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Wind turbines in the Western Cape

Last week I wrote about how the Western Cape is about to have its name changed to Windfarmland, since there are proposals to put up 2 000 wind turbines, all 80 m to 100 m high, spread over the countryside from Paternoster to Betty’s Bay.

If those turbines were in place right now – as I write this article – I can tell you they would not be turning. The wind speed in the Western Cape has been very low or nothing over the last six days. This is because of a phenomenon in the Western Cape known as winter. The wind does not blow much in winter, since the weather turns to vast, unending sheets of rain, which leaves turbines in dripping stillness. This means that, for part of the year, at least four months, the turbines will not turn. During this time, the conventional power system will have to supply the load. Thus, adding wind turbines to the generation mix is not very cost effective, since it makes other assets underused. Further, the wind power density in the Western Cape is about 250 W/m2, which is not a lot.

The main objections to wind turbines, which have been voiced in other countries, are the visual disfigurements of the landscape and the noise from the turbines. In terms of visual disfigurement, we know that a 30-storey building is about 100 m high and that a wind turbine structure is 80 m to 100 m tall. According to South Africa’s Civil Aviation Act, wind turbines cannot be disguised. In fact, they have to be made extra visible so that aircraft can avoid them. Further, they destroy the visual aspect of the skyline and the sense of place of the countryside – the beautiful West Cape coast cannot be made beautiful by the addition of some out-of-place vast structures.

Ironically, the cellphone tower suppliers disguise their towers as trees – tall trees, but trees, so as to soften the visual aspect. Once you see a countryside visually destroyed by wind turbine structures, you never forget it.

Regarding noise, the British Wind Energy Association says: “Well-designed wind turbines are generally quiet in operation and, compared with the noise of road traffic, trains, aircraft and construction activities . . . the sound of a wind turbine generating electricity is likely to be the same level as noise from a flowing stream 50 m to 100 m away or the noise of leaves rustling in a gentle breeze.”

Dear, dear – leaves in a gentle breeze?

There are many court cases going on right now which have as their main theme a complaint about wind turbine noise. In New Zealand, there have been 870 complaints about a single wind farm. All the complaints are about a ‘pulsing sound’ which disturbs people up to 2 km from wind farms. Dr Nina Pierpont, of the US, writes: “Industrial wind turbines produce significant amounts of audible and low-frequency noise.”

The main issue, the guilty culprit, is the A-weighted decibel scale, or dBA. This scale is used for measuring the effect of noise on humans – it is supposed to mimic the hearing of the ear. But the scale more or less predicts that humans cannot hear frequencies of about 30 Hz or below. This is wrong – they can, and do, and these are the ‘black noise’ frequencies which are produced by wind turbines and disturb people.

The short answer is that wind farms are going to make money for a small group of people under the guise of saving the planet when, in fact, they will affect the sense of place and visual peace of a vastly greater number of people. Say no to wind turbines. Say no, no, no.

We are very sun rich: even if we cannot use the full 1 000 W/m2 which is available from sunlight, it is still a far cry from wind, which can only give us about 250 W/m2 on average. Bring on solar power, I say. It does not blot the horizon, and it is quiet, real quiet.