Cape Town’s “battery” that protects residents against worsening power cuts

Premier Alan Winde took his 23rd Energy Digicon into the heart of one of the City of Cape Town’s most effective “weapons” against the energy crisis, the Steenbras Pumped Storage Station. He was joined by the Executive Mayor of Cape Town, Alderman Geordin Hill-Lewis.

Before proceedings got under way, Premier Winde offered his deepest condolences to the families and loved ones of those who died in the devastating building fire in the Johannesburg city centre this week. “A tragedy on this scale is heart-wrenching and here in the Western Cape we feel the pain of those who have suffered from this disaster. We at the Western Cape Government stand ready and willing to help the City of Johannesburg, its emergency services, and the Gauteng Provincial Government should they need it.”

While the Digicon started on a somber note, once it got going, it was very clear how excited Premier Winde and the team were to visit this important site. Depending on the lower dam levels, Steenbras Pumped Storage Station can protect Cape Town residents, businesses, and the city’s economy from one or two stages of loadshedding. “I want to celebrate the team that keeps this facility running and in tip-top shape. That is the difference between this power station and so many other stations in South Africa. It is well looked after. This plant is maintained on a continuous basis,” said Mayor Hill-Lewis.

“At the moment we are preparing for two upgrades at Steenbras. The City is preparing a study on how we can expand the size of the lower dam to increase storage capacity as well as preparing for a major refurbishment in 2027. Expanding the size of the lower dam would increase the storage space available which would mean that we could protect the City from even more stages of load shedding,” remarked the Mayor.

“Steenbras is so much more than just a dam. As important as it is in collecting and storing water, during mass power cuts it also acts as a massive battery which helps mitigate the worst of load shedding. I am very impressed at how well this facility is managed and I applaud the City of Cape Town and the team that runs the station for the hard work they put into maintaining this crucial facility,” said Premier Winde.

Mr Phillip Eybers, the station’s Manager for Mechanical Maintenance, explained how the hydro-electric station functions:

• When power cuts kick in water from the upper dam is released into the lower dam, generating up to 160 MW of power through its pumped storage hydroelectric system.
• When electricity usage drops, overnight, the turbines pump water back to the upper dam to be reused over peak hours in the daytime.
• Maintenance of the station is a top priority. Mr Eybers said, “This is the primary reason why the station is still able to operate beyond its original design.”

In his regular update on the status of the power grid, Special Advisor to the Premier on Energy, Mr Alwie Lester, compared the amount of electricity that was available in 2022 with 2023, which included Eskom’s installed base and contracted generation. Around mid-2022, almost 33 000 MW was dispatched into the national power system. “In 2023, at exactly the same time of the year, if you look at what was available to us and what we could dispatch, we were only able to dispatch just under 28 000 MW. There is a significant drop in the availability of energy. We are consistently between 4 000 and 5 000MW below where we were a year ago. This is concerning. It will impact decisions around investment and development. If the energy is not available, they (businesses and investors) will not make those kinds of decisions very quickly,” said Mr Lester.