Brace for a week of power cuts - Eskom blames lack of maintenance
A critical mechanical failure on a conveyor belt transporting coal to Medupi power station and scores of boiler pipe leaks are what has brought on Wednesday's load-shedding.
Eskom COO Jan Oberholzer, in an interview with TimesLIVE, said mechanical teams were en route to the conveyor belt which went down at 9am.
He said the belt fed coal from mines to the power station. The structural damage - which would take until the end of the month to repair - had reduced Medupi's 4,000MW output by a third, he said.
"At this stage we simply do not know what has happened. We do not believe that it is sabotage or old age as the power station and the belts are relatively new. The mechanical teams will have to determine exactly what happened. The problems look as though they were at the pulley systems which saw the belts wrap around the pulleys."
In regards to the boiler leaks, Oberholzer said they had lost six boilers since Saturday, with Eskom being forced to keep another three, which are leaking, in operation.
He said they believed the six boilers, two of which went down on Tuesday, would be back on line by the end of the week.
"We are, however, sitting with three other leaking boilers, which we will have to take off line soon to repair."
Oberholzer said the leak problems were occurring because proper maintenance had not been done.
"Each boiler has on average 600km of tubing. It's not an overnight thing to fix.
"When it comes to maintenance, teams go through the pipes and check for both where the leaks are and where they are likely to occur. If you have not done maintenance these problems [leaks] occur."
He said because of the dangers to the economy from having the entire power supply system trip, they had to do controlled shutdowns.
"Since Saturday we have had to make use of emergency diesel supplies to keep the lights on. We did this in part by running our open-cycle gas turbines. Unfortunately we are burning far too much diesel. We have nine such turbines, with each turbine costing up to R750,000 an hour to operate."
He said the open-cycle gas turbines were meant to run only at peak times and during emergencies, but since Sunday they have been run more than that.
"On Sunday they were running throughout the day.
"We cannot afford it but if we do not, the cost to the economy will be far higher. That is why from Tuesday night we decided we had to implement stage 2 load-shedding to protect the integrity of the reserves, our systems and the economy."
Oberholzer said Eskom had also been operating its water pump stations around the country.
He said they believed that load-shedding would last for a week.
Oberholzer said while they had the right people to fix the problems, it would take time.
"The boiler leaks, and the problems associated with them, will be with us for some time, especially as there are another three boilers which we are running which all have leaks."