Wind power savings

Wind turbines generate for 70-85% of the time but most of this time the output is rather low

I feel that the article in the August Journal by the Chairman of the Institution’s Renewable Committee cannot go unchallenged. He states ‘There is a clear and significant net carbon dioxide reduction over a wind turbine's lifetime‘ and quotes amongst other findings those of The Parliamentary Office of Science and Technology. However as he himself recognises none of the sources quoted take account the need for back up for when the wind does not blow and the effect of running this back up plant at reduced outputs and lower efficiencies.
 
While it is no doubt correct that wind turbines generate for 70-85% of the time, the fact is that for most of this time the output is rather low (less than 30% of rated capacity for some two third's of the time according to the analysis published by Consulting Engineer Stuart Young) and usually very little at times of system annual peak loads.

Furthermore none of these studies take into account the reduced output that wind turbines seem to experience with time – not much more than half the original annual load factors after ten years according to the analysis carried out into UK and Danish experience by Professor Gordon Hughes of Edinburgh University.
 
To take account of all the various factors it would be essential to carry out total system studies of the type carried out of actual operations on  the Irish system and Utilities in Western USA.These have shown that for systems with large amounts of installed wind power the savings in CO₂ emissions are negligible even on an operating basis and before taking into account the CO₂ involved in construction and and installation.

Unfortunately the basic data to allow such meaningful studies to be carried out for the UK system is simply not being made available .
 
Sir Donald Miller, Renfrewshire

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