Here at Cliscep some of us are keen to point out the disadvantages of wind turbines, by way of a counter-weight to the enthusiasm of those who fondly think that we can run a modern economy solely (or almost solely) on renewable energy. Regular readers will be familiar with my criticism of the UK’s reliance on infrastructure which is largely foreign-owned; which is environmentally unfriendly; which involves massive (and expensive) extensions to the National Grid to transport the electricity it generates in far-flung locations to the main areas of demand hundreds of miles away; which is intermittent and unreliable; which therefore relies on back-up rendered more expensive than necessary because of the subsidiary role it is condemned to play; which is increasingly supposed to rely on back-up in the form of huge (and potentially toxic) BESS, adding to the woes of those living near wind farms; which involves massive constraints payments when operators shut them down because the Grid can’t cope; and which, in the case particularly of offshore wind farms, are vulnerable to an attack on their cables to the mainland.

However, for those unfortunate enough to live near wind farms, there are other issues. The damage to the views and rural character of the neighbourhood is very real. Blade flicker can be a serious problem. And then there is the noise. Those who haven’t experienced it may suppose that turbines are quiet, but they aren’t. I have had the misfortune to walk beneath turbines in the Southern Uplands of Scotland, while hill-walking, and it was quite a scary experience. The noise they make is not insubstantial. That is probably why the ETSU-R-97 guidance was put in place by the UK government in 1996 (ETSU, by the way, stands for the Energy Technology Support Unit).

Last year the UK government produced a draft guide by way of an update. Given the extent to which wind turbines have proliferated – and are planned to multiply over the next few years – it probably made sense to re-visit the issue. Last year’s draft can be found here. Despite being an extensive document running to 49 pages, it made it clear that:

This draft guidance update does not represent a final position from government….Following this consultation, we will analyse responses and issue a formal government response….

And so it proved, for the UK government has now produced a final version which runs to 59 pages. There are some significant differences. For instance, in the Introduction, clause 1.2 of the draft said:

The technical guidance has been prepared by specialists on wind turbine noise (the ‘Project Team’)….The Project Team has also drawn on the experience of external peer reviewers. [my emphasis].

The final version of clause 1.2 has been subtly altered:

The technical guidance has been informed by advice from specialists on wind turbine noise (the ‘technical advisory team’) [my emphasis].

Unfortunately whoever was responsible for proof-reading the final draft didn’t notice that the specialists are no longer defined as the ‘Project Team’, but for some reason are now known as the ‘technical advisory team’ (possibly because their role seems to have been downgraded). And so it still says:

The Project Team has also drawn on the experience of external peer reviewers.

Has this subtle (or perhaps not so subtle) change made a difference? Well, the section dealing with cumulative noise (which is assuming greater significance in some locations, with more and more wind farm developments crowding in) commences at clause 2.34 in the draft. In some ways, this is one of the most important sections of the document. Clause 2.35 of the draft stated:

Where noise levels from the proposed development are lower than 27 dB LA90, or 10 dB or more below the total noise assessment criteria, a cumulative operational noise assessment is not necessary at that noise-sensitive receptor. All other wind farm developments must be considered in the cumulative assessment where their individual noise level contribution is greater than a level of 10 dB below the total noise assessment criteria. [my emphasis].

The equivalent clause in the final draft is clause 2.40. It is much larger, for the simple reason that it represents a watering-down of the protections to be offered to those adversely affected by the cumulative effects of wind-farm developments:

Where noise levels from the proposed development are lower than 25 dB, or 10 dB or more below both the day and night TNAC, a cumulative operational noise assessment is not necessary at that noise-sensitive receptor. In addition, the noise impacts of small wind turbines are generally localised and could represent a disproportionate constraint on larger wind energy developments. In such cases, the contribution of these turbines should be excluded from the cumulative noise assessment. For the purposes of this guidance, turbines with generating capacities of 50 kW or less can be considered to have localised noise impacts and can therefore be excluded from cumulative noise assessment. Turbines with generating capacities above 50 kW and less than (for example) a few hundred kilowatts can be excluded from cumulative assessment where it can be demonstrated that noise impacts from these turbines are localised and where including these turbines in a cumulative assessment would result in disproportionate constraints on larger developments. All other wind farm developments must be considered in the cumulative assessment where their individual noise level contribution is within 10 dB of the TNAC.

The eagle-eyed among you will have noticed that small wind turbines, and their effects, are now largely to be ignored. It seems that nothing must be allowed to operate as a “constraint on larger wind energy developments”.

Aileen Jackson, of campaign group Scotland Against Spin (SAS), tells me that small wind turbines, of the kind often used by farmers, demonstrate worse noise characteristics than large ones, due to their faster rotation speeds, making them sound like helicopters. Because of their smaller size, they receive little scrutiny in the planning system, compared to larger ones. Having set up SAS 16 years ago, after being surrounded by small farmers’ wind turbines (which proliferated when Feed-in Tariffs arrived on the scene) she feels as if this recent development has sent her back to Square One. And, very regrettably, she may be correct.

It seems that the UK government (aided and abetted by the SNP government north of the border) is fighting on all fronts to get what it – or what Mr Miliband – wants with regard to renewable energy developments. Enthusiasts for renewables might argue that this represents laudable determination and single-mindedness to drive through the agenda. Others, including myself, might consider it a worrying assault on human rights, which sits uncomfortably with a government headed by a human rights lawyer. Then again, the way things are heading, perhaps we won’t have to ponder that strange anomaly for much longer.