South Africa’s state-owned electricity utility Eskom has signed a Strategic Development Agreement with Energy Vault Holdings, Inc. to deploy a long-duration Gravity Energy Storage System (GESS) at its power stations.
The companies announced plans to deploy the first gravity storage system at the Hendrina Power Station in Mpumalanga Province, South Africa, with the intention to license, co-develop, and collaborate on the deployment of up to 4GWh of long-duration energy storage across the 16 member states of the Southern African Development Community (SADC).
The partnership is expected to significantly advance regional efforts to transition away from coal while leveraging advanced material science technology for the economic re-use of waste coal ash within the energy storage medium. The initiative is also aimed at improving grid reliability, creating jobs, and supporting local economic development.
Eskom said the first GESS plant will be built at its Hendrina Power Station in Mpumalanga, one of the utility’s oldest operating stations.
The system is expected to provide 25MW of capacity with four hours of storage, equivalent to 100MWh, and is designed to be fully scalable up to 4GW. The landmark agreement establishes a long-term partnership between the two companies to accelerate the decarbonization of Southern Africa’s power sector.
Under the terms of the agreement, Energy Vault will provide Eskom with its latest EVx 2.0™ GESS technology system and associated equipment, along with on-site engineering, project management, and localized training support.
The partnership intends to license, co-develop, and collaborate on the deployment of up to 4GWh of GESS storage, with significant potential across the 16-member SADC region by 2035.
Energy Vault’s EVx 2.0™ GESS platform incorporates major advancements over the previous EVx design, particularly in software orchestration, mechanical operation, energy efficiency, construction automation, and construction tooling.
These enhancements enable a system capable of scaling to multi-gigawatt energy storage capacity to support increasing renewable energy penetration.
The EVx 2.0 design also features improved material science technology for the economic re-use of ash from coal combustion as the storage medium in the blocks, which may weigh up to 25–30 tons each.
Commenting on the partnership, Robert Piconi said:
“This landmark agreement with Eskom represents a transformational milestone for Energy Vault and for Africa’s energy future.
“By combining our breakthrough EVx 2.0 platform with Eskom’s extensive power generation, grid expertise, and regional reach, we are not only advancing long-duration storage at unprecedented scale but also pioneering a new model for sustainable industrial development.
“This partnership will create local jobs, establish resilient supply chains, and demonstrate how gravity energy storage can accelerate Africa’s transition from coal dependency to energy independence and security — while delivering reliable, affordable power to communities that need it most.”
Dan Marokane emphasized that the collaboration directly supports Eskom’s Just Energy Transition Partnership (JETP) initiative, which focuses on achieving a sustainable and equitable transition away from coal while ensuring grid reliability, job creation, and local economic development.
He said Eskom will drive a just and inclusive energy transition by intensifying the repowering and repurposing of coal power stations while exploring clean coal technologies and solutions that use technology as a strategic enabler to improve efficiencies and lower electricity costs.
According to him, Eskom’s partnership with Energy Vault and its innovative gravity storage technology will play a pivotal role in achieving the utility’s Just Energy Transition goals.
Southern Africa is undergoing a significant transformation in its energy landscape, with governments and utilities across the SADC region working to expand access to reliable, affordable, and sustainable electricity.
“Today, 56% of the SADC region’s population has access to electricity, up from just 36% a decade ago, reflecting the impact of coordinated regional efforts and investment in infrastructure. Coal remains the dominant source of power generation, contributing over 80% of South Africa’s electricity supply in 2024, but the region is actively diversifying its energy mix. Utility-scale energy storage technologies are set to play a key role in integrating renewables, strengthening national grid resilience, and improving grid reliability — while also unlocking new opportunities for industrial growth, job creation, and community development,” Marokane concluded.
Discover more from Energy News Africa
Subscribe to get the latest posts sent to your email.