Eskom is focused on modernising its distribution network, ensuring equitable grid access and prioritising end consumers. Battery energy storage systems (BESS) are central to this effort, playing an important role in stabilising South Africa’s evolving grid and facilitating the shift towards a decentralised energy market as the country’s electricity sector undergoes unbundling and democratisation.

This is according to Malcolm van Harte, Eskom’s General Manager: Distribution Strategy, speaking at the Energy Intensive Users Group of Southern Africa (EIUG) conference alongside the inaugural C&I Solar and Storage conference in Johannesburg yesterday, November 19.

Eskom will oversee the management of its network while implementation of inverter-based technology will be combined with BESS, he said. “With the introduction of renewables, we need ancillary services like voltage control and peak shifting to ensure security and reliability of supply. We no longer talk about load or generation; we talk about flexible demand, flexible load and a flexible supply option. This is where BESS will play a vital role.”

South Africa’s electricity distribution industry is lagging because of insufficient policy decisions. To meet future customer needs, Eskom is reimagining its distribution strategy and preparing the grid for the demands of a decentralised energy market, Van Harte said. “The grid is key. We need to prepare the grid for the future.

“While the National Transmission Company of South Africa has promised to create a ‘super highway’ for a democratised energy market, the truth is we don’t have the ‘roads’ to get onto the superhighway.”

Over the past 10 years, the country has invested in power generation while neglecting distribution infrastructure. This has created gaps in the system's ability to deliver electricity effectively, according to Van Harte. The situation has been further complicated by consumers becoming power generators, which fundamentally changes management of the power system. Eskom aims to achieve a win-win situation where the voltage and the power system can still be effectively controlled, he said.

“We no longer think of the power system as passive where electrons flow in just one direction. Instead, it is now an active system. With the inclusion of distributed energy resources, we must reconsider how we manage the power grid. Energy storage plays a crucial role in balancing supply and demand.”

With South Africa’s water scarcity limiting hydropower potential and system operators exploring alternatives like synchronous condensers, Van Harte described BESS as the most practical and scalable solution. “If we do not adopt batteries and continue to integrate more renewable energy into the grid, we will create power quality challenges. BESS is integral to congestion management, voltage stability, power quality and grid resilience.”

Eskom has already made headway in its BESS rollout, commissioning key projects such as the 40 MW Pongola and 80 MW Skaapvlei sites. Looking ahead, the utility plans to partner with aggregators to integrate storage solutions under the distribution system operator’s control, Van Harte said.