Ingula Pumped Storage Scheme

ABB, the leading power and automation technology group, has won an order worth US$23 million from Eskom, South Africa’s leading electric utility, to supply an electrical balance of plant (eBoP) solution for the Ingula Pumped Storage Scheme (PSS), currently under construction on the border of the Free State and KwaZulu-Natal provinces in South Africa.
The Ingula plant will have the capacity to generate 1,333 megawatts (MW) of hydropower to be integrated into the South African grid, when fully operational in 2014. It is estimated that South Africa will require an additional 40,000 MW of power by 2025.
As part of the turnkey eBoP solution for the power plant, ABB will be responsible for the design, engineering, supply, installation and commissioning of the project. Key products to be supplied include the service and auxiliary transformers, dry-type distribution transformers and medium- and low-voltage switchgear.
The Ingula PSS will comprise an upper and a lower reservoir. The upper reservoir will have a total capacity of 22.6 million cubic meters (MCM) and an active storage of 19.3 MCM. The lower reservoir will have a 26.3 MCM capacity and active storage of 21.9 MCM. The reservoirs, 4.5 kilometers apart, will be connected by underground waterways to a subterranean generating plant with four 333 MW pump turbines.
During times of peak energy consumption, water will be released from the upper reservoir through the pump turbines to the lower reservoir to generate electricity. When energy consumption is low, the process will be reversed, and water will be pumped from the lower to the upper reservoir.