Medupi magic fails Eskom, SA
REVEALED: PROBLEMS AT PLANT LED TO LOAD SHEDDING
Staff at Medupi dismissed for negligence.
Following major problems that brought Eskom’s Medupi power station to its knees during the height of the load shedding last week, Medupi’s power station manager, Rudi van der Wal, is leaving Eskom to take up a position overseas.
Van der Wal had resigned before the mess started and was due to leave in about two weeks. But following the events last week was made to step aside before his pending departure.
Other staff at Medupi have been dismissed by Eskom’s head of generation, Bheki Nxumalo, for negligence, in what Eskom COO Jan Oberholzer calls “consequence management” following several major problems at Medupi that contributed to the load shedding last week.
Additional problems at Medupi have now been identified that had not been previously disclosed to the public by Eskom’s management.
For some time, the stackers that load coal from Exxaro’s Grootegeluk mine onto the stockpiles at the Medupi stockyard, and the reclaimers that take coal from the stockpiles to feed coal by conveyor to the power station boilers, have not been working.
So, to get fuel to the Medupi boilers, the coal stockyard was bypassed, and the single main coal conveyor feed from Grootegeluk mine was feeding the power station directly, without any redundancy in the system.
So, effectively, Medupi was running with minimal coal stock at its disposal.
Thus, when the 4.5km single main coal conveyor feed from the Grootegeluk mine failed on Eskom’s side with a broken belt, Medupi was left with no coal feeding its boilers other than about one or two shifts worth of fuel in the bunkers at each boiler.
To add to the disaster, it is now clear that blocked chute and belt rip detectors on the conveyor were not working. Thus, the conveyor did not trip when it should have done in order to protect the system.
This caused damage to about 700m of belt, as well as damage to the conveyor structures.
With the main coal conveyor from Grootegeluk mine down, and the stacker/reclaimers at the Medupi stockyard not working, coal now had to be transported by truck from the stockyard, for offloading at the emergency Buffalo conveyors at the boiler bunkers, in order to get fuel to the boilers.
This posed a major logistical nightmare due to the huge volumes of coal involved. Major congestion of coal trucks transporting coal from the stockyard to the bunkers forced the power output of Medupi to be reduced to a third of normal, thus contributing to load shedding.
Then problems were experienced with the ash-handling plant, which conveys ash from burning coal in the boilers to the ash dumps. Staff working on the bunker feed problems were shifted to deal with the huge buildup of ash, thus compounding the problems.
The good news is that the main coal conveyor from Grootegeluk mine is expected to be operating again shortly, thus relieving the logistical problem of transporting coal by truck and manually offloading the coal at the emergency Buffalo conveyors to feed to the boiler bunkers.
The bad news is that the stacker/reclaimers are still not working. So, with the coal stockyard bypassed, Medupi remains vulnerable and dependent on a single, long, conveyor feed from Grootegeluk mine, without any redundancy if the conveyor should fail or trip.
Chris Yelland is the investigative editor at EE Publishers.
The conveyor did not trip when it should have