ACWA South Africa solar power
(Image: ACWA/SolarReserve)
  • Saudi-based ACWA Power has finally announced financial close on the Redstone Concentrated Solar Power plant, after being awarded the contract in 2015.
  • The project, which has secured R11.6 billion in funding, is the largest renewable energy investment in SA to date.
  • Located near Postmasburg in the Northern Cape, Redstone is due to produce 100 MW, and use molten salt technology to store energy. 
  • Power from the plant is expected to be delivered at the end of 2023.
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ACWA Power has finally confirmed financial close at R11.6 billion to construct the Redstone Concentrated Solar Power (CSP) plant in the Northern Cape. This comes six years after its bid was approved by South Africa's Department of Energy.

Based in the Saudi Arabian capital of Riyadh, the International Company for Water and Power Projects – better known as ACWA – was named a successful bidder in South Africa's Renewable Energy Independent Power Producer Procurement Programme (REIPPPP) in 2015.

The construction of the Redstone CSP, which has attracted the largest renewable energy investment in South Africa to date, was due to begin in 2016 but was delayed due to complications with Eskom. In 2018, the purchase power agreement (PPA), which was reportedly worth around R50 billion for a 20-year contract, was signed by Eskom.

Shortly after announcing that financial close was "nearly complete" in 2019, ACWA's partner in the Redstone project, SolarReserve, declared bankruptcy amid a failed solar project in the United States.

On Monday, ACWA confirmed that it had secured financing from several local and international funders, including the African Development Bank (AfDB), ABSA, Investec, Nedbank, and Sanlam. The Redstone CSP project is due to come online in the fourth quarter of 2023.

ACWA South Africa solar power
(Image: ACWA/SolarReserve)

The Redstone plant will use a 250-metre tall 12-hour thermal storage tower with molten salt technology pioneered by SolarReserve. This allows stored heat to power turbines during bad weather or at night, so providing a consistent supply of electricity.

This storage technology is currently being used by the Bokpoort CSP project located near Groblershoop in the Northern Cape and built by ACWA in 2015. The 50 MW CSP set a new winter production record in August 2020, of 21.7 GWh, thanks to plant's thermal storage capabilities.

ACWA South Africa solar power
(Image: ACWA)

Redstone, located near Postmasburg, approximately 170 km east of Upington, will cover 648 hectares and produce 100 MW of energy, double the supply of the Bokpoort CSP. The project is expected to power some 200,000 households and create more than 2,000 jobs during the peak of its construction phase.

"Redstone CSP will displace an estimated 440 metric tons of [carbon dioxide] emissions per year," says ACWA.

"The project is certified under the Climate Bonds Standard and Certification Scheme and aligned with the goals of the Paris Climate Agreement which seeks to limit global warming to under 2 degrees Celsius."

The Redstone plant will be built adjacent to the 75 MW Lesedi and 96 MW Jasper photovoltaic (PV) solar power projects, which were both developed by the now-defunct SolarReserve.

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