Persistent rain and high demand for electricity over the long weekend caused a “significant” shortfall in generation capacity, Eskom said, after it scaled up its rolling blackouts from state two to stage four on Tuesday.
The state power utility had no alternative but to implement stage four load-shedding to shed about 4 000 megawatts of demand “for us to safely navigate through the current demand on the system to prevent a total collapse of the system”, chief executive André de Ruyter said during a media briefing.
Eskom has a total unplanned loss of 15 672MW, which De Ruyter said was unacceptably high.
Phillip Dukashe, the group chief executive of generation at Eskom, said scheduled maintenance that needed to be conducted over the weekend could not be completed because of the high electricity demand during the cold long weekend.
On Friday, the demand was about 700MW higher than forecast; on Saturday it increased to 1 687MW, lessening slightly on Sunday to 1 200MW.
Eskom said it hoped to be in a better position on Thursday evening or Friday morning, when it would reassess whether to suspend load-shedding before the weekend.
But Dukashe added: “That also depends on how well we can replenish our reserves … as we prepare for the start of next week [and] we would like to have all our diesel and all our pump storage in a healthy state.”
Dukashe dismissed the possibility of ramping up the rolling blackouts to stage six, saying Eskom expected some units to be operational again as of Wednesday and Thursday.
De Ruyter noted some improvements in reserves capacity at power stations such as Ankerlig and Ingula.
“At Ankerlig we are sitting at 67% of diesel in our tanks. Again, this is not ideal. We would like that number to be north of 80%. So we are expecting delivery of about 129 diesel trucks during the course of today. That will replenish those reserves,” the Eskom boss said.
Last week, De Ruyter said extreme flooding in KwaZulu-Natal had contributed to the current operational difficulties at the electricity utility, which could not carry out repairs while flooding was affecting stations such as Ingula.
“We have been able to improve the performance at Ingula. Ingula now only requires another 12 hours to be fully replenished and that will go a long way for us to safeguard that particular reserve,” De Ruyter said.
The Eskom executives said the utility had not suffered any serious damage to its infrastructure in KwaZulu-Natal, where extensive flooding has left more than 440 people dead and severely disrupted road routes and the Port of Durban. The power utility did concede that it was battling to receive enough fuel supply, but added that contingency plans were in place.
No load-shedding has been implemented in eThekwini metro, hard hit by the flood, because the area is not consuming its daily average of 1 600MW. But the implementation of stage four load-shedding might affect this, Dukashe said.
Eskom teams are working to support the eThekwini municipality to try to restore power supply to affected areas, the power utility said.
For the rest of the country, rotational blackouts will continue for the second consecutive week. Eskom last implemented stage four rotational power cuts in early March.