Holding Its Own Customers Below the National Load-Shedding Stage
Cape Town owns Steenbras, a pumped-storage scheme built in 1979 in the mountains above Gordon's Bay, and from June 2015 used it to hold its own electricity customers one stage below the national load-shedding stage — occasionally two, and at times none at all, which the City labelled Stage 0. The mechanism is dispatch, not sensing: four reversible turbines run through the evening peak and pump the water back overnight, shaving enough demand that the City can shed less than Eskom orders. Protection was never guaranteed. It collapsed at Stage 6, and weekends went on rebuilding the reservoir for the week ahead. It also stopped at the City's billing boundary: Cape Town distributes roughly 70 percent of the metro's electricity, Eskom supplies the rest directly, and those customers cannot be protected. Eskom rejected the City's 2023 bid to buy out those supply areas. An independent synthetic-control study found the policy significantly reduced deaths — and that the protected areas hold 81 percent of the city's white residents but 27 percent of its black African residents. No national load-shedding has occurred since 15 May 2025; the scheme stays in service under a R1.2bn refurbishment.
City of Cape Town figures (self-reported): about 514 hours, roughly 21 days, of one-stage protection for City-supplied customers between January and May 2022; Stage 4 held for City customers while Eskom ran Stage 6 nationally in June 2022. Independent estimate (Joshua Budlender, UNU-WIDER working paper 2024-44, stacked synthetic control): about 547 premature deaths averted among City-supplied residents aged 65 and over, 2015-2019, 95% confidence interval 94 to 1,002 — the author stresses the estimate is imprecise. Same study: 81% of Cape Town's white residents live in the protected City-supplied areas, against 27% of its black African residents.
🎓 Lesson
One dispatchable asset the city already owned bought a stage of relief that measurably saved lives — but nothing about it was smart, and the relief followed apartheid-era supply lines rather than need. Pumped storage also consumes more grid power than it returns; Cape Town shifted Eskom's electricity in time, it never made any.
Evidence📊 Independent
Scale🏙️ City-wide
Cost≈R1.2bn budgeted in 2023 for Steenbras: about R1bn refurbishment and expansion plus about R200m maintenance over nine years
FundingCity of Cape Town capital budget
Sources
↗ UNU-WIDER: Surviving in the Dark (WP2024-44)Fetched. Joshua Budlender, July 2024. Abstract: 'the introduction of a unique load shedding reduction policy in parts of South Africa's second-largest city'. Confirms the policy statistically significantly reduces mortality and that 'the incomplete geographic coverage of the mitigation policy entrenches existing inequalities in the city'. The page states explicitly that this is a working paper, not peer-reviewed — hence evidence graded independent, not peer-reviewed.
↗ SALDRU, University of Cape Town (academic summary)Fetched. Author's home institution summarising the paper: synthetic control across the 2015, 2018 and 2019 mitigation episodes; Steenbras used to mitigate load shedding since June 2015 — the source for yearStart; 547 deaths averted, 95% CI 94-1,002; mitigation covered about 73% of the City's 65+ population; mortality data from the SA Medical Research Council, load-shedding data from the City and EskomSePush.
↗ UNU-WIDER blog: A tale of two citiesFetched. Sole verified source for the 81% white / 27% black African split between protected and unprotected areas, and for the author's framing of it as a legacy of apartheid-era urban planning.
↗ Daily Maverick, 30 June 2022 (press)Fetched. 180 MW, four turbines, City owns and operates it, only South African city to do so; Stage 4 held while Eskom ran Stage 6 in June 2022; 514 hours or 21 days of one-stage protection January to May 2022 (City figures); analyst Chris Yelland on fast hydro ramping and on why other municipalities cannot copy it.
↗ Engineering News, 18 April 2023 (trade press)Fetched. R1bn refurbishment plus R200m maintenance over nine years; Energy MMC Beverley van Reenen on protecting 'a stage or two, where possible' and the plan to reach four stages. Note the capacity discrepancy: this source and most City statements say 160 MW (available output), the plant record says 180 MW nameplate.
↗ Daily Maverick / Bloomberg, 25 May 2023 (press)Fetched. The 70/30 City-Eskom supply split; protection of about two stages applies to City-supplied zones only; Mayor Geordin Hill-Lewis, 'We want to supply the entire city'; the takeover talks Eskom later declined.
↗ Steenbras Power Station (plant record)Fetched. Used only for plant specification: 4 x 45 MW reversible turbines, 180 MW installed, commissioned 1979, owned and operated by the City of Cape Town Electricity Department. Low-authority source, cited only for specification, and its claim of being Africa's first pumped-storage scheme was NOT used — single weak citation.
↗ Crown Publications, 21 May 2026 (trade press)Fetched. Currency check: last national load-shedding 15 May 2025; at 00:01 on 16 May 2026 Eskom had gone one full year without it, the first since September 2018. Basis for status live but function dormant, outcome ongoing. Eskom's own milestone page returned HTTP 403 to automated fetching.
↗ City of Cape Town: How it works — City and Eskom electricity supply areasFETCH FAILED — capetown.gov.za returned HTTP 502 to every automated request across three attempts, and its load-shedding FAQ PDF could not be parsed. Listed as the authoritative municipal statement of the supply split; every fact drawn from it here is instead carried by the independently fetched Bloomberg and UNU-WIDER sources.
📎 Cite this project
1001 Smart Cities (2026). “Holding Its Own Customers Below the National Load-Shedding Stage” — Cape Town, South Africa. The Smart City Atlas. https://1001smartcities.org/projects/cape-town-load-shedding-protection/ (last verified 2026-07-26). Data: CC BY 4.0.
The underlying data is free to reuse with attribution — see the open data page.
