Figures show wind power is useless for grid electricity

ETERVenn of Windlab SA makes strange and wrong arguments for wind power in “The answer to our country’s energy requirements is blowing in the wind”, Insight, September 20.

Wind power, although excellent for small applications such as wind pumps on Karoo farms, is useless for grid electricity. Billions of dollars have been poured into it in Europe and the US, and it has proved an expensive failure, bad for the environment, bad for the economy, bad for electricity supply and good only for the rich developers.

Because wind power is so expensive

Pand unreliable, it depends completely on huge operating subsidies enforced by the government. Consumers and taxpayers are compelled to pay very high prices for wind power, whether they want it or not, whenever the wind happens to be blowing at the right strength, which is seldom and unpredictable. No financier will put one cent in wind power without these enormous subsidies.

The unreliability of the wind, which Venn dismisses as immaterial, is profoundly important. In Europe in the bitterly cold winter of December 2010, with record electricity demand, tens of thousands of wind turbines from England to Germany were producing next to nothing. The same was true of subsequent winters. These failures could not in any way be “accommodated by grid system operators”.

The wild, unpredictable variations in wind power put tremendous strain on the electricity network. German industries are already coming under strain because of it. Electricity demand, from highest to lowest, typically varies by about two to one. Wind production, from highest to lowest, varies by hundreds to one.

On the slaughter of birds by wind turbines and cats, the California Energy Commission found that a single wind farm, Altamont Pass, killed 4 700 birds a year, including 1 300 protected raptors, including 100 golden eagles. Could Venn tell us how many eagles are killed by cats?

Wind power has appallingly low capacity factors (which show how much the power plant produces compared with its capacity). The capacity factor for wind in Germany, Europe’s largest user, is 17 percent. The Darling Wind Farm: 18.9 percent. A typical Eskom coal plant: 70 percent. Koeberg: 80 percent.

Wind power takes a long time to build. The Darling Wind Farm, which produces 8.6 gigawatt-hour a year, took eight months. The Medupi coal station, which will produce 29 000GWh a year, will take 10 years.

If you wanted to build enough wind turbines to produce the same amount of electricity as Medupi and built them at the same rate as Darling, it would take over 2 000 years.

If you built Darling wind turbines within the time of Medupi’s building, you would need to build 1 358 a year, or more than three every day for 10 years. ANDREW KENNY NOORDHOEK