The 89 MW Castle wind farm, developed by a consortium led by African Clean Energy Developments (ACED), has achieved commercial operation and is now supplying electricity to Sibanye-Stillwater’s South African operations via a wheeling agreement with Eskom.
Located near De Aar in the Northern Cape, the wind farm connects to Eskom’s Hydra main transmission substation, 25 km from the site. The facility comprises 16 Goldwind turbines rated at 6 MW each with a hub height of 110 m and tip height of 192,5 m.
Castle is supplying power under a 15-year power purchase agreement. The wind farm is expected to produce 309 GWh of electricity annually, meeting approximately 5,5% of Sibanye-Stillwater’s South African energy demand. This is expected to reduce the company’s Scope 1 and 2 emissions by 321 000 tonnes of CO₂ equivalent per year – approximately 5% of its total – and mitigate exposure to potential carbon tax liabilities.
“This marks a milestone for ACED, Sibanye-Stillwater and South Africa’s private renewable energy sector with Castle being the largest private-offtake wind farm in operation in South Africa to date,” the project partners said in a joint statement.
Shareholders in the Castle wind farm development include ACED and the IDEAS Fund, managed by African Infrastructure Investment Managers (AIIM), as well as Reatile Renewables. AIIM is a division of Old Mutual Alternative Investments. Energy Infrastructure Management Services Africa, an ACED and AIIM affiliate, will manage Castle’s operations. RMB acted as sole mandated lead arranger.
Construction took 22 months with Adenco Construction responsible for the electrical balance of plant and CSV Construction on civil works.
“Projects such as these require huge amounts of collaboration and cooperation between a vast array of stakeholders. We are very grateful for the role played by all. Benefits extend way beyond ‘buyer and seller’ with renewables projects driving sustainable economic growth on a macro and micro level for South Africa. We are very proud of this,” said James Cumming, CEO of ACED.
Castle is one of two renewable energy projects being developed by the consortium for Sibanye-Stillwater. The second, the 140 MW Umsinde Emoyeni wind farm project announced in May 2024, is expected to reach commercial operation in late 2026.
