The contract with a consortium led by Mainstream Renewable Power will see Siemens install 157 of its SWT-2.3-108 turbines across the Khobab, Loeriesfontein 2 and Noupoort wind farms.
The deal includes a 10-year service and maintenance agreement.
The 140MW Khobab and the 140MW Loeriesfontein 2 wind farms are situated in the Namakwa District Municipality and the 80MW Noupoort facility is located in Umsobomvu Local Municipality, 400km north of Port Elizabeth.
Germany-based Siemens plans to start turbine installation in August 2015 and the three projects are expected to be commissioned from early 2016 to the end of 2017.
Siemens CEO of wind power and renewables division Markus Tacke said: "This order also clearly demonstrates that, with its Renewable Energy Independent Power Producer Procurement Programme (REIPPP), South Africa is on a successful path for achieving the governments stated goal of installing 3,725 megawatts of renewable energy capacity."
Siemens had earlier delivered its 2.3MW turbines to Mainstream’s 138MW Jeffrey’s Bay wind farm, which was commissioned in 2014.
Mainstream has recently launched a $1.9bn pan-African renewable energy platform with Actis.
The platform, dubbed Lakela Power, will develop between 700MW and 900MW of wind and solar power projects across the continent by 2018.
The Khobab, Loeriesfontein 2 and Noupoort wind farms will form the core of the platform.
Image: Siemens will deliver 157 SWT-2.3-108 turbines for three wind power projects in South Africa. Photo: Courtesy of Siemens AG.