Sunday, 22 January 2023: Eskom appreciates and is fully aware of the difficulties caused to the public and the economy by the continuing power capacity constraints. Eskom would like to apologise to the people of South Africa for these difficulties and to assure the public that, together with the government and other stakeholders, we are working with urgency to resolve the generation capacity constraints and to reduce the loadshedding as soon as possible.
The reality, however, is that resolving the problems impacting the performance of the generation coal fleet will take longer than South Africa wants and needs.
The October 2022 failure of the chimney system at the Kusile Power Station, which removed more than 2 000MW of capacity, is the major cause of the elevated stages of loadshedding. This, together with the planned extended outage of Unit 1 of the Koeberg Nuclear Power Station, are responsible for three stages of loadshedding. Eskom is making every effort to reduce the duration of these outages as much as possible.
Although the stages of loadshedding have been high and for extended periods, this does not indicate that the power system is approaching a blackout. In fact, loadshedding is implemented to ensure the appropriate reserve margins are maintained to manage the risk of a blackout. Therefore, there is no higher risk of a blackout than normal.
As communicated regularly in the past, Eskom is grappling with deep structural and maintenance problems in its current and ageing fleet of generators, which are on average 45 years of age this year, which is in the context of the typical 50 years design operating life of a power station.
In this context, Eskom reiterates that the only way to end loadshedding is to add additional capacity. The shortfall is currently estimated at 4 000MW – 6 000MW of generation capacity. This supply deficit can only increase as the current fleet gets on in years and its performance continues to deteriorate.
Eskom would like to thank the government for the interventions that have so far helped procure some additional generation capacity through the Independent Power Producer Office, as well as regulatory amendments to enable embedded generation investors to add new capacity.
These projects are estimated to exceed 9 200MW and will, when they come online, help relieve some of the pressure and help reduce the occurrence of loadshedding.
Further, both Eskom and the government are expeditiously making efforts to acquire additional generation capacity from existing operators, both within South Africa and the region.
It must be noted, however, that the problem requires much requires more intensive interventions to sustainably resolve the current challenges. It is critical that the criminal syndicates who are stealing coal and spares, and who commit sabotage, be brought to book. Eskom welcomes recent arrests, as well as the deployment of the South African National Defence Force and requests a redoubling of efforts in this regard to apprehend the leadership of the syndicates.
For its part, Eskom is working hard to execute maintenance of the power station fleet to improve reliability of the generating units and to improve the energy availability factor. Planned maintenance, currently at 6 022MW (approximately 11% of installed capacity), is optimised during the summer months and will taper off towards the high demand winter period. This is to ensure maximum availability during the winter, to meet as much demand as possible.
In addition to the planned maintenance programme, Eskom is focusing on returning as much of the units with long-term breakdowns as possible. The target is to return about 6 000MW of generating capacity onto the grid during the next 24 months. These are in the Top 6 target power stations. Each power station has detailed recovery plans.
Progress is being made in returning Unit 4 of the Medupi Power Station, which suffered a generator explosion during August 2021. The unit is anticipated to return to service during September 2024. Eskom continues to explore options to reduce the time to repair the unit.
Update on Kusile Power Station chimney failure
- The Kusile Unit 1 flue duct (chimney) failed on 23 October 2022 when the duct bend collapsed. The bend collapsed due to excessive weight of slurry deposited in the flue, owing to design defects in the boiler, and subsequent adverse operating conditions in the flue gas desulphurization unit (FGD).
- This incident compromised the adjacent Unit 2 and 3 flue duct bends, making all three units inoperable. This removed a total of 2 160MW from the power system.
- Further investigation of the failure incident, in conjunction with the original equipment manufacturer, has revealed that there is excessive ash slurry build up in all three units’ flues, adding excessive weight which compromised the integrity of the flues and the chimney.
- Temporary flues for the units will be constructed to help return the units to service while repairing the common chimney. It is anticipated that the design and construction of the temporary stack will take up to 12 months.
- To achieve this, Eskom will seek exemption from the Department of the Environment, Fisheries and Forestry to temporarily operate the units while bypassing the FGDs with the temporary stacks.
Together, the three Kusile Power Station units, combined with Medupi 4, are responsible for the shortfall of approximately 2 900MW in generation capacity – equivalent to three stages of loadshedding.
In addition to the above, the Koeberg Nuclear Power Station will continue operating at half of its 1 800MW generating capacity for the next 15 months. Unit 1 is currently on a regular refueling and maintenance outage that will include the replacement of the three steam generators as part of the requirement and preparation of the unit for long-term operation. It is anticipated the unit will return to service during June 2023.
Koeberg Unit 2 will undergo a similar outage starting in September 2023. It is anticipated this will take approximately six months to execute. Upon successful execution, the combined investment in both Koeberg units will secure 1 800MW of generation capacity for a further period of 20 years, subject to regulatory approval. An application for the licence extension was lodged with the Regulator in July 2022.
The gas air heater fire, while in the custody of the contractor, during September 2022 resulted in the delay in the commissioning of Unit 5 of Kusile Power Station and has also removed a possible 720MW from the grid. Efforts are being made to expedite the repairs and to bring the unit online within the shortest space of time. Current indications, however, are that the unit’s commissioning has been delayed by approximately 12 months. It is anticipated the unit will be synchronised to the grid during July 2023.
Together, these long-term projects and breakdowns are contributing to the high levels of breakdowns and have set Eskom back at least 4 500MW of generation capacity, equivalent to five stages of loadshedding. This makes for a further elevated risk of loadshedding while to repair these is in progress.
Stage 3 loadshedding will be implemented from 16:00 this afternoon until 05:00 on Monday morning. Stage 2 loadshedding will be implemented during the day at 05:00 – 16:00, whereafter Stage 1 loadshedding will be implemented daily.
On Monday afternoon Stage 4 loadshedding will be implemented at 16:00 – 05:00. Evening loadshedding will then be reduced to Stage 3 daily from Tuesday until further notice.
Six generating units are anticipated to return to service during the week, which will enable Eskom to maintain loadshedding at the lower stages in this period.
There is considerable risk to this outlook, however, as the coal plant is highly unreliable and unpredictable. Should further significant breakdowns occur, Eskom would be required to change the stage of loadshedding at short notice.
Planned maintenance is 6 022MW of capacity while generating capacity currently unavailable due to breakdowns amount to 14 372MW.
While the current shortage in generation capacity prevails, it is important that all users of electricity use electricity sparingly, particularly during the evening peak hours. The National Energy Crisis Committee (NECOM) are working with Eskom to implement demand management measures, including incentives for loadshifting, feed-in tariffs, and other efficiency measures. While these are being implemented, South Africans are urged to conserve energy by switching off unnecessary lights, and being conscious of the cumulative impact of every Watt of electricity that can be saved.