Tuesday, 11 September 2012

The answer is still blowing in the wind

This report a couple of weeks ago demonstrated:

a) that using wind energy leads to significant carbon savings, and
b) that use of wind energy at a level of up to around 20% of the UK’s electricity needs poses no threat to security and reliability of supply.
Neither of these conclusions will come as any surprise to those of us who support the inclusion of wind as part of the overall energy mix.  And I suspect that neither will be believed by those who oppose wind energy and prefer unsubstantiated assertions to the contrary. 
Indeed one reaction which I saw to the report in the letters column of the Western mail simply dismissed the report on the basis that it was written by individuals who had a vested interest.  Now clearly, having a vested interest in the outcome of a particular proposition means that one should read very carefully what people have to say on the subject, but it is not enough in itself to dismiss a report with which one disagrees.
Part of the problem in reconciling opposing views is the difficulty in putting precise figures on some aspects of the calculation.  The report itself can only estimate the CO2 savings, and provides a clear explanation of why that is so.  (And in fact, that makes it no different from many other areas of policy; it is invariably the case that while some things can be precisely measured, others always have to be estimated.)  I don’t doubt that the lack of precision will be seen as a cloak from behind which the naysayers will continue to use words such as “useless”.
On a related note, one anti-wind letter writer to the Carmarthen Journal last week came up with a “solution” to our electricity needs which avoids the use of wind energy completely.  He said that we should use electricity to produce steam to generate electricity, and that
"… a water screw producing enough electricity for just a few thousand homes can instead be used to produce enough steam to turn turbines which produce electricity for tens if not hundreds of thousands of homes ...”
In essence, his argument seems to be that small amounts of electricity can be used to generate steam, but that steam can then generate 10 or even 100 times as much electricity as was used to generate the steam in the first place.
If that were true, it would be a simple and elegant solution to the world’s energy needs.  Indeed, by simply repeating the process several times over, a small mountain stream in mid Wales could meet the entire world demand for energy.  Which sort of exposes the basic fallacy in the argument.  Unfortunately, power to amend the first law of thermodynamics has not yet been devolved to Westminster, let alone to Cardiff.

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