South Africa faces the need to diversify its energy mix and reduce its reliance on fossil fuels as part of the transition towards a more sustainable future. Energy storage systems (ESS) play a critical role in supporting this energy transition, but South Africa is yet to realize its full potential. As the energy transition progresses, the financial and sustainability considerations of new ESS use cases become paramount. While extensive research explores different ESS technology options, a crucial knowledge gap remains in understanding how to best adapt ESS use cases to South Africa’s unique energy landscape. Rather than focusing on technology options for optimal ESS selection, this paper introduces the perspective of value stacking by considering the technical requirements of ESS use cases. Key findings of this study include potential emerging use cases such as the procurement of seasonal energy and the importance of capacity firming as well as ancillary service use cases such as reserves and frequency regulation. Potential value stacking use cases are identified using a comparative analysis and use case technical requirements. This research provides insights for policymakers, energy providers, and stakeholders navigating the financial implications of integrating energy storage into South Africa’s evolving energy sector.