OUTAGES EXPLAINED: Pushing the limits: Why load shedding puts even more pressure on an ageing electrical system

2022/06/27 23:43:00

The frequent switching on and off of load centres is putting additional pressure on an already overloaded system, which is why you might still be sitting in darkness even after load shedding was meant to end.

The frequent switching on and off of load centres is putting additional pressure on an already overloaded system, which is why you might still be sitting in darkness even after load shedding was meant to end.

The frequent switching on and off of load centres is putting additional pressure on an already overloaded system, which is why you might still be sitting in darkness even after load shedding was meant to end.

by Julia Evans, Daily MaverickJune 27, 2022Pushing the limits: Why load shedding puts even more pressure on an ageing electrical system by Julia Evans, Daily Maverick June 27, 2022 Johannesburg's power utility City Power's ageing infrastructure is not coping with the demands of Stage 4 load shedding. Communicating with residents through a ward WhatsApp group, Nicolene Jonker, DA councillor in the City of Johannesburg, told residents on Monday that “City Power can’t cope with Stage 4 load shedding. Half the operators are busy switching load centres on and off every two hours for load shedding, and the number of substation trips from inrush current after load shedding is very high.” Isaac Mangena, spokesperson for City Power Joburg agreed with her assessment, telling Daily Maverick that Stage 4 was putting too much strain on their resources, with some substations unable to return during restorations, leaving customers without power for a longer period. “Load shedding has undesirable effects on the infrastructure which, by its nature, was never meant to be switched on and off at short intervals, and comes with it added financial pressures that we did not budget for,” said Mangena. Mangena said that at the weekend they fielded more than 5,000 outage calls and by 6am on Monday, they were dealing with almost 2,700 calls — more than 2,000 of them in 24 hours. Most of the outages have been backlogged since Friday, with Randburg, Reuven and inner-city areas hit the hardest most of last week and into the weekend. Residents have taken to social media to express their frustration and confusion about why they still do not have electricity outside scheduled load shedding. Ok now it’s 16:40 and still@no power after loadshedding? After our 6 hour outage this morning. Loadshedding is ridiculous enough as it is and even it doesn’t work properly. Absolutely infuriating! — Ashleigh Tuffney (@ashleightuff) June 27, 2022 loadshedding is quite damaging to the electrical infrastructure and it shows in the insane power outages happening in all the areas post loadshedding 😒😒😒 and city power is extremely incompetent at fixing it fast enough meaning some people are going days without electricity. — jannat jalebi 🍭🥨 (@tasmiyahhhhh) June 26, 2022 Stage 4 is just nonsense nje, constant power outages when power is supposed to be restored back, also working remotely is so hard, ngapha there is the petrol Pandemic 😩😩 #Loadshedding — Tha🐝 (@Rethabile_05) June 27, 2022 Energy analyst and electrical engineer Chris Yelland explained to Daily Maverick that in a city like Joburg — or any large city — urbanisation and rising population increased the demand for electricity, which ramped up pressure on the circuits. “Levels of housing density are constantly increasing and therefore the electricity consumption is increasing over time,” said Yelland, adding that non-payment (which is escalating as the price of electricity goes up) also puts pressure on the system. Mangena said increased demand due to winter weather, rampant cable theft and illegal connections also added pressure to an already overstretched system. Now, all this — coupled with load shedding — causes circuit breakers to trip, resulting in mass outages in Joburg. Yelland uses the example of water geysers, explaining that when there’s load shedding and the power is turned off for two hours in an area, all the geysers in the neighbourhood begin cooling down. When the power returns, all those geysers switch on simultaneously, sucking up energy to reach the temperature set by the thermostat. “And that might be enough to push you over the limit of the circuit breakers,” said Yelland. So once the power comes online, the current is higher than normal, which trips the circuit breaker. Someone has to physically go to the substation to close the circuit breaker, and there is already limited manpower, which causes delays in getting the power back. Mangena said that “apart from the lost revenue during load shedding, we are also forced to pull technicians and operators from leave, and many are already fatigued”. “We are also forced to divide our resources between attending to outage calls and responding to the two-hourly load shedding switch on and offs.” Mangena said they are “beefing up resources in our service delivery centres, with more operators added to ensure we respond in time with limited delays during restorations”. He said that for safety reasons, no maintenance was done during load shedding. “It’s all to do with the fact that the circuit breakers are running close to their rated value because of urbanisation, increasing population density, increasing electricity usage… and load shedding,” said Yelland. “Which might be the final thing that causes you to push above the limit.” Mangena said that in-rush currents, multiple cable faults, vandalism and overloading due to the cold weather are among the reasons for the trippings in most areas, especially after load shedding restorations. Poorly managed and ageing infrastructure Mangena said “our mostly ageing infrastructure also cannot be ignored, and its wear and tear increases every time they are switched on and off at short intervals”. Yelland said that if we had well-maintained, relatively new equipment, switching on and off regularly shouldn’t be an issue. “When you have old equipment that is under-maintained — with the oil in the transformers not clean, the insulation weakened with temperature and time, and moisture getting into the cables and into the joints and into the switchgear — you’ll find that that switchgear is weakened… the cables are weakened.” This means that frequent switching causes critical damage to that equipment, which can result in system failures. “That’s just a sign of an ageing, poorly maintained network,” said Yelland. “Which is exactly what we have in South Africa in many, many municipalities.” Councillor Beverley van Reenen, Mayoral Committee Member for Energy, City of Cape, said: “The City of Cape Town's infrastructure is generally well maintained and maintained to the required standards. It is thus not the reason for secondary tripping. “Among the main reasons for extended outages after load shedding in City-supplied areas are as follows: Secondary tripping in some pockets of larger areas mostly occur due to excessive demand. When power comes back on, tripping happens as electrical equipment such as geysers all come on at the same time, not having been switched off prior to load shedding. “In addition, vandalism under the cover of load shedding is an increasingly common phenomenon as criminals strip substations and kiosks. These actions cause outages. “Lastly, switching stations were not designed for load shedding. Most of the switching in City-supplied areas is done remotely and upgrades to switching station equipment continues to ensure the timeous switching during load shedding.” Eskom strikes threaten Stage 8 On Sunday, Eskom announced that Stage 4 load shedding is anticipated to continue until at least midnight on Wednesday due to “unlawful and unprotected labour actions” at several power stations, which have caused delays in carrying out planned maintenance and repairs. Business Maverick reported that thousands of Eskom employees had been striking and protesting after wage talks deadlocked last Tuesday. As Eskom is deemed an “essential service”, the strike is unprotected — which means workers who down tools can be fired. Union sources and Eskom confirmed to Business Maverick on Monday that the strikes and protests were continuing. Eskom says this illegal strike is putting about 4,000MW of generation capacity at risk. Yelland said that if we lose another 4,000MW, SA is at risk of Stage 6 to Stage 8 load shedding. He explained that 4,000MW is four stages of load shedding, since each stage is 1,000MW. Eskom says 4000 MW of generation capacity is at risk due to industrial action. Before the industrial action we had Stage 2 to Stage 4 loadshedding. Now there is an additional 4000 MW (4 stages of loadshedding) at risk. So, we are now at risk of Stage 6 to Stage 8 loadshedding. https://t.co/Q3tFjwEAA9 — Chris Yelland (@chrisyelland) June 26, 2022 Mangena said that “with Eskom’s unprotected strike seemingly far from over, we are in fact preparing for the worst...” He urged customers to switch off heavy appliances during load shedding. “This include geysers, pool pumps, heaters, stoves. These can be switched back on, gradually, a few minutes after restorations.” DM/OBP

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Power supply on a knife edge, says EskomSouth Africans can brace for even greater load-shedding misery this week if Eskom suffers another major breakdown this weekend as a pay strike adds to the utility's woes. What is even disappointing is the guys can't even say how many are striking. You can't have 1% of your workforce cause havoc to the entire system. They are using the striking workers as scapegoats they are working this along crypo money landering at the same bitcoin time as eskom , almost same hours

OPINIONISTA: Wanted: A real emergency energy plan – yesterdayLoad shedding will get even worse, unless we implement an emergency plan to roll out renewable energy and storage, and appoint a new energy minister capable of delivering. Yep. GwedeMantashe1 is out of his depth and compromised We don't need a new minister of energy, we need a completely new, capable and competent government. South Africans must return to a culture of paying for the electricity and water they use. Municipalities must likewise pay the same utility companies. This, and having government with integrity (not stealing or wanting bribes to do their jobs) that makes a country successful.

Eskom extends Stage 4 load-sheddingEskom has announced that it will extend Stage 4 load-shedding into next week.

Load-shedding to continue at stage 4 until Wednesday or longerStage 4 load-shedding will continue until Wednesday. Thank you to the striking Eskom employees Come Wednesday, extended till Sunday 😂😭 Professional bullshiters! 🚮🚮🚮🚮

Load-shedding to continue at stage 4 until Wednesday or longerStage 4 load-shedding will continue until Wednesday.

Eskom power cuts delay repairs of overloads and faults caused by load-sheddingFault repairs after scheduled power cuts are often interrupted by further load-shedding. Lol Time to privatize electricity, at this rate the whole country is going down the drain with Eskom… Eskom is selfish and greedy

Pushing the limits: Why load shedding puts even more pressure on an ageing electrical system by Julia Evans, Daily Maverick June 27, 2022 Pushing the limits: Why load shedding puts even more pressure on an ageing electrical system by Julia Evans, Daily Maverick June 27, 2022 Johannesburg's power utility City Power's ageing infrastructure is not coping with the demands of Stage 4 load shedding..of the 2,000MW the program was supposed to deliver.that Stage 4 load-shedding will continue next week from 05:00 to midnight until Wednesday, 29 June 2022.

Communicating with residents through a ward WhatsApp group, Nicolene Jonker, DA councillor in the City of Johannesburg, told residents on Monday that “City Power can’t cope with Stage 4 load shedding. Half the operators are busy switching load centres on and off every two hours for load shedding, and the number of substation trips from inrush current after load shedding is very high. This article is reserved for Sunday Times subscribers.” Isaac Mangena, spokesperson for City Power Joburg agreed with her assessment, telling Daily Maverick that Stage 4 was putting too much strain on their resources, with some substations unable to return during restorations, leaving customers without power for a longer period. So, by the time the new solar projects come online, they will only meet around 3% of the current energy supply gap and 0. “Load shedding has undesirable effects on the infrastructure which, by its nature, was never meant to be switched on and off at short intervals, and comes with it added financial pressures that we did not budget for,” said Mangena. Already subscribed? Simply sign in below. Mangena said that at the weekend they fielded more than 5,000 outage calls and by 6am on Monday, they were dealing with almost 2,700 calls — more than 2,000 of them in 24 hours. The power utility currently has 3,894MW of generating capacity offline for scheduled maintenance, with a further 15,472MW unavailable due to breakdowns.

Most of the outages have been backlogged since Friday, with Randburg, Reuven and inner-city areas hit the hardest most of last week and into the weekend.. Apart from being snared in legal and environmental challenges, the polluting powerships are also proving to be uneconomic , especially with gas prices so high and so volatile. Residents have taken to social media to express their frustration and confusion about why they still do not have electricity outside scheduled load shedding. Ok now it’s 16:40 and still@no power after loadshedding? After our 6 hour outage this morning. Loadshedding is ridiculous enough as it is and even it doesn’t work properly. Whatever the motivation, the result is that we have a stalled emergency energy program that may never see the majority of its proposed projects come to light. Absolutely infuriating! — Ashleigh Tuffney (@ashleightuff) June 27, 2022 loadshedding is quite damaging to the electrical infrastructure and it shows in the insane power outages happening in all the areas post loadshedding 😒😒😒 and city power is extremely incompetent at fixing it fast enough meaning some people are going days without electricity. “We appeal to all South Africans to help limit the impact of the shortages by continuing to reduce the usage of electricity and to switch off all non-essential items.

— jannat jalebi 🍭🥨 (@tasmiyahhhhh) June 26, 2022 Stage 4 is just nonsense nje, constant power outages when power is supposed to be restored back, also working remotely is so hard, ngapha there is the petrol Pandemic 😩😩 #Loadshedding — Tha🐝 (@Rethabile_05) June 27, 2022 Energy analyst and electrical engineer Chris Yelland explained to Daily Maverick that in a city like Joburg — or any large city — urbanisation and rising population increased the demand for electricity, which ramped up pressure on the circuits. “Levels of housing density are constantly increasing and therefore the electricity consumption is increasing over time,” said Yelland, adding that non-payment (which is escalating as the price of electricity goes up) also puts pressure on the system. Even before it was written, the IRP was out of date. Mangena said increased demand due to winter weather, rampant cable theft and illegal connections also added pressure to an already overstretched system. Now, all this — coupled with load shedding — causes circuit breakers to trip, resulting in mass outages in Joburg. Yelland uses the example of water geysers, explaining that when there’s load shedding and the power is turned off for two hours in an area, all the geysers in the neighbourhood begin cooling down. That is, if they ever get built in the face of.

When the power returns, all those geysers switch on simultaneously, sucking up energy to reach the temperature set by the thermostat. “And that might be enough to push you over the limit of the circuit breakers,” said Yelland. So once the power comes online, the current is higher than normal, which trips the circuit breaker. Someone has to physically go to the substation to close the circuit breaker, and there is already limited manpower, which causes delays in getting the power back. Mangena said that “apart from the lost revenue during load shedding, we are also forced to pull technicians and operators from leave, and many are already fatigued”.

“We are also forced to divide our resources between attending to outage calls and responding to the two-hourly load shedding switch on and offs.” Mangena said they are “beefing up resources in our service delivery centres, with more operators added to ensure we respond in time with limited delays during restorations”. He said that for safety reasons, no maintenance was done during load shedding. “It’s all to do with the fact that the circuit breakers are running close to their rated value because of urbanisation, increasing population density, increasing electricity usage… and load shedding,” said Yelland. “Which might be the final thing that causes you to push above the limit.

” Mangena said that in-rush currents, multiple cable faults, vandalism and overloading due to the cold weather are among the reasons for the trippings in most areas, especially after load shedding restorations. Poorly managed and ageing infrastructure Mangena said “our mostly ageing infrastructure also cannot be ignored, and its wear and tear increases every time they are switched on and off at short intervals”. Yelland said that if we had well-maintained, relatively new equipment, switching on and off regularly shouldn’t be an issue. “When you have old equipment that is under-maintained — with the oil in the transformers not clean, the insulation weakened with temperature and time, and moisture getting into the cables and into the joints and into the switchgear — you’ll find that that switchgear is weakened… the cables are weakened.” This means that frequent switching causes critical damage to that equipment, which can result in system failures.

“That’s just a sign of an ageing, poorly maintained network,” said Yelland. “Which is exactly what we have in South Africa in many, many municipalities.” Councillor Beverley van Reenen, Mayoral Committee Member for Energy, City of Cape, said: “The City of Cape Town's infrastructure is generally well maintained and maintained to the required standards. It is thus not the reason for secondary tripping. “Among the main reasons for extended outages after load shedding in City-supplied areas are as follows: Secondary tripping in some pockets of larger areas mostly occur due to excessive demand.

When power comes back on, tripping happens as electrical equipment such as geysers all come on at the same time, not having been switched off prior to load shedding. “In addition, vandalism under the cover of load shedding is an increasingly common phenomenon as criminals strip substations and kiosks. These actions cause outages. “Lastly, switching stations were not designed for load shedding. Most of the switching in City-supplied areas is done remotely and upgrades to switching station equipment continues to ensure the timeous switching during load shedding.

” Eskom strikes threaten Stage 8 On Sunday, Eskom announced that Stage 4 load shedding is anticipated to continue until at least midnight on Wednesday due to “unlawful and unprotected labour actions” at several power stations, which have caused delays in carrying out planned maintenance and repairs. Business Maverick reported that thousands of Eskom employees had been striking and protesting after wage talks deadlocked last Tuesday. As Eskom is deemed an “essential service”, the strike is unprotected — which means workers who down tools can be fired. Union sources and Eskom confirmed to Business Maverick on Monday that the strikes and protests were continuing. Eskom says this illegal strike is putting about 4,000MW of generation capacity at risk.

Yelland said that if we lose another 4,000MW, SA is at risk of Stage 6 to Stage 8 load shedding. He explained that 4,000MW is four stages of load shedding, since each stage is 1,000MW. Eskom says 4000 MW of generation capacity is at risk due to industrial action. Before the industrial action we had Stage 2 to Stage 4 loadshedding. Now there is an additional 4000 MW (4 stages of loadshedding) at risk.

So, we are now at risk of Stage 6 to Stage 8 loadshedding. https://t.co/Q3tFjwEAA9 — Chris Yelland (@chrisyelland) June 26, 2022 Mangena said that “with Eskom’s unprotected strike seemingly far from over, we are in fact preparing for the worst...

” He urged customers to switch off heavy appliances during load shedding. “This include geysers, pool pumps, heaters, stoves. These can be switched back on, gradually, a few minutes after restorations.” DM/OBP This article first appeared on Daily Maverick and is republished here under a Creative Commons license. Copy to Clipboard .