Energy Vault Holdings Inc. (NYSE: NRGV) announced a strategic development agreement with Eskom Holdings SOC Limited, South Africa's state-owned electricity utility, to deploy gravity energy storage systems across the region.

The companies plan to build the first gravity energy storage system at Eskom's Hendrina Power Station in Mpumalanga province. The system will provide 25 MW of capacity with four hours of storage, equivalent to 100 MWh, and can scale up to 4 GW according to the companies.

Under the agreement, Energy Vault will supply its EVx 2.0 gravity energy storage technology along with engineering, project management, and training support. The partnership aims to deploy up to 4 GWh of storage capacity across 16 Southern African Development Community member states by 2035.

The EVx 2.0 system incorporates coal ash waste as the storage medium in blocks weighing up to 25-30 tons each. Energy Vault states the technology includes improvements in software orchestration, mechanical operation, energy efficiency, and construction automation compared to previous designs.

"This landmark agreement with Eskom represents a transformational milestone for Energy Vault and for Africa's energy future," said Robert Piconi, Energy Vault's chairman and chief executive officer.

The collaboration supports Eskom's Just Energy Transition Partnership initiative, which focuses on transitioning away from coal while maintaining grid reliability and supporting job creation. Coal currently contributes over 80% of South Africa's electricity supply.

"This partnership with Energy Vault and its innovative gravity storage technology will play a pivotal role in achieving our Just Energy Transition goals," said Dan Marokane, group chief executive of Eskom Holdings.

The announcement comes as the SADC region works to expand electricity access, with 56% of the population now having access to electricity, up from 36% a decade ago.