Sudden load shedding due in part to Cahora Bassa loss
On Wednesday evening, South Africa was hit with Stage 2 load shedding without prior warning as Eskom suffered the loss of five generating units.
Two of the units were from the Cahora Bassa hydro dam in Mozambique.
In a statement on Thursday, the utility said that the power system was “constrained but stable” going into the peak evening period, and that it had sufficient emergency reserves.
However, the loss of the units before and during the period triggered load shedding for ten and a half hours overnight, starting at around 18:25.
By Thursday morning, four of the five offline units were restored, along with two additional units from previous outages. In all, 3 000MW of power was restored.
Over the long weekend, an additional 2 120MW is expected to return to service, contributing to grid stability, Eskom said.
“The previous load shedding events this year were primarily as a result of insufficient emergency reserves that needed to be replenished following extended delays in returning units to service after maintenance, that was not the case last night,” said Dan Marokane, Eskom Group Chief Executive.
“With the currently constrained system and the planned use of emergency reserves to manage peak periods, the loss of five units prior to and during the evening peak yesterday introduced a generation capacity shortage within the peak period that unfortunately could not be replaced otherwise,” Marokane said the group is reviewing “its protocols” to enable it to issue warnings earlier.