Collision of science and sentiment – Waterloo wind farm cleared by EPA

The most interesting places on Earth are the subduction zones where tectonic plates of science and emotion scrape relentlessly. Buried in these dynamic boundaries we find the most telling insights into human nature. Wind energy spans the continents of science and sentiment, and discourse is dominated by this violent collision of empirical reality and unbridled passion.

Though living full time in this fissure might seem unenviable, I guarantee it is stirring. Yesterday, the plates grated once more, as the South Australian Environmental Protection Agency (SA EPA) released the long-anticipated results of their study into low-frequency noise levels at Waterloo Wind Farm.

First, some history. In May 2012, Graham Lloyd of The Australian mused in an article whether the Waterloo Wind Farm could be the culprit behind the mutations of chicken embryos, spikes in “sheep deformities” and “reports of erratic behaviour by farm dogs” – a joyful foray into absurdity that served as a textbook example of implication by proximity.

If it happens near a wind farm, it’s caused by a wind farm. Later in the year, a local resident near the Waterloo Wind Farm, Mary Morris, sent an email to a large group of residents living nearby. It strongly urged residents to issue formal complaints to councillors and government.

“All it has to be is a simple letter stating that the noise and vibration is causing a serious disturbance to sleep and rest, and/or that people are becoming sick – mention elderly and frail people AND children as well, especially if this applies to you”

Earlier this year, the SA EPA released two reports they’d commissioned from the acoustics firm Resonate. Respectively, they examined low-frequency and infrasonic noise emissions from wind farms, and compared them to other environments, such as the offices of the EPA. Resonate found that the levels of infrasound and low-frequency noise at wind farms were low, compared to the environments we’re exposed to regularly.

Yet, these were immediately deemed by wind farm opponents as irrelevant and insufficient – a consequence, I suspect, not of the EPA’s methodology but of their conclusions. Their prostrations centred around the theory that the EPA had measured only down to ten hertz, and used only a g-weighted scaling for infrasound measurements – something quite literally untrue.

When the study of low-frequency noise and infrasound at Waterloo wind farm was announced, it was largely supported by wind farm opponents. Graham Lloyd wrote “the Waterloo tests will provide information on what is really going on acoustically…[the SA EPA] will use very sensitive, and expensive, equipment to measure sound frequencies as low as 0.25 hertz”. Today Tonight covered the announcement of the study as well, focusing on the lowest frequencies measured. They also mention that the turbines will be turned on and off to assess the contribution of the machines to noise measurements.

At the end of the story, the host promises a follow-up once the results are released. The unironically-named ‘Stop These Things’ also praised the EPA for their choice to study Waterloo Wind Farm, and the ‘fine work done by journalists Graham Archer and Lucy Polkinghorne’.

The results were announced yesterday afternoon, at a town hall meeting in Clare. Their outcomes seem relatively clear:

“Where detectable, noise levels from the wind farm were found to comply with criteria in the EPA Wind Farm Environmental Noise Guidelines…..Background noise resulting from local winds and other noise sources, was shown to contribute to increases in low frequency noise that were comparable with, or higher than contributions from the wind farm”

Interestingly, the EPA found that residents were reporting noise issues from the wind farm during periods that the turbines were shut down:

“A ‘rumbling’ effect was found using diary records to focus the analysis, which could only be heard with amplification of audio records; however, in many cases, the EPA was unable to determine that described events could be attributed to the turbines; and at times reported events coincided with shutdowns of the plant”

That residents seemingly perceived noise they attributed to wind farms during a shutdown is difficult to reconcile with the claims of anti-wind groups.

The EPA also measured a large amount of ambient noise. For instance, at the West Site, “the noise environment was generally dominated by noise generated by wind acting on vegetation and by noise from other sources” and that “the noise contribution from the wind farm was too insignificant to be detectable”.

At times, the EPA were able to detect signatures of wind farm noise, but always at levels below the relevant criteria, and far from the amplitudes that might be required to cause Lloyd’s embryonic chicken mutations. It’s clear that residents may have been experiencing real noise issues, but they had been attributing these to the wind farm. I’d posit that the activities of wind farm opponents played a big part in this misattribution.

Sometime this year, the anti-wind lobby’s acceptance of the EPA’s study withered. In a pre-emptive post published on Monday, the anti-wind blog labelled the SA EPA ‘rotten’, ‘clowns’, ‘idiots’ and ‘bastards’. The content of the post, and a comment from ‘MM’, (presumably Mary Morris), theorises wrongdoing due to the placement of a microphone near a tree (if wind farm noise can be suitably masked by proximity to a tree, their problems are easily resolved by a requisite row of saplings). Apparently, two other acousticians, conducting measurements at the same time as the EPA and labelled ‘independent’ by wind farm opponents, had their microphones ‘away from the trees’.

This pattern, of demands trailed by livid, insult-ridden rejection, is precisely what can be expected from groups that are hoping simply to fill the gaps between a set of pre-ordained conclusions. The upcoming months of protestations and conspiracy theories will serve as an informative illustration of the frayed relationship between anti-wind groups and science. Logic rarely satisfies demands born of sentiment, and reality often fails to adhere to the rules set out by wind farm opponents.

The solution to the tricky problem of attempting to satisfy the concerns of residents whilst fending off the onslaught of misinformation from anti-wind groups lies somewhere deep in the subduction zone, where science and sentiment collide. Within this ever-churning fault line are the clues that will help us develop large-scale renewables that can meet the social, electrical and political demands of society.

Ketan Joshi is a Research and Communications Officer at Infigen Energy. He blogs here, and tweets here.