Launch of amplitude modulation discussion

The IOA has published today a discussion document on methods for rating amplitude modulation (AM) in wind turbine noise. The document proposes a definition of AM for wind turbine noise and describes a literature review of the available methods. From this, three methods are proposed for discussion. These describe: a time-domain method; a frequency-domain method and a hybrid method. Software will be made available shortly to allow those interested to rate samples of AM using these methods. The aim of the discussion document, prepared by the Institute's AM working party, is obtain feedback on the preferred methods.  After the consultation period, which ends on 30 June, the working group will set out its preferred method, which it plans to publish this autumn. A separate, Government-funded study is due to consider the subjective response and propose a penalty mechanism or threshold to be used when setting limits for wind turbine developments. To view the IOA discussion document and the accompanying questionnaire click here