In August, Enel announced it had reached an agreement for five new wind farms with Nedbank and Absa – representing a total investment of R19.7 billion, with Enel contributing around R3.7 billion in equity in a project that will generate roughly 700 MW of electricity when completed.
Enel currently operates wind and solar plants with a combined output of more than 520 MW.
The five wind farms were awarded in round four of the South African government’s Renewable Energy Independent Power Producer Procurement Programme (REIPPPP).
The facilities are named Nxuba, Oyster Bay, Garob, Karusa, and Soetwater, with a capacity of around 140 MW each.
Vestas will bring in 70 of its V136-4.2MW turbines to the new wind farms, Karusa and Soetwater, which will lie in the Karoo on the border between Northern Cape and Western Cape provinces.
Location of Soetwater and Karusa wind farm projects in the Karoo .
The massive pieces of equipment are expected to be up and running by the second half of 2020. Each blade is 66.7 metres long.
From ground to tip, the turbines will reach a total height of 148.7 metres – taller than the high-rise Michelangelo building (140 metres) in Sandton, Johannesburg.
The turbines have a hub height of 82 metres, putting them into areas with more consistent wind. Hub Height explained. Image IOPScience
According to energy news site Electrek, for every meter increase in turbine height, annual energy output is increased between 0.5% and 1% due to lower turbulence and higher wind speeds.
By comparison, one of the largest onland turbines in the world was made by German company Max Bögl Wind AG. Its hub height sits at 178m tall, and the tower’s total height – from ground to tip – is 246.5m. This is taller than the Carlton Centre in Johannesburg at 223 metres.
Over the last few years wind farms have been pushing the boundaries of height. Bigger rotors and blades make them able to cover a wider are and increases the capacity of the turbine. A study by the International Energy Agency (IEA) Wind Implementing Agreement for Cooperation in the Research, Development, and Deployment of Wind Energy Systems (IEA Wind) forecasts that by 2030 the average hub height will reach 115 metres.
