Technical specification IEC/TS 61400-11-2: measurement of wind turbine noise characteristics in receptor position - an overview

To facilitate the development of wind energy, a Technical Specification has been developed by the IEC project team PT61400-11-2, giving guidance on how to assess the noise characteristics from a wind farm in the surroundings through measurements and assessment at the receptor position. This includes physical characteristics like sound pressure levels, wind speed, amplitude modulation, tonality, amongst others. In writing the Technical Specification, the expert group intended to collect experience and knowledge from existing methods and standards. The TS is written as an operational guideline for conducting measurements for authorities and measurement institutes, tailored to the specific intentions of the measurements. It will be of particular interest in countries where no guidance on wind farm noise measurements is available but also in countries where guidance and legislation of environmental noise measurements may not be sufficiently adapted for wind turbine noise specifics. An overview of the content of the document will be presented along with the considerations and choices made during extensive discussions by the international expert group stemming from acoustic measurement institutes, wind turbine manufacturers, wind farm developer, site operators and academia.