Wind-energy developer pressing ahead with five SA projects

Wind energy developer G7 Renewable Energies has confirmed that it is pressing ahead with the development of five possible wind farms in the Western Cape and Northern Cape provinces, where the company hopes to launch project within the next two years.
Advertisements requesting public comment have been published for the five sites, including: one near Lamberts Bay; a second near Klawer; a third in the Richtersveld, south of Alexander Bay; a fourth near Witberg; and a fifth in the Roggeveld, between Matjiesfontein and Sutherland.
G7 added that these projects would precede several larger projects that it hoped to build, some producing up to 750 MW of power.
The sites were identified using a wind atlas produced by G7 director Dr Kilian Hagemannfor his PhD in atmospheric science. Hagemann’s thesis concluded there was sufficient wind in South Africa to provide 35% of South Africa’s electricity. His calculations, done in 2008, were based on electricity demand in 2007.
“The wind resource is vast in South Africa. The supply is not the limiting factor – there is a percentage that you can rely on no matter the weather conditions,” said Hagemann.
A previous wind atlas, drawn up in 1995, found that only areas within 50 km of the coast, as well as part of the Drakensberg escarpment, had enough wind to warrant wind farms. 
However, Hagemann’s map found that almost half the country had enough wind to be considered a “good” supply and that sizeable inland regions were an excellent resource.
There are seasonal variations in wind supply, but these are said to be aligned with power demand patterns, with supply rising in South Africa’s winter Months.
He added that: “there are some plans being bandied about in the industry, which we think are unrealistic, although we might achieve things on this scale in five to 10 years time. Wind power is new in South Africa, and we must learn to walk before we can run.”
The South Africa Wind Energy Association (Sawea) has estimated that 25% of South Africa’s total electricity requirements could be supplied by wind resources by 2025.
In addition to it being a proven technology that can be relatively quickly deployed, G7 director Nicolas Rolland asserts that wind energy is also cost competitive with coal-fired production.
“Eskom’s latest coal-fired power station, Kusile, will produce power costing about R30-million/MW of installed capacity. Wind developers in South Africa are working at a far lower cost – R20-million to R25-million per MW of installed capacity. Taking reasonable assumptions for the discount rate, fuel, operation and maintenance costs, results in levelised cost of anywhere between R1 to R1,25 – cheaper than the electricity from Kusile,” Rolland calculates.
Yet G7 is not convinced that government’s eagerly awaited second Integrated Resource Plan, or IRP2010, will fully reflect the benefits of wind in it allocation to the overall generation mix in the coming two decades.
“But this is a real passion of ours, and we’re going to get stuck into it,” Rolland avers.
“If the IRP allocation to wind is really tiny, we’ll keep pressing ahead. There’s nothing stronger than an idea whose time has come,” added Hagemann.
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