As Eskom continues to experience power capacity constraints, acting general manager Thomas Conradie says the power utility will implement Stage 3 and 4 load shedding this weekend.
“We are forced to continue applying the Stage 4 load shedding over this weekend in the same pattern as what we have previously done. This is because we need to rebuild our reserves and recover some of our coal stock levels due to heavy rains as well as a plant problem on one of the conveyer belts” Conradie said.
he also said the heavy rain experienced especially from the east has impacted power stations towards the east of Mpumalanga and the Vaal.
“In the past three years we have been working on improving what is called rain readiness to ensure that we can best deal with the rain situation. It helps to have adequate coal reserves for shorter spells of very heavy rains.
“During long rainfall spells, all your dry and seasoned piles become wet in the process, yet we are doing well in managing the situation. It did however cause us to see increases in partial load losses, where generating units are on load but we need to run them at lower loads,” he said.
Due to that, Eskom has recorded total unplanned plant unavailability of about 17 000Megawatts (MW), hence the implementation of Stage 3 loadshedding during break times and escalation towards Stage 4 load shedding over the evening peak from 4pm until 5am.
“We have had a number of units that have returned to service and we are still planning to return another Duvha Power Station in Mpumalanga today, which has been out for a considerable time due to a forced outage as well as Lethabo 4 Power Station in the Free State, which was also out due to an outage.
“This will give some relief. The situation is such that we have been dispatching diesel a lot during this past week and equally using our pump storage, although the pump storage is looking healthier than what we have seen in the past,” Conradie said.
Eskom has indicated that it needs to rebuild its reserves and recover some of coal stock levels after heavy rains.
“With that in mind, we will therefore be forced to apply Stage 3 and Stage 4 load shedding into this weekend and currently projected for Monday, where we see normally a marked increase in demand as we approach the new work week,” he said.
In terms of the diesel reserves, the power utility has adequate offsite storage and offsite diesel available.
“Our onsite levels of diesel is quite low so we need to utilise the time over the weekend to transfer diesel from the offsite storage to the onsite storage in order to be well set up for the coming week.
“In terms of the longer term planning, we are still running with a significant number of units at risk. Currently we have about 4 700 MW of plant running with risk, meaning they can at any stage let us down and that’s unfortunately the levels of unreliability and unreadability that we are sitting with,” Conradie said.
Eskom foresees a unit returning on Saturday, a further two units on Sunday and a further four to pick up for Monday’s further demand.
“In the coming weeks and until March, there are a number of units that need to return from planned and forced outages so we aim to return seven generating units of different sizes over the next couple of weeks and into March.”
“We are still very much in the outage season, so a lot of work will be done on units and this will continue right through March,” he said.
Eskom will slightly increase plant maintenance in the latter part of March. This will also ensure Eskom has the machines in the best conditions as the country approaches the winter months.
“In terms of the system, we are not where we want to be yet in terms of getting our total unavailability down, the 17 000 MW is too high.”