10: Concentrated solar launched in SA

KaXu Solar One, near Pofadder in the Northern Cape, is South Africa’s first concentrated solar power (CSP) plant in commercial operation. The 100 MW solar plant incorporates a storage system using molten salt that enables electricity production for 2.5 hours after sunset or before dawn.

This technology uses parabolic-shaped mirrors set to track the movement of the sun and concentrate solar radiation onto a receiving tube. A heat absorbing fluid inside the tube transfers the thermal energy to a heat exchanger. The energy is used to turn water into steam, which drives a turbine to generate electricity.

Use of thermal energy storage technology with molten salt-filled storage tanks gives the plant the ability to generate electricity after sunset or in cloudy periods, allowing it to adapt energy production to the peaks of demand.

KaXu Solar One is 51% owned by Abengoa Solar. It was financed by the Industrial Development Corporation, which holds a 21% stake in the project. The remaining ownership is held by the KaXu Community Trust.

The solar plant is capable of providing renewable power to about 80 000 South African homes, and has a 20-year power purchase agreement in place with Eskom.