Therefore, with its unparalleled potential for renewable energy, the development and implementation of energy storage technologies is vital to ensure and improve grid stability and security, across Africa.
Drakensberg Pumped Energy Storage Scheme – 27.6 GWh
Designed to generate electricity for 10 hours per day through its four 250 MW turbine generators, the Drakensberg Pumped Storage Scheme is an energy storage facility, situated in the northern parts of the Drakensberg Mountain range of South Africa, which provides up to 27.6 GWh of electricity storage. Water from the 27 million cubic meter reservoir is pumped into the Driekloof Dam — a small section of the Sterkfontein Dam in South Africa’s Free State province — during times of low national power consumption, from where it is released into the Drakensberg’s Kilburn Dam, an escarpment with a capacity of 36 million cubic meters, through its turbine generators, giving the Dam a total capacity of 1,000 MW, during times of high electricity demand.
Ingula Pumped Energy Storage Scheme – 21 GWh
Comprising four 333 MW pump turbines that generate a total of 1,332 MW of electricity, the Ingula Pumped Storage Scheme (Ingula PSS) is a pumped storage power station that encompasses two dams, designed for water capacity of 22 million cubic meters. Straddling the border of South Africa’s KwaZulu-Natal and Free State provinces, the Ingula PSS has an energy storage capacity of 21 GWh, or 15.8 electricity generating hours.
Noor Ouarzazate Solar Power Complex – 3 GWh
Situated in the Drâa-Tafilalet Region of the Kingdom of Morocco, approximately 10 km from the city of Ouarzazate, the 580MW Ouarzazate Solar Power Complex is the largest concentrated solar power (CSP) plant in the world. Capable of storing solar energy in the form of heated molten salt, the power station was developed in three phases, encompassing the 160 MW Noor I CSP plant; the 200 MW Noor II CSP plant; the 150 MW Noor III CSP plant; and the 70 MW photovoltaic Noor IV CSP plant. The Noor I CSP plant features a full-load molten salt storage capacity of three hours, while the Noor II and III CSP plants are able to store energy for up to seven hours each, thus providing a combined total of 3 GWh of electricity storage. Output from the Ouarzazate Solar Power Station is conveyed to a 225/60 kW station, located nearby the complex.
Bokpoort CSP Project – 1.3 GWh
The Bokpoort CSP Project is considered among the most efficient solar plants in the world. Situated in the South African town of Bokpoort in the Northern Cape province, the 50 MW CSP plant, with an output capacity of 200 GWh per year, uses a 1.3 GWh molten salt energy storage facility, capable of providing approximately 9.3 hours of thermal energy storage, to serve up to 21,000 households while offsetting 230,000 tons of CO2 per year. The facility comprises a solar field, a power block that consists of a solar steam generator and a steam turbine, and a thermal-energy storage system that consists of two tanks of molten salts.
KaXu Solar One – 1,650 MWh
With a planned annual net output of 320 GWh, the 100 MW KaXu Solar One CSP plant, located approximately 40 km north-east of the town of Pofadder in the Northern Cape province of South Africa, is capable of providing up to 2.5 hours of thermal storage capacity through its molten salt-based thermal energy storage system with a storage capacity of 1,650 MWh. With electricity conveyed from the plant to Eskom’s Paulputs Transmission Substation, located 5km from the plant site, via a 132 kV overhead transmission line, the solar project is capable of serving up to 80,000 households in the province while offsetting approximately 315,000 tons of CO2 per year.