ESKOM will approach the Department of Forestry, Fisheries and the Environment (DFFE) for an exemption to allow it to temporarily bypass the flue gas desulphurisation (FGD) units at the Kusile power station in an effort to reintroduce 2 160 MW of production, months earlier than would be the case absent such an exemption.
Kusile Units 1, 2 and 3 have been out of service since October 23 after the flue duct at Unit 1 failed as a result of the duct bend collapsing, owing to excessive weight of slurry deposited in the flue.
The incident also compromised the adjacent Unit 2 and 3 flue duct bends, making all three units inoperable, which has precipitated an intensification of loadshedding by two stages.
It is currently estimated that a full repair, which will involve increasing the height of the smokestacks to 90 m, could take 18 months.
However, Eskom aims to introduce temporary flues for the three units to enable an earlier return to service, while the longer-term solution is implemented on the common chimney.
COO Jan Oberholzer indicated during a briefing on January 22 that the design for the temporary stacks had been completed and that it would be technically possible to bypass the FDGs and, thus, reintroduce the units about eight months earlier.
However, a temporary exemption would be required from the DFFE to enable it to bypass the air-pollution control system, which has been a regular source of trips at Kusile, and Oberholzer confirmed that Eskom would be making a formal request to the DFFE in this regard.
The move is likely to face some resistance from environmental groups, but the authorities are likely to prove sympathetic given growing public anger over power cuts and even some legal demands for Eskom to immediately halt loadshedding.
After South Africa’s worst-ever year for rotational power cuts in 2022, loadshedding has already been implemented on every day of 2023 so far, at times at Stage 6, and the outlook for the rest of the year remains bleak.
The recovery of the three Kusile units, as well as the synchronisation to the grid of Kusile Unit 5 later this year, forms part of a larger board- and shareholder approved generation recovery plan to deliver more than 6 000 MW of Eskom generation over the coming two years.
Besides the rebuilding of Medupi Unit 4, which is out of service owing to a hydrogen explosion, much of the recovery is expected to arise from the six underperforming coal stations of Kendal, Matla, Majuba, Duvha, Tutuka and Kusile.
Acting generation executive Thomas Conradie reported that the intention was to add 6 274 MW over a 24-month period, including 1 862 MW in the coming six months, an additional 1 530 MW in 12 months, 1 818 MW in 18 months and an additional 1 064 MW in 24 months.
The board operations performance committee had requested the appointment of WSP Africa to monitor and report on the implementation of what is described as a “complex project management exercise”.
Loadshedding would still be required over the period, however, to create “headroom” for the maintenance required to stabilise the coal fleet and raise Eskom’s energy availability factor (EAF).
The average year-to-date EAF has been about 58% (with the coal fleet operating at an average EAF of about 52%) to a nominal 60% by the end of March. The goal is then to increase the average EAF to 65% by the end of March 2024 and to 70% by the end of March 2025.
The briefing exposed a divergence between the board and the executives over the implementation of loadshedding, with chairperson Mpho Makwana indicating that there would be “permanent Stage 2 or 3 loadshedding for the next two years in order to give sufficient space for maintenance” and the executives indicating that higher stages would probably be required at times, while no loadshedding would be implemented if there was sufficient energy available to avoid such cuts.
Following the briefing Eskom indicated that it could not guarantee that loadshedding would remain at between Stages 2 and 3 and that it was, thus, inaccurate to state that there will be permanent Stage 2 and 3 loadshedding.
Outgoing CEO André de Ruyter and Oberholzer also re-emphasised the need to introduce between 4 000 MW and 6 000 MW of new generation to both create the time and space required for maintenance and to cater for the retirement of coal stations.
DYNAMIC MARKET MECHANISM
Beside the EAF and burning more diesel, De Ruyter said there were two options for increasing supply in the near-term: implementing Eskom’s standard offer to buy power from companies with surplus capacity, as well as the implementation of a “dynamic market mechanism”, under which bids could be invited on a day-ahead basis to supply electricity into the grid.
Together, these two mechanisms are expected to be able to secure about 1 000 MW of additional supply, with money for the standard offer having been approved recently by the regulator.
“[Regarding] the dynamic market mechanism, we are already simulating a day-ahead market [and] we are advertising on the Eskom website so there are bids into the pool as we speak.
“With the assistance of the good officers of the National Energy Crisis Committee (NECOM) we are awaiting an imminent approval, hopefully within a matter of days, of the implementation of this dynamic market and we think that this is indeed a very exciting development and a very promising development,” De Ruyter said.
The outlook for the purchase of more diesel over and above the additional 50-million liters purchased on January 6 was less certain, with Makwana saying only that the board investment and finance committee was working on funding mechanisms.
“The board will soon be able to approve a funding model for the diesel procurement,” he added, without providing details, including whether the National Treasury was willing to assist with any funding.
De Ruyter also underlined the need to continue with the unbundling process, especially the operationalisation of the National Transmission Company South Africa (NTCSA), which he described as a “critical enabler” of new generation.
“This is one of the key work streams at NECOM and there is a lot of work going on to enable that and to ensure that there is appropriate attention paid to enabling legislation.
“I obviously can’t speak on behalf of government when it comes to legislation and when that will be submitted to Parliament for its consideration, but I can give the assurance that this is receiving very high priority from The Presidency itself in order to put together enabling legislation that will allow for the operationalisation of the NTCSA on an expedited and urgent basis.”
He also reiterated that he felt that a large portion of the $8.5-billion in concessional funding pledged for South Africa’s Just Energy Transition Partnership Investment Plan should be directed towards building grid infrastructure in areas with strong renewable resources, such as the Northern Cape.
FOOD SECURITY IN FOCUS
Eskom also expressed sympathy for calls arising from the agriculture sector for some protection from extreme loadshedding, which had the potential to undermine food security.
“While every industry in the country will probably say that they are a special case, I think agriculture really is because you have crops that need irrigation and you have refrigeration, that all require electricity.
“We are putting in place engagements with farmers and with agricultural societies to see how we can assist farmers, particularly when loadshedding is at exceptionally high stages.”
Oberholzer indicated that the current tariff structure and loadshedding standard might need to be reassessed in the interest of ensuring food security and continued export production.
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