An article in New Scientist magazine discusses the results of a recent report
on large wind turbine performance by the Renewable Energy Foundation.
The country's first generation of wind farms is delivering less power
than predicted by government.
Scottish and offshore wind farms generate around 30% of their theoretical
capacity. England, however, doesn't have enough wind, and the figures there
range from 26% to 8%.
One of the problems is that the power varies as the cube of the
windspeed, which magnifies the difference in output between clam and
Much of the time,
it's either windy or calm across the whole country. The network of wind
farms might have been expected to compensate for a low windspeed in
one area by generating more electricity in an area where it's windier.
1.When power is available it is not necessarily at a time when it can
be employed - for example, in the middle of the night, when total
demand is being met by nuclear power stations.
2. The network of wind farms is not "evening out" the variations in
output in different locations. A low windspeed in one area is rarely balanced by a high
windspeed in another.
This results in a much larger "spinning reserve"
requirement when fossil fired plant is running it its most inefficient
3. "30% of their theoretical capacity". Does this mean delivered
to the Grid, or "possibly available if the Grid wanted it"?
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