South Africans will know more about the current status of the country's electricity supply on Wednesday, when Public Enterprises Minister Pravin Gordhan and Eskom board chair Jabu Mabuza address media at a power station 90 minutes outside of Johannesburg.
The department of public enterprises, under which Eskom falls, has not disclosed the name of the power station "for security reasons".
Eskom stopped implementing load shedding on March 24, after the stability of the power grid was restored following a a series of unplanned breakdowns of generating units and a cyclone in Mozambique. But even then, the power utility warned that rotational power cuts could not be ruled out entirely.
Gordhan and Eskom management previously held a briefing about the load shedding crisis on March 19. At the time, the minister said that a report back would be provided in 10 to 14 days' time.
This is what we know about the state of the electricity system:
No guarantees load shedding is over:
At the previous media briefing two weeks ago, Gordhan could not say when load shedding would be over. He said government was still trying to understand the technical problems at the power utility, Fin24 reported.
Earlier in March, a 11-member technical review team was appointed to assess the operations of power stations to try and get to the cause of plant failures, unscheduled maintenance and inefficiencies. The team was mandated to provide a report within four weeks.
Poor maintenance for an ageing fleet:
Eskom chair Mabuza said two weeks's ago that the debt-laden power utility is battling with an ageing fleet and that over the past five years expenditure on plant maintenance had been reduced. He said that the diversion of these funds was being investigated.
The utility's CEO Phakamani Hadebe said it has set aside R50bn over the next five years for maintenance as ageing infrastructure is unable to keep up with electricity demand.
Boiler tube leaks behind plant breakdowns:
At the briefing on March 19, Eskom's leadership said that the loss of generating units was the cause of power cuts. And the single biggest cause of plant breakdowns at seven generating units was boiler tube leaks.
Chief Operating Officer Jan Oberholzer explained that a contract for an early detection mechanism for leaks had lapsed 18 months ago and was not renewed. Steps were being taken to tender for a new contract.
In a separate interview with Fin24, acting head of generation Andrew Etzinger said that engineers at power stations are still able to flag leaks, but the early detection tool helps to make early detection possible.
Recovering coal levels:
According to an internal memo circulated in March, Oberholzer said that coal stock levels are recovering.
At the time, Eskom was on track for meeting month-end targets.
"Only three out of 15 stations are now below the target of 15 days and recovery is on track to achieve 33 system stock days (excluding Medupi and Kusile) by 31 March 2019," the memo read.
Design defects at Medupi:
According to the internal memo, there are five key design defects at Medupi power station, which was meant ensure that Eskom would have enough available capacity to meet rising demand. Eskom has placed a team at Medupi to address its operational challenges.
Medupi contributed the most to power trips, which resulted in poor system performance. The boiler tube leaks in turn, are causing trips.
A third-party expert is also assessing Ingula power station. According to the memo, a way forward for this station would be known by the end of March, Fin24 reported.
A contributing factor to the load shedding was shortage of diesel supplies to power open cycle gas turbines. Etzinger told Fin24 these turbines are only meant to be operated between two to three hours a day over peak periods when demand for electricity is high. However, these plants were being relied on for up to 14 hours a day, which depleted diesel reserves faster than the rate at which they could be replenished.
Eskom managed to get 13 million litres of diesel reserves from state oil company Petro SA, which helped reduce load shedding from Stage 4 to Stage 2.
Etzinger said that Eskom is working on an arrangement with Petro SA to increase the availability of diesel proactively to avoid supply constraints when the open cycle gas turbines have to be run for 14 hours a day.
So far Eskom has spent R4.5bn on emergency diesel, much more than the R600m budget. Etzinger said that Eskom plans to budget R7bn for diesel in the next financial year, Fin24 reported.
Impact of Mozambique cyclone:
A major contributor to the load shedding experienced in March was the power imports from the Cahora Bassa dam in Mozambique, which were compromised following cyclone Idai. Eskom imports 1 500 MW from the dam, but lost 900 MW. One of two power lines were restored, which helped get back 850 MW, Eskom said in a previous statement announcing that load shedding would be suspended.
Class action law suit:
Eskom had implemented Stage 4 load shedding, which allows 4 000 MW to be load shed on a rotational basis, while still meeting 80% of electricity demand.
Law firm De Beer Attorneys on Tuesday called for businesses who suffered financial losses due to load shedding to join a class action lawsuit against Eskom, Fin24 reported.
'The energy crisis will pass'
President Cyril Ramaphosa has compared the challenge of load shedding to apartheid. The president told a rally on Human Rights Day that restoring electricity supply is an urgent priority and that the electricity crisis would be overcome, just like apartheid had been overcome.
"We will overcome this electricity crisis engulfing the country at this moment. We will overcome it just as we overcame the apartheid challenge. Just as we will overcome poverty, crime and corruption … We will overcome because we are South Africans," he said.
The briefing is expected to be held at 14:00, after journalists get a chance to tour the power station.