Do wind turbines ever all stop at once?

Asked by: Jamie Hill, Inverness

As critics of wind power point out, there is a risk involved in relying on the weather as a source of electricity. In February 2003 parts of Denmark - the world's most wind power-dependent country - suffered a virtual dead calm for a week, during which turbines in the west of the country produced no power at all.

A similar event struck Germany in November 2003, when a six-hour lull led to the nation losing the equivalent of three conventional power stations.

And in February this year, parts of Texas came close to a blackout following the sudden loss of over 80 per cent of the state's wind power production, caused by a change in the weather.

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