- Eskom and Energy Vault to deploy first 100MWh gravity energy storage project at Hendrina Power Station in Mpumalanga.
- Partnership targets deployment of up to 4GWh of long duration energy storage across 16 SADC countries by 2035.
- Project supports South Africa’s Just Energy Transition through grid stability, coal ash recycling and local job creation.
Energy Vault and Eskom have signed a Strategic Development Agreement to deploy grid scale gravity energy storage systems in South Africa, marking a major step in the region’s transition toward cleaner and more reliable energy infrastructure.
The first project under the agreement will be developed at Eskom’s Hendrina Power Station in Mpumalanga, one of South Africa’s oldest coal fired power plants. The facility will deploy a gravity energy storage system with a capacity of 25MW and four hours of storage, equivalent to 100MWh. The system has been designed for scalability and forms part of a broader long duration energy storage pipeline targeting up to 4GWh across the Southern African Development Community region by 2035.
Under the agreement, Energy Vault will provide its EVx 2.0 gravity energy storage technology together with engineering support, project management and localised training services. The companies also plan to co develop and license the technology across the 16 member SADC bloc.
The EVx 2.0 platform uses gravity based storage technology that lifts and lowers heavy composite blocks to store and discharge electricity. The latest version incorporates improvements in software orchestration, mechanical operations, construction automation and energy efficiency, enabling deployment at multi gigawatt scale.
A key feature of the project is the use of coal ash waste as part of the composite material used in the storage blocks, which can weigh between 25 and 30 tonnes each. The approach is expected to support circular economy objectives by repurposing waste from coal fired generation facilities.
One of Eskom’s oldest coal fired power stations, Hendrina, is located approximately 40km south of Middelburg at the town of Hendrina in Mpumalanga, South Africa. At the time it was built in the early 70″s it was the largest power station in the country with a generating capacity of 2000MW. It is now well passed its sell-bye date. South Africa’s coal fired power stations are breaching minimum emissions standards but shutting them down may jeopardise energy supply. Image credit: Eskom
Robert Piconi, Chairman and Chief Executive Officer of Energy Vault, said the agreement represents a major milestone for both the company and Africa’s energy transition ambitions.
He said the partnership combines Energy Vault’s gravity storage technology with Eskom’s power generation and grid expertise to accelerate the deployment of long duration energy storage across Southern Africa.
Piconi added that the initiative will help create local jobs, strengthen regional supply chains and support the shift from coal dependence toward a more resilient and secure energy system.
The partnership aligns with Eskom’s Just Energy Transition Partnership strategy, which aims to reduce emissions while supporting economic development and grid reliability.
Dan Marokane, Group Chief Executive of Eskom Holdings, said the utility remains committed to lowering the environmental impact of its generation fleet while ensuring a responsible and inclusive energy transition.
He said Eskom’s long term strategy includes repowering and repurposing coal fired power stations while exploring new clean energy technologies that can improve operational efficiency and reduce electricity costs.
Southern Africa continues to expand electricity access and diversify its energy mix as countries across the SADC region seek to improve energy security. Electricity access across the region has increased from 36% a decade ago to 56% today. Despite this progress, coal still accounted for more than 80% of South Africa’s electricity generation in 2024.
Utility scale energy storage is expected to play a critical role in supporting renewable energy integration, strengthening grid resilience and improving power reliability across the region. The Eskom and Energy Vault partnership positions both companies at the forefront of long duration energy storage deployment in Africa.
Author: Bryan Groenendaal
