Khobab wind farm has announced the completion of its final wind turbine foundation. All 61 of its wind turbine foundations have been completed ahead of the schedule, on 5 December 2016.
The first foundation pour was finished on 30 June 2016 with employees from the local community working tirelessly through the days and putting in long hours. The foundations used extremely low quantities of Portland cement in the concrete formulation of its wind turbine foundations. In fact, these turbine foundations are the greenest in the country, alongside Khobab wind farm’s sister project, Loeriesfontein wind farm.
Each turbine base has a diameter of 19 metres comprising over 45 tonnes of reinforced steel. These turbine foundations are utilising one of the world’s lowest quantities of Portland cement in the concrete formulation. Slag, a by-product from the iron industry, is used to replace 89% of the cement. This has resulted in what is believed to be, 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 Kevin Foster, Project Manager for Khobab wind farm.
Situated in the Hantam Municipality, 60km north of Loeriesfontein in the Northern Cape, Khobab wind farm employs the majority of its labour from the Loeriesfontein community, in support of local employment and upliftment. “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 continued saying, “As part of our commitment to skills development and community development, we have provided local employees with transferable skills training, which 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 re-used on site, specifically for the wind farm road construction and in the preparation of the turbine hard stands, situated adjacent to the foundations.
“In closing, we would like to once again thank everyone on the construction team, who worked diligently to complete these foundations, from batching the concrete to floating it,” concluded Foster.
The site was chosen because of its excellent wind resource, its proximity to national roads for wind turbine transportation, the favourable construction conditions, municipality and local stakeholder support, the straightforward electrical connection into Eskom’s Helios substation approximately 11km south of the site, and studies showed that there would be minimum environmental impact.
When operating at full capacity, the Khobab wind farm will generate approximately 563,500 MWh of clean renewable energy per year; this is expected to supply electricity to power up to 120 000 South African homes.
The majority of the 99m turbine towers are to be manufactured by GRI, in Atlantis, in the Western Cape. Civil and electrical works are to be completed by a consortium comprised of Murray and Roberts Construction and Consolidated Power Projects.
The Khobab wind farm is part of the South African Government’s Round 3 Renewable Energy Independent Power Producer Procurement Programme (REIPPP) is expected to be operational by December 2017.