Johannesburg - There is a high probability of stage two load shedding from 10am to 10pm on Sunday, state-owned power utility Eskom said.

Due to the high unavailability of a plant on Saturday, Eskom had been unable to build the necessary reserves, "thereby resulting in a high probability of stage 2 rotational load shedding" from 10am until 10pm on Sunday, Eskom said in a statement.

"A generation plant continues to be out on planned maintenance (approximately 5000 MW) and there is a higher than expected number of units (currently at approximately 10,000 MW) on unplanned maintenance due to technical faults.

"Cahora Bassa hydropower plant is still supplying 700 MW less to the grid as a result of a damaged transmission line, which occurred late on Wednesday. Over and above these challenges, we are experiencing low diesel reserves due to the continued pressure on the national grid resulting in excessive usage of open-cycle gas turbines (OCGTs).

"In addition, the need to build emergency water and diesel resources to limit the load shedding possibility or magnitude thereof in the following week also remains. Our maintenance teams continue to work through the night to bring back units," Eskom said.

Customers should note that some municipalities may take longer to restore load. If customers experienced outages for longer periods than announced, they should contact their supplier (Eskom or the municipality) as this may be a localised power outage.

"Eskom would like to thank its customers for using electricity sparingly and industrial customers for their participation in load curtailment [on Saturday]. We will keep customers informed if there are any changes to the system. We sincerely apologise for the inconvenience to affected customers," Eskom said.

African News Agency/ANA