Cape Town – While some may have been getting used to Stage 2 and Stage 4 load shedding, it many people will have to prepare for Stage 5 and Stage 6.
Since Monday, South Africans have been subjected to frequent changes in load shedding stages, with Eskom moving the country from Stage 2 to Stage 3, then Stage 4, and now to Stage 6.
Stage 4 was in place on Wednesday morning, but Eskom then announced that it had implemented Stage 6 load shedding from midday.
It said this was due to a high number of breakdowns since midnight, as well as the need to preserve the remaining emergency generation reserves.
While the rest of the country would be under Stage 6 load shedding, the City of Cape Town said it would protect its customers who would only face Stage 5 load shedding during this time.
Urgent load-shedding update - 7 December
— City of Cape Town (@CityofCT) December 7, 2022
Eskom moves to Stage 6 from 12:00.
City customers
7 December
Stage 5: 12:00 until further updates
The City continues to protect its customers as far as possible.#CTInfo pic.twitter.com/pzf8wEkIZ4
In a press briefing on the state of Eskom last month, the power utility’s chief operating officer Jan Oberholzer said the Koeberg power station would be subject to scheduled maintenance from early December until June next year – in the final stretch of Eskom’s preparations to extend the plant’s life beyond 2024.
As a result, there will be more load shedding, Eskom executives have warned.
Mayoral committee (Mayco) member for energy Beverley van Reenen had explained that earlier that “where possible, the City has been able to protect its customers from up to two stages of load shedding primarily through the management of the Steenbras Hydro Pump Station”.
The 180-megawatt Steenbras Hydro Pump Station consists of four turbines that are used to generate electricity. During peak electricity demand, it channels water from Upper Steenbras to Lower Steenbras, through the turbine generator, to create electricity.
When electricity usage is low, usually from 11pm to 7am, the turbines pump the water back to the Upper Steenbras Dam to be reused the next day. In this way, Steenbras Hydro Pump Station operates like a battery.
The amount of electricity that it can generate in one day is limited by the capacity of the lower reservoir.
“Thus about two-thirds of the water used to generate power during the day is pumped back at night to the upper Steenbras reservoir to create more space for continual utilisation of the power station.
“It’s more like charging the cellphone battery at night for usage during the following day. Cape Town is the only city in South Africa to own and operate a large pumped hydroelectric scheme,” Van Reenen said.
Adding that through its excellent and diligent maintenance of this critical and complex infrastructure, the City of Cape Town could help protect customers from the highest Eskom tariffs, as well as from up to two stages of load shedding.
Van Reenen also said that at higher Eskom load shedding stages, the City garners energy from the use of gas turbines during the evening peaks between 5pm and 8pm, to bolster the capacity of the Steenbras-generated reserves.
“This is used at the high stages of load shedding where possible. It is very important for the City to safeguard critical infrastructure for service delivery to all, as well as to protect its electricity network,” she said.
“The City manages its infrastructure and power generation and distribution well to ensure reliable supply within its powers. We will keep doing what it is doing well and look to innovations to enhance mitigation and protection and build Cape Town’s resilience.
“We will continue to do all we can to protect customers from load shedding where it can, while at the same time working to end load shedding over time.”