Perfect storm sends SA to stage 6
● Eskom has blamed its descent into stage 6 load-shedding on a perfect storm of nonperforming renewables, critically low levels of pumped water used to generate hydroelectric power in peak hours, and units failing at various power stations.
The power utility was yesterday running unplanned outages at 15,958MW of generating capacity, while the capacity out of service for planned maintenance was at 6,771MW.
Electricity minister Kgosientsho Ramokgopa and senior Eskom executives will hold a press conference this morning to brief South Africans on urgent plans to de-escalate the load-shedding crisis.
The move to stage 6 at midnight on Friday came just more than a day after President Cyril Ramaphosa told South Africans in his state of the nation address “the worst is behind us and the end of load-shedding is finally in reach”.
Eskom spokesperson Daphne Mokwena told the Sunday Times yesterday: “Eskom power station general managers and their teams will continue to work diligently to ensure that the 2,473MW of generating capacity is returned to service by Monday, as planned.”
Many Johannesburg suburbs were subjected to two sessions of four-hour cuts within a 12 hours yesterday, raising concerns among residents that the prolonged hours of blackouts would lead to increased crime.
Mokwena said non-performing renewables were to blame for Thursday’s escalation to stage 4.
“On Thursday we had less output from renewables than we expected and we had to use our pumped storage,” she said.
“The pumped storage has an upper and lower dam. During the day, we use the upper dam and run water through a turbine to generate electricity. The water collects in the lower dam. During the night when demand for electricity is lower, we use the same turbine to pump the water back to the upper dam. We try to have full dams in the morning, ready for the demand pickup.
“Due to the need to replenish the pumped storage dams, which are required to meet the morning and evening peak loads, and a generating unit that was taken offline for repairs, we went to stage 4 on Thursday,” Mokwena said.
“We had three units — at Kusile, Kriel and Camden — return to service in the past 24 hours. Unfortunately, we lost a unit each at Lethabo and Kusile at the same time.”
She said the returning units could not make up for the lost generation from the bigger units that went offline, leading to an escalation to stage 6.
Energy expert Clyde Mallinson likened the national grid to “a rugby team bravely playing on in spite of receiving two red cards”.
“The remaining 13 players are working hard but they are outnumbered and something will have to give.
“What I see now to my dismay are too many coal-fired units having to pick up unfair extra duty. In the long run, this will hurt us.”
Mallinson said Eskom’s pumped storage was critical to its operations.
André Snyman of eblockwatch said criminals were increasingly taking advantage of load-shedding.
“Should a neighbourhood have long sessions of load-shedding, like eight hours in a 12-hour period, apart from the obvious of street lights being out, backup batteries for electric fences, alarms and CCTV cameras will start running down and stop working. The criminals know this and target these sessions.”