena added.

He said a team was dispatched to assess the extent of the damage, repair the infrastructure and replace the stolen batteries.

"Unfortunately, this outage has also disrupted Rand Water Board operations in Eikenhof as there is no power supply to our substation. City Power said the Orlando 88kv lines had been isolated due to a fault that caused a fire on the Soweto local feeder board in the early hours of Thursday morning. Supplied City Power

"The damage is extensive; however, we are working on restoring power," Mangena said.

The outage affected major substations, including those in Nirvana, Eikenhof, Nancefield, Pennyville, Eldorado Park and Soweto.

"We would like to reiterate that this is not load shedding. We apologise again for the inconvenience caused, and we will update customers on progress in later updates."