Eskom confirms stage eight load-shedding ‘a possibility’
Eskom said on Wednesday that moving to stage eight load-shedding was “a possibility”, but was also unlikely.
The embattled power utility announced increased rotational blackouts from stage four to six on Wednesday, after relatively low stages prior to the cold snap that engulfed the country this week.
Stage eight load-shedding could mean up to 12-hours a day without electricity.
Responding to questions from the Mail & Guardian, Eskom said that stage eight remained a possibility this winter because it was currently unable to refill its emergency reserves.
In a statement on Wednesday, Eskom interim spokesperson Daphne Mokwena said storage reservoirs had not been filled, adding to pressure on the grid.
Eskom usually replenished its reservoirs over weekends when demand for electricity had decreased, but because of the cold front, it was unable to do so this past weekend. The power utility has three such power stations, two in KwaZulu-Natal and one in the Western Cape.
Eskom stores potential energy in upper reservoirs, which is released and converted into electricity when needed, according to Eskom’s fact sheet. To replenish water in the upper reservoirs, a large amount of electricity is needed.
Eskom said that during warmer periods, stages three to four load-shedding can be expected, while colder periods may increase this. “Should a cold spell coincide with multiple generator breakdowns, high stages of load-shedding may be necessary for a short duration.”
The cold front spreading across the country means the rosy winter South Africans were experiencing in terms of fewer power cuts had come to an end this week. The utility had suspended daytime load-shedding up until this week.
This is despite Electricity Minister Kgosientsho Ramokgopa’s promise on Sunday during a media briefing that the utility was prepared for the cold front that was approaching.
“The resolution of the load-shedding issue is principally on your generation side. Even if demand were to surge to the worst-case scenario, if these machines were performing at the rate at which we were expecting them to, we shouldn’t have a problem. Even if it [demand] gets to 34 000 megawatts or 36 000 megawatts, we shouldn’t have a problem,” he said.
Mokwena said load-shedding would move from stage four at 7am on Wednesday, to stage six from 2pm and last until 5am on Thursday. “This pattern will be repeated daily until further notice.”
Eskom’s initial plan was for stage four from Wednesday afternoon but, after reduced generation capacity as well as the high demand for electricity (about 33 000 megawatts), the extensive use of open-cycle gas turbines and pumped storage generation from the reservoirs was necessary over the past 36-hours.
“This necessitated stage six load-shedding,” Mokwena said.
On Tuesday, Mokwena said that over the past 24 hours, three generating units — one at three power stations, Arnot, Matla and Medupi — were returned to service. But others were taken out of service.
“In the same period, a generating unit at Matla and two generating units at Kriel power stations were taken out of service due to breakdowns,” she said.
She added that the delay in returning to service a generating unit at Kendal and two generating units at Tutuka power stations were contributing to the current capacity constraints.