Parts of Richards Bay was left without electricity after a fire broke out at the Hercules substation on Thursday morning.
A transformer burst into flames, affecting the power supply in the city and surrounds.
Spokesperson for uMhlathuze Municipality, Mdu Ncalane says the cause of the blaze is unknown at this stage.
He says technicians have since been able to switch power back on in the CBD to allow economic activity to continue.
Residential areas will be affected for some time as electrical technicians restore normal service.
“They are switching on back the CBD because it’s got some economic activity, hospitals and all the activities which are critical.
“Later on today, the residents will be switched back on using the Eskom Stage 2 load shedding.
“We are aware that Eskom is now on schedule Stage 1, but due to this issue, we are using the Stage 2 load shedding schedule until all customers are back on probably later today,” says Ncalane.