Despite the ever-present threat of load shedding, Eskom staff recently made a huge mistake that almost resulted in the loss of the 970 megwatt (MW) unit 1 at the Koeberg nuclear power station.
The generation capacity is virtually equal to one stage of load shedding.
This “significant incident” came while unit 2 at Koeberg is unavailable for power generation after it was taken offline on January 18 for refueling and maintenance. It is due to return to service in June.
According to an internal Koeberg newsletter “an individual” who was doing maintenance on unit 2 cut a valve of unit 1 instead of unit 2.
“In the light of this, we have had to implement a work stop following a significant event, which could have resulted in us losing the running unit,” the newsletter states.
Daily Maverick picked this up and published the relevant page on Thursday. Eskom has confirmed the authenticity of the newsletter.
The newsletter further discloses that this is the second time this has happened. “This speaks to very poor human performance, and it is an unacceptable practice,” it states.
It implies that there is no excuse for such a mistake: “We are equipped with the relevant training to correctly identify the unit and component we are tasked to work on,” and cautions staff to read the signage.
This near-miss is the latest in a string of Eskom blunders that are costing money and megawatts.
Lack of preparation
Earlier this month Eskom was forced to defer the replacement of the steam generators at Koeberg’s unit 2 due to its own lack of preparation.
The replacement is part of a R20 billion project to extend the life of Koeberg by another 20 years beyond its current lifespan, which ends in 2024.
The generator replacement was due to take place during the current outage, but it became clear that Eskom’s poor preparation would result in a time overrun. Eskom announced the deferment because such an overrun would increase the risk of load shedding in winter.
The replacement is now due for late next year, which means an additional five-month outage that South Africa’s constrained power supply system can hardly afford.
In addition, Eskom will probably be heavily penalised by the French contractors who were on site already and have dedicated resources for this project for the next couple of months.
Eskom has not yet been able to quantify such penalties.
Unplanned capability losses dominate …
According to Eskom’s data portal, 28% of its generation capacity has been unavailable due to unplanned breakdowns during March. This is the highest monthly average in the last two years.
The following chart from Eskom shows a breakdown of monthly generation capacity as at March 17, 2022.
This is monthly ratio between available Eskom plant and all unavailabilities expressed as a percentage, where:
A significant portion of these breakdowns also relate to Eskom blunders.
- The explosion in 2014 that severely damaged Duvha unit 3. It occurred after Eskom changed the kind of coal it used following the breakdown of its conveyor belt. The utility failed to manage this properly, which led to over-pressurisation and ultimately an explosion. Although insurance paid out R4.2 billion, the unit has not yet been repaired.
- The explosion at Medupi unit 4 late last year after staff failed to follow prescribed protocols. It has robbed the system of almost 800MW and will cost R2.4 billion to repair. It is expected to be back in service by 2024.
- Eskom last year disclosed that its Tutuka Power Station in Mpumalanga was in a “shocking state” and replaced the power station manager. Among other things, the head of generation disclosed that maintenance work that was signed off was seemingly not really done. Eskom also discovered that fuel oil to the value of R100 million was stolen every month. It is not clear how long this had been happening. Eskom has been battling to restore Tutuka to a level where it performs adequately. During the latest round of Stage 4 load shedding only two units were running, which means that more than 2 400MW was unavailable for power generation.
- Eskom’s newly built Medupi and Kusile power stations have been performing poorly due to design flaws. The utility did its own project management and the projects were years overdue and billions over budget. Some repairs have been done at Medupi, which has resulted in improved performance, but Eskom head of generation Phillip Dukashe admits that they are not running as well as would be expected from new plant.
- Energy expert Chris Yelland points out that Eskom failed to repair dust extraction and dust handling equipment that broke years ago at its Kendal Power Station. This has resulted in extensive pollution and Eskom is facing criminal charges in this regard. It is now embarking on these repairs, which means the units have to be taken offline, robbing the grid of more than 600MW of generation capacity per unit.
Apart from the loss of generation capacity due to carelessness, the additional cost it incurs as a result consumes the little money the utility has for plant maintenance.
Lower maintenance levels increase breakdowns, and so the vicious cycle continues.
In a recent presentation to the National Economic Development and Labour Council (Nedlac) Eskom showed several scenarios going forward.
In the period up to April 2023 its forecast shows if, with unplanned breakdowns of between 12 000MW and 13 000MW Eskom will have to spend more than R20 billion on diesel for its open-cycle gas turbines (OCGTs).
This is about double the amount spent on its own and private OCGTs in the current financial year – and was calculated in January, before diesel costs soared on the back of the conflict in Ukraine.
Eskom CFO Calib Cassim however tells Moneyweb that Eskom simply does not have the cash flow to spend so much on diesel.