NATIONAL NEWS - With load shedding likely to last for months to come, Tshwane metro’s infrastructure continues to take a knock during these power surges.
“Pretoria’s electricity infrastructure, especially in the east, was negatively affected from the constant outages,” said MMC for utility service in Tshwane Phillip Nel.
Nel said this led to the tripping of electricity grids and surges due to overloading.
During load shedding switching, the turning on and off of electricity to a grid happened up to three times per day, but the “real killer” he said was that the load was synchronised.
“All geysers, pumps, heaters, air conditioners, etc, start simultaneously. The start-up current of rotating machines like pumps and compressors is up to three times higher during the first few seconds,” he said.
“Precautions are necessary to limit negative effects of load shedding as Tshwane teams deploy to manage any prolonged outages.
“It is this concentrated load that sometimes is high enough to trip a circuit breaker, but the peak current is also high enough to cause a blow out on the joints of the 11kV cables buried underground, for example.”
In the past weeks, residents in various parts of Pretoria were hit by prolonged power outages which Nel said were attributed to Eskom’s implementation of load shedding.
Some residents in the north of Pretoria took to the streets to demonstrate over prolonged electricity cuts.
Clarina residents blocked the roads with burning tyres demanding that their electricity be restored after a 40-hour outage.
The inability to attend to these cuts was further exacerbated by protesting employees affiliated to the South African Municipal Workers Union (Samwu) which limited the workmanship available to restore power.
Nel said residents could help the situation and help the metro limit the negative effects of loadshedding by switching off all rotating machines, heaters and geysers before the planned reconnection time.
“When power is restored, wait a few minutes before boiling the kettle and resuming cooking. Switch geysers, pumps, etc, on only after power has definitely stabilised.
“The above can be achieved by switching off all circuit breakers excluding lights during the power out period. The lights will confirm when power is restored and other circuits can then be switched on gradually after power is stable.
“It will also protect electronic equipment. We all need to work together to protect our electricity infrastructure.”
By limiting the initial load on the system he said residents would help protect the grid from tripping and power outages.
This week Eskom warned that its system was likely to remain severely constrained for the near future forcing it to continue load shedding into the summer.
In its state of the system briefing a week ago, Eskom shared its plan to continue with load shedding into the summer season.
“Our objective is to achieve a reliable and sustainable generation plant, thereby reducing the risk and frequency of the occurrence of load shedding. As such, Eskom will not compromise on reliability maintenance and mid-life refurbishment,” said Eskom chief operating officer, Jan Oberholzer.
“However painful in the short term, we have to do this maintenance in order to ensure future reliability.”
He said through the accelerated maintenance programme, Eskom hoped to continue reducing the occurrence of load shedding, which he said was effective during the winter season.
Eskom conceded load shedding carried a significant damaging effect on the economy.
“We are aware that the increased maintenance does elevate the probability of load shedding in the short term, but this is necessary to improve the future performance of the generation fleet,” Oberholzer said.
