In a statement on Thursday afternoon, Eskom confirmed that it had uncovered additional sabotage at its Tutuka Power Station near Standerton.
Earlier in the day, News24 reported that a warming valve cable was cut with a grinder at the weekend.
Eskom spokesperson Sikonathi Mantshantsha told News24 that the act was committed just outside the sight of the CCTV cameras, "clearly by someone internal who knows very well that the camera around the area is not facing this specific point". It was also understood that the area where the cable was cut was not accessible to intruders without authority to access the plant itself.
A list of all employees who were on shift during the incident has been submitted to the police.
"The damage to the cable had the effect of delaying the unit’s return to service by three days as it took some time to locate the fault," Eskom said in a statement on Thursday.
It added that it also discovered another act of supposed sabotage: it found that the control air pipe supplying the Unit 5 Turbine systems at Tutuka had been cut with a power tool and the entire bend removed.
This led to a drop in air pressure at the station’s station control.
The pipe was welded to restore the air pressure, and the unit is now expected to return to service later on Thursday.
"Eskom believes these were deliberate acts of sabotage by someone who had access to the site where only employees have access and knows the security features in the area quite well," on Thursday.
Eskom has laid criminal charges with the police, and its forensic team is assisting with the investigation.
This is the fifth incident of sabotage at Eskom since March 2021.