Eskom has delayed the start of the Koeberg Nuclear Power Station's maintenance outage to next week Saturday to allow the strained national power grid to stabilise and recover some generation capacity.
This after the power utility implemented Stage 6 power cuts until Friday morning - leaving some neighbourhoods without any power for up to four hours per rotation.
Eskom Acting Chief Nuclear Officer, Sadika Touffie, said the decision to delay the refuelling and maintenance outage is necessary.
"While Eskom is ready to commence with the outage, with the contractors and all the requisite resources on standby, grid stability is an important consideration prior to shutting down the Unit 1 reactor to commence the maintenance and refuelling outage.
"This is going to be a long but necessary outage - the first of its kind for Koeberg. Eskom has taken care to ensure no undue delays are experienced once the project gets under way," Touffie said.
Eskom warned that outage of the unit will create some pressure on the grid as it is the power utility's biggest and most reliable unit.
"The [Unit one] outage will be for a duration of approximately six months. The extended unavailability of the unit is due to the planned long outages which does mean the electricity supply system may be under additional strain during the outage.
"Koeberg Nuclear Power Station is an important part of the Eskom generating fleet due to its reliable operation, low primary energy costs, its strategic location in the Western Cape to stabilise the national electricity grid and the fact that it is a clean source of energy.
"The Koeberg units, at 920MW each, are the largest generating units on the African continent. Their safe and reliable operation is a significant contributor to meeting the country's electricity demand. The Koeberg outages are planned at times of the year when the impact on the overall electricity supply is minimised as far as possible," the power utility said.
Eskom said that the outage for the power station is unavoidable and critical to ensure that it continues to run safely.
"Unlike other types of power stations, where fuel can be added to continue generating power, the fuel at a nuclear power station is sealed inside a reactor vessel, which is opened for refuelling every 15 to 18 months. This is also a time when the station will perform certain required inspections on equipment and perform more intrusive maintenance that cannot be performed when the unit is online.
"The rigorous maintenance, inspection and testing programmes are some of the critical activities that ensures that the plant remains safe and able to deliver this reliable level of performance," Eskom said.