Power utility Eskom on Thursday said that in the case of the recent power outages in the Western Cape it accepted that there were oversights regarding some of its practices and procedures. However, this did not mean that Eskom had been negligent.
Every technical fault did not amount to a breach of a licence condition or negligence, it added.
The power utility was responding to a probe by the National Electricity Regulator of South Africa (Nersa) into the recent power outages in the Western Cape, which found Eskom guilty of transgressing its licensing conditions as well as negligence.
Eskom chief executive Thulani Gcabashe said that Eskom’s own investigations into the seven incidents had confirmed that its planned maintenance was properly implemented within the challenges and constraints of a complex operating environment.
“However, areas for improvements have been identified. These included recommendations regarding equipment and systems, procedures, plans and studies and organisation learning strategies.
“All of these have been prioritised and put into action plans that are being monitored at the highest levels of management. More than 50% of the recommendations have already been implemented while others can be regarded as work in progress,” Gcabashe said.
The efficacy of Eskom’s corrective actions had been acknowledged by Nersa in their report, he said.
“Among our specific concerns regarding the Nersa report are that they relied on isolated facts to draw conclusions of negligence and failed to explain why they chose certain facts above others.
“In our opinion, such a finding requires careful consideration of all the relevant facts and circumstances, including the reasons for certain actions or omissions, all in the context of running a complex electricity business. No legal analysis of the facts to sustain a finding of negligence was undertaken.
“We disagree with Nersa’s interpretation of both the grid code conditions and their view as to what amounts to a breach of licence conditions,” Gcabashe said.
Referring to a specific incident at Koeberg on December 25 last year, which resulted in a shutdown of unit one, Eskom said its Corporate Technical Audit Department (CTAD) had found that an unknown foreign object had damaged insulation in the generator, resulting in a stator earth fault and widespread damage to the generator.
“The investigators said that it is known that loose magnetic objects in a generator can thermally or mechanically damage insulation, with consequent inter-turn faults and/or phase-to-phase faults. This is considered to be the most likely explanation of the failure, a conclusion supported by fault-recorder data.
“The report says the most probable cause of the incident is the failure of clean-condition controls during the repair process.”
Clean-condition procedures were implemented during repair work on generators in an attempt to prevent tools or equipment such as bolts, washers and screws being left behind, Eskom added.
“It is regrettable that investigators were not able to make a specific finding as to the precise circumstances that led to the failure of the generator. Based on the circumstantial evidence, I am inclined towards the view that we are dealing with human error rather than any deliberate act or omission,” Gcabashe said.
“This was a mechanical failure in generating equipment outside of the nuclear unit itself and Eskom can give categorical assurance that that at no stage of the incident was there a health or safety risk to the people of Cape Town.
“Indeed, Eskom’s nuclear safety protocols, which fall under the control of the Nuclear Regulator, remain inviolate, as demonstrated by regular peer reviews by auditors from international bodies such as the World Association of Nuclear Operators,” Gcabashe added.
He added that Eskom had ensured that the necessary corrective actions had already been implemented in all relevant areas of its business.
“Notwithstanding the challenges of the past year, Eskom has demonstrated its ability to take corrective action and stabilise the supply network in the Western Cape. We sincerely regret the inconvenience caused to our customers and members of the public as we came to terms with the challenges.
“We are deeply conscious of a number of shortcomings and acknowledge that there is room for improvement. Eskom has a long and proud history of excellence and we are determined to win the trust and admiration of all South Africans. We will redouble our efforts to achieve this goal,” Gcabashe concluded. — I-Net Bridge