The Khobab wind farm, 60 km north of Loeriesfontein in the Northern Cape, has completed all 61 of its wind turbine foundations ahead of schedule.

Khobab said in a note released Monday that the first foundation pour was finished on June 30, using low quantities of Portland cement in the concrete formulation. This makes Khobab wind farm the greenest in the country, alongside Khobab’s sister project, Loeriesfontein wind farm.

Slag, a by-product of the iron industry, was used to replace 89% of the cement, creating one of the world’s lowest carbon footprints for any wind farm foundation. “This revolutionary formula was tested and successfully implemented by our sister wind farm, so we were confident from the onset to use the same formulation,” said Khobab project manager Kevin Foster.

Each turbine base has a diameter of 19 m, comprising over 45 t of reinforced steel.

Situated in the Hantam municipality, the wind farm employs most of its labour from the Loeriesfontein community. “We would like to thank the 100-plus local workers who have ensured that our project has continued to forge ahead on time; their commitment is appreciated,” added Foster.

He further noted that, as part of Khobab’s commitment to skills development and community development, the project has provided local employees with transferable skills training that can be used at other wind farms or other construction sites.

The material excavated from the foundation bases was of a good quality and was subsequently reused on site, specifically for the wind farm road construction and in preparation for the turbine hard stands, situated adjacent to the foundations.

When operating at full capacity, the Khobab wind farm will generate 563 500 MWh of clean renewable energy a year and is expected to supply electricity to power up to 120 000 South African homes.

Most of the 99 m turbine towers will be manufactured by Western Cape-based GRI, which is based in Atlantis. Civil and electrical works will be completed by a consortium comprising Murray & Roberts Construction and Consolidated Power Projects.

The Khobab wind farm is part of Round 3 of the South African government’s Renewable Energy Independent Power Producer Procurement Programme and is expected to be operational by December 2017.