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Picture 10 John Webley is a retired Morgan Stanley Managing Director and is currently leading a campaign against wind turbines in rural Kent.

National Grid has just published its consultation document “Operating the Electricity Networks in 2020” and large sections of the report deal with the problems of managing increasing electricity generation from onshore and offshore turbines.

The wind industry, and the British Wind Energy Association (BWEA) in particular, have successfully managed to distract attention from a quite extraordinary admission in the document which deserves urgent attention by the Conservatives.

Although many of us have been pointing out for some time that the periods of total wind collapse across the whole UK are far more frequent than previously admitted, this has never been publicly acknowledged. Worse than that, the BWEA has been responsible for totally misleading information. In their June 2008 submission to the House of Lords’ Select Committee on Economic Affairs, during the committee’s review of “The Economics of Renewable Energy”, the BWEA stated that:

 “Additional costs are attributable to the relatively low “capacity credit” that wind power has: this factor reflects how much wind power can be expected to contribute when demand for electricity is at a peak, and this is 20-30% of the nameplate capacity of the wind generators.”

Given that a generous estimate of average annual output from wind turbines is only 30% of nameplate capacity this statement is clearly patent nonsense since it implies that average output is nearly always maintained. It was nevertheless offered up as a contribution to an important debate.

The Government’s own estimate of the statistically reliable output from wind turbines at times of peak demand, as set out in the 2008 Renewable Energy Strategy Consultation, is 10-20% and it is clearly this level which has been used in determining policy. Although lower than the BWEA’s estimate, it is, nevertheless, still absurd.

The reality, as confirmed in National Grid’s document, is very different. In paragraph 5.13 it says “…we have seen that load factors of less than 1% are plausible at all times of the year.”  This effectively means that absolutely no reliance can be placed on wind turbine output at times of peak demand and National Grid’s document has another chart which provides the evidence that these very low wind speeds occur at times of winter peak demand consistently over the years.

What does this mean, apart from the obvious answer that wind turbines require to be totally backed-up (a fact still contested by some)?

National Grid goes further and, taking all identified energy saving measures into account, plots out generating capacity through to 2025 and shows what the implications of a low wind situation are when trying to meet demand.

By 2020 the result is quite shocking. In 2020 it has been assumed that there would be 10GW of onshore wind and 19.4GW of offshore wind. The average output from the turbines is assumed at 30% of nameplate capacity and after reducing for National Grid’s estimate of lack of availability for downtime, the total average annual output of these thousands of installed turbines would be 7.8GW

However, in a low wind situation, when the electricity from wind drops away, it is estimated that the shortfall in total generation available could be in excess of 7GW. In other words, this is a shortfall which will be there in any event and current plans assume that it will be met by wind turbines. When the turbines stop going round, which they will, the shortfall reappears.

The shortfall is actually even larger than shown by the chart since National Grid has also optimistically assumed that, by 2020, there would be 2.9GW of capacity of embedded wind i.e. domestic and small scale wind turbines. It is, in part, the increasing contribution from these that enables National Grid to assume that peak electricity demand will remain flat between now and 2020 at 60GW. However, when the wind stops blowing these turbines will stop as well, placing further pressure on demand and increasing the shortfall. National Grid has confirmed to me that this has not been taken into account.  

National Grid concludes that the only way that this shortfall can be met is through identification of further sources of reserve as well as measures to reduce peak demand. It goes further to say that unless action is taken on this front “involuntary demand control measures would be required.”  A euphemistic way of saying that the lights will be turned out.

It is also worth noting that there is now data available which shows that the frequency of the total wind collapse across the whole UK is not only much more frequent than generally understood but that these low wind situations are very often across the whole of Europe at the same time. For example, between October 2008 and February 2009 there were 58 days when turbine output across the whole UK would have dropped below 5% and on 24 of these days output would have remained below 5% all day. During the same five month period, on the E.ON network in Germany, where readings are taken ever quarter of an hour, 19% of all readings were showing total output at less than 5% and an astonishing 9% at less than 2%.  

In summary, the Government is pushing ahead with a renewable energy policy which, by 2020 would have average annual output from wind turbines of nearly 8GW but this output would often be unavailable at times of peak winter demand and present projections by National Grid show that nearly the same amount of additional back-up or energy saving measures are required in order to avoid a serious energy shortfall. National Grid makes the astonishing revelation that the means of addressing this inevitable and dramatic shortfall have not been identified.

The confusion in the renewable energy debate has been considerable and the facts are not well understood by the public and many politicians. However, this consultation document finally lays bare the reality of what is being proposed and should cause considerable alarm. If this document does not confirm, once and for all, the gravity of the situation and that a non-nuclear strategy is foolhardy in the extreme, nothing else will.

34 comments for: John Webley: The lights would indeed go out under Labour

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