Watts in Store Part 1: Explainer on how energy storage can help South Africa’s electricity crisis

The document argues that while consumer-led battery deployment is rapid, grid-scale energy storage—particularly batteries—is a strategic priority that remains under-developed in South Africa. It details how storage can reduce load shedding, optimize existing grid infrastructure, and support a just energy transition by providing public benefits. The authors recommend the development of national and municipal strategies to create an enabling environment for grid battery deployment.

• South Africa's electricity crisis is driven by the declining performance of Eskom's aging coal fleet and significant transmission grid constraints, particularly in the Cape region, which prevent the connection of new utility-scale renewable energy projects.
• Consumer-located energy storage, often paired with solar PV, is being deployed rapidly and uncoordinatedly, which helps reduce demand from the grid but can create demand spikes if batteries recharge immediately after load shedding ends.
• Grid-located energy storage provides seven key benefits: reducing demand for grid supply, smoothing out load shedding, improving power plant utilization, enabling new utility-scale renewables, optimizing existing grid use, deferring network expansion, and contributing to a just energy transition.
• Battery Energy Storage Systems (BESS) are identified as an immediate strategic priority due to their rapid deployment times, falling costs, and versatility compared to pumped hydro or concentrated solar power (CSP).
• Despite their importance, grid storage projects in South Africa have lacked momentum and are frequently delayed, including the Tubatse pumped hydro scheme and various IRP 2019 and Eskom BESS targets.
• Pumped hydro remains a complementary technology for long-duration storage, but its long construction times (averaging 8 years for Eskom schemes) make it unsuitable for short-term crisis relief.
• The report emphasizes that grid storage aligns better with Just Energy Transition (JET) principles than consumer storage, as the latter may shift the cost of grid maintenance onto low-income populations who cannot afford their own systems.
• Current power system modelling for South Africa indicates that all new grid storage capacity through 2030 will likely be in the form of batteries, with durations typically ranging from 1 to 4 hours.

APA

Halsey, R., Bridle, R., & Geddes, A. (2023). Watts in Store Part 1: Explainer on how energy storage can help South Africa’s electricity crisis. International Institute for Sustainable Development. https://www.iisd.org/system/files/2023-07/south-africa-watts-in-store-part-1.pdf

Chicago

Halsey, Richard, Richard Bridle, and Anna Geddes. Watts in Store Part 1: Explainer on how energy storage can help South Africa’s electricity crisis. International Institute for Sustainable Development, 2023. https://www.iisd.org/system/files/2023-07/south-africa-watts-in-store-part-1.pdf.

Wikipedia

{{cite report |last1=Halsey |first1=Richard |last2=Bridle |first2=Richard |last3=Geddes |first3=Anna |title=Watts in Store Part 1: Explainer on how energy storage can help South Africa’s electricity crisis |publisher=International Institute for Sustainable Development |date=June 2023 |url=https://www.iisd.org/system/files/2023-07/south-africa-watts-in-store-part-1.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{halsey2023watts, author = {Halsey, Richard and Bridle, Richard and Geddes, Anna}, title = {{Watts in Store Part 1: Explainer on how energy storage can help South Africa’s electricity crisis}}, institution = {International Institute for Sustainable Development}, year = {2023}, month = jun, url = {https://www.iisd.org/system/files/2023-07/south-africa-watts-in-store-part-1.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }