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BBC1, South East - Wednesday, 7.30pm 25/02/2009

“INSIDE OUT - Are wind farms the answer to our energy problems?”

Overview by Prof Ian Fells of the looming electricity shortfall if wind is relied upon.

Den Brook Wind Turbines – Where does the balance of advantage lie?

The question of whether or not to construct wind turbines in a particular location can only be answered by considering where the balance of advantage and disadvantage lies.

The advantages are, in principle, clear. They relate to the benefit of delivering electricity from a renewable source and a possibility for savings in greenhouse gases in the atmosphere. These are ‘hard’ items susceptible to precise measurement. There may also be some temporary benefits arising from construction work, but for our purposes these are ignored as peripheral.

The disadvantages cannot be measured on an unambiguous scale. Many depend on perceptions of the value of such items as landscape, amenity, the implications of noise and visual effects of turbines on the local populace, and the effects on wildlife etc. But difficulty of measurement does not mean lack of importance. Indeed these effects, in aggregate, contribute greatly to our quality of life.

The Den Brook Valley is located some 5 miles from Dartmoor National Park. The landscape is traditional Devon farming land of small fields and hedgerows. There are no large man made buildings or structures, the whole area being set against the backcloth of the northern face of Dartmoor - the highest part of the moor. The construction of nine turbines, all but 400ft high, will alter the landscape totally. Instead of a pleasant rural landscape set against Dartmoor, it will be transformed into an industrial scene with views of Dartmoor only visible through moving turbine blades. The developer claims that “beyond approximately 7 kms the turbines would be smaller scale landscape elements allowing other elements to be more prominent and they would only have a slight effect upon landscape character.” This is simply not the case. Dartmoor is the most prominent landscape feature for the whole of this area yet it will only be visible through the turbine blades at distances far greater than 7 km, such is the height of the proposed turbines.

The amenity of people will also be affected adversely. Large numbers of people in the surrounding villages will be unable to step outside their properties without being confronted by these huge turbines. They will be the dominant feature from which there will be no escape. The developer claims that “there would be no significant visual effects upon any of the nearby settlements including North Tawton and Bow.” This is patently not the case.

Nor will the loss of amenity be confined to local people. Given the topography of Devon between Dartmoor and Exmoor the turbines will be highly visible even from parts of North Devon. It is not overstating things to say that the amenity of large numbers of both Devon residents and visitors will be damaged as a consequence of constructing these turbines. We must expect that this will have knock-on effects on earnings and employment.

The noise implications of constructing the turbines will be serious but transitory. The ongoing noise implications of operating the turbines are far more serious. The developers would have us believe that there will be little noticeable effect, but until relatively recently they were not prepared to share the data and analysis that led them to this conclusion. Following Court action, some relevant data has now been produced - this demonstrates that there were errors in the developer’s background noise measurements and analysis. In consequence, a Court of Appeal Judge has now set aside the decision of the Planning Inspector dated 22.3.07 approving the construction of the turbines.

Over and above the errors, it is our contention that the methods used for measuring the potential noise nuisance from the turbines are quite inadequate, particularly in respect of "amplitude modulation" – in simple terms the deep ‘whoomph, whoomph, whoomph’ of moving turbine blades. (More detailed analysis of the noise issue can be found elsewhere on this site.)

Proponents of wind turbines argue that the effects on wildlife are minimal. This claim is increasingly coming into question. Evidence from several sources indicates that the effects on bats and bird life, particularly raptors, can be serious. Significant numbers of bats, owls, sparrow hawks and buzzards are found in Den Brook Valley.

Have the alleged advantages of the development been proved? The developers claim that the proposed turbines will serve the electricity requirements of between 10,064 and 13,140 houses. One cannot help but be amused at the juxtaposition of alleged accuracy ‘10,064 houses’ together with alleged uncertainty ‘between 10,000 and 13,000 households’. If one can forecast to the level of an individual house, how come there needs to be a band of 3000 houses to encompass the number of houses served? Like many of the developer’s claims there is no explanation, just assertion.

Further assertions are made about the amounts of greenhouse gases these amounts of electricity generation will save. There are serious grounds for suggesting that all these claims are gross overestimates. Indeed the BWEA have recently accepted that their calculations of CO2 savings which were also used by RES, have overestimated reality by a factor of 2.

Calculations, which were not challenged at the Public Inquiry, suggest that the developers estimates are not only highly optimistic, both in terms of electricity generation and greenhouse gas savings, but also average out what will be significant variations in output levels by hour, day and month. It is these latter considerations that cause E-On, in discussing its experience of wind turbines in Germany, to conclude that a constant 90% back-up facility from conventional power stations is essential to ensure grid balance and the secure delivery of electricity. Wind turbine proponents argue that the ‘wind carpet’ in the UK is stronger than in Germany. What wind turbine proponents never volunteer is that if the comparison is made between the wind carpet in the West Country and Northern Germany, which is where the turbines served by E-On are largely located, there is very little difference.

As a consequence of these unfavourable physical characteristics, it is not surprising that economics of wind turbine electricity generation are also unfavourable. The only way that the financial sums can be made to add up is through the ‘Renewable Obligation Certificates’ regime. Essentially, this is a requirement placed upon the electricity supply industry to purchase specified amounts of renewable energy at prices designed to give a return to the renewable energy producers. This becomes, in essence, a surcharge on every electricity bill.

Where does the balance lie?

RES, the developers, maintain that the balance of advantage tips heavily in favour of building the wind farm development in the Den Brook Valley. At the Planning Inquiry held in late 2006 the Planning Inspector agreed - however, that decision was quashed by the Court of Appeal and a new Inquiry is to be held.

It is our contention that the case for constructing 9 turbines in the Den Brook Valley has not been made by the developer. Throughout the whole of this application, it has proceeded by assertion rather than demonstration. We know calculations of Co2 savings have been accepted as wrong. We have seen errors in RES’s noise assessments and the Court of Appeal judgment stated that this was not the only point that is arguable.

At the end of the day, the only logical argument for constructing the turbines relates to the amount of electricity they will produce and hence the savings in greenhouse gases. Nowhere have we seen any data or analysis to demonstrate a conclusion that wind turbines in the Den Brook Valley would generate sufficient electricity to warrant accepting the many disadvantages that would result from their construction.

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