Nocton Fen Wind Farm - noise

Chapter 11 - Noise

Predicted LA90 (dB) Noise Levels for Nocton

I have tried to extract the relevant information relating to Nocton from the Preliminary Environment Information.

During constrained operation of the wind turbines (wind speed 8 metres per second), our village is predicted to encounter a range of 25 - 30 dB (see Vol 2: Fig 11.1). If the wind turbines were operating in unconstrained mode, I believe the predicted noise could be higher. That said, we encounter general background noise in any case during both day and night, so the predicted outputs will have to be measured against that for any potential impact.

I would think that night-time operation is the most likely time we might be aware of any noise from the wind farm. With World Health Organisation guidelines suggesting indoor limit values of 30dB LAeq and 45 dB LAfmax to avoid sleep disturbance, considering the range of 25 - 30 dB predicted, perhaps Nocton village will remain undisturbed. Perhaps not so for those residents living at Wasp's Nest!

Scottish Government Paper

'Technically, there are two quite distinct types of noise sources within a wind turbine - the mechanical noise produced by the gearbox, generator and other parts of the drive train; and the aerodynamic noise produced by the passage of the blades through the air. There has been significant reduction in the mechanical noise generated by wind turbines through improved turbine design.

The Report, "The Assessment and Rating of Noise from Wind Farms" (Final Report, Sept 1996, DTI), (ETSU-R-97) describes a framework for the measurement of wind farm noise, which should be followed by applicants and consultees, and used by planning authorities to assess and rate noise from wind energy developments, until such time as an update is available. '

http://www.gov.scot/Resource/0044/00440315.pdf

Chapter 11 - Extracts from Vattenfall's Preliminary Environmental Information

• Para 11.5.9: 'There is no specific guidance relating to the assessment of vibration from operational wind farms... it was agreed that vibration generated by the operation of the project is scoped out of the assessment.'
• Para 11.7.11: 'Low-frequency noise and vibration resulting from the operation of wind farms, together with the often associated subject of blade swish, are all issues that have been attracting an increasing amount of attention over recent years.'
• Para 11.12.5: '... depending on the levels of background noise, the satisfaction of the ETSU-R-97 derived limits can lead to a situation whereby, at some locations under some wind conditions and for a certain proportion of the time, wind turbine noise may be audible.'

ETSU-R-97 - The Assessment & Rating of Noise from Wind Farms

This report describes the findings of a Working Group on Wind Turbine Noise. The report is still being used today, despite it being released nearly 20 years ago.

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/49869/ETSU_Full_copy__Searchable_.pdf

ETSU-R-97 - An Alternative View - Dick Bowdler

'Born in Lincolnshire, I have lived in Scotland for over 30 years.'

Dick Bowdler contributed to the discussion document for the 'Good Practice Guide to the Application of ETSU-R-97 for Wind Turbine Noise Assessment', so his papers and publications may be of interest.

http://www.dickbowdler.co.uk/content/publications/ETSU-R-97_-_The_Alternative_-_Incl_figures.pdf

Papers and Publications - Dick Bowdler

http://www.dickbowdler.co.uk/content/publications/

A Good Practice Guide to the Application of ETSU-R-97 for the Assessment and Rating of Wind Turbine Noise

'This guide presents current good practice in the application of the ETSU-R-97 assessment methodology for all wind turbine developments above 50 kW, reflecting the original principles within ETSU-R-97, and the results of research carried out and experience gained since ETSU-R-97 was published. The noise limits in ETSU-R-97 have not been examined as these are a matter for Government.'

http://www.ioa.org.uk/sites/default/files/IOA%20Good%20Practice%20Guide%20on%20Wind%20Turbine%20Noise%20-%20May%202013.pdf

Wind Turbine Acoustic Pollution Assessment Requirements

This was a submission to the Scottish Government dated May 2011 from a campaign group.

http://www.scottish.parliament.uk/S4_EconomyEnergyandTourismCommittee/Inquiries/CATS_5.pdf

‘Bad science’ behind the wind turbine noise guidelines

'A cynic might well believe that ETSU‐R‐97 was produced to permit the introduction of wind farms into inappropriate low background noise locations where they and other comparable industrial installations could not meet planning conditions derived from the long established BS 4142. We will argue that noise assessments based on the long‐standing BS 4142 Standard provide a more robust methodology than ETSU.'

https://www.wind-watch.org/documents/bad-science-behind-the-wind-turbine-noise-guidelines/

Video from Swinford Wind Farm