An “unacceptably high” level of lost power-generating capacity, wet coal caused by unpredictably heavy rains and delays in the addition of renewable energy to the grid are among the reasons SA is facing a bleak week of load-shedding.

Implemented on Easter Sunday afternoon and escalated to stage four early on Tuesday, the rolling blackouts are set to continue until Friday morning in “a best-case scenario”, with stage six load-shedding “not envisioned for this week”.

This is the view of Eskom’s group executive for generation, Philip Dukashe, who made the announcement at a briefing on Tuesday at which an update was given on Eskom’s plight.

The power utility’s head of transmission, Segomoco Scheepers, elaborated on a “worst case scenario” for load-shedding during winter.

“We have done the assessment for winter and I think the big variable is the level of unplanned [outages]. We normally look at three scenarios and at the last briefing we did give an indication that if we are able to contain the unplanned [outages] below 12,500MW we should not have any load-shedding. Today, we are struggling to attain the lower level that we desire and it progressively increases to 37 days for winter and in the extreme could be as high as 101 days — but that is in the extreme.”

CEO Andre de Ruyter said this week’s load-shedding was the result of a disappointing performance by generation, and much was being done to improve the situation.

He said Eskom had lost 5,124MW, which was out on maintenance as part of efforts to restore reliability to the system; “unplanned” losses amounted to 11,164MW with a further 4,158MW on “partial losses”, bringing the total loss to 15,672MW.

This he said, was “unacceptably high” and had prompted stage 4 load-shedding to “prevent a total collapse of the system” which would take more than a week to restore if it happened.

“We are anticipating a demand of 29,988MW during the peak this evening and so we needed to make allowance for that,” De Ruyter said.

In terms of strategies that were being implemented to alleviate the crisis, he said diesel reserves in the tanks at Ankerlig power station should be “north of 80%” but were sitting at 67%.

“So we are expecting 129 trucks loaded with diesel to deliver there today,” he said.

He added that the floods in KwaZulu-Natal had led to a reduction in the province’s power demand from 1,600MW to little more than 900MW, which meant they were able to cushion the area during stage 2 load-shedding. But this was being revised after the escalation to stage 4.

Stage 4 requires that up to 4,000MW of the national load be shed — double the amount in stage 2. This equates to 12 outages of two-and-a-half hours over a four-day period or 12 four-hour outages in eight days. The Eskom load-shedding model allows for up to stage 8, equal to 12 hours a day with no power.

The current power crisis situation has come about after a record high number of “unplanned breakdowns” compounded by the tripping of units at Majuba and Tutuka — the country’s poorest performing power station.

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