Name of the Project
Renewable underground pumped hydroelectric energy storage (Ruphes) project.

Location
Gauteng, South Africa.

Project Owner/s
Sibanye-Stillwater.

Project Description
thyssenkrupp Uhde Africa and Wismut have been appointed to execute a prefeasibility study (PFS) for the proposed Ruphes project at Sibanye’s Driefontein mine.

Sibanye believes a Ruphes system may support its commitment to carbon neutrality by 2040.

The PFS aims to test and develop the technical and commercial concept to enable Sibanye to assess the viability and benefits of the project as an option for mine closure, and facilitate the post-mining economic development of communities through the provision of sustainable energy and water. 

The project involves repurposing unused shafts and associated mine tunnels for Ruphes. Underground pumped-energy storage uses development mining tunnels, previously used to access the gold reefs, as upper and lower reservoirs that will allow for energy storage and generation.

When surplus electricity from renewable or other sources is available, water is pumped to the upper reservoir.

As soon as the electricity is required, the water discharges from the upper reservoir to the lower reservoir under gravitational force, generating electricity through a generator coupled to a turbine in the shaft system.

Potential Job Creation
Not stated.

Capital Expenditure
Not stated.

Planned Start/End Date
Not stated.

Latest Developments
None stated.

Key Contracts, Suppliers and Consultants
thyssenkrupp Uhde Africa and Wismut GmbH (PFS).

Contact Details for Project Information
Sibanye-Stillwater, tel +27 11 278 9600.