SR Draft Response: Proposed updates to guidance on noise assessment of onshore wind turbines

Updated guidance for the assessment and rating of wind turbine noise

On July 4, DESNZ launched a consultation for the draft updated guidance on the assessment and rating of wind turbine noise.

Scottish Renewables and Renewable UK are working jointly on this response. Members are invited to send input to Heidi Douglas-Osborn and Jamie Blair.

This page provides a briefing on the Department for Energy Security & Net Zero's (DESNZ) consultation regarding updated guidance for the assessment and rating of wind turbine noise. The consultation will inform an update of the existing ETSU-R-97 guidance, published in 1996, which provides advice to Local Authorities across the UK for appraising planning applications for onshore wind developments. The draft updated guidance intends to align with advancements in turbine technology, scientific evidence, and government policies on noise and net-zero.

The technical guidance was prepared by a steering and peer review group of noise specialists, whilst technical experts from the wind industry provided support through workshops.

The consultation, which closes on August 29, 2025, seeks feedback on proposed updates to ensure that planning authorities have the best guidance for assessing noise emissions from onshore wind turbines, balancing opportunities for energy generation with potential noise impacts on residential amenity.

Here are the proposed changes outlined in the consultation:

• Aligning day-time and night-time noise criteria:
• The proposed approach instructs developers and planning authorities to select a single 'limit' from day and night background noise measurements.
• This single 'limit' will be the minimum of the day and night limit at each wind speed and will apply at all times.
• This change is recommended due to the potentially increased prevalence of Amplitude Modulation (AM) at night and the observation that the higher night-time limit is unusual compared to international practices.
• Raising the lower value for the day-time noise limit range:
• DESNZ proposes to raise the lower value for the day-time noise limit range from 35 dB to 37 dB, resulting in a new day-time range of 37-40 dB.
• While the night-time noise limit remains at 43 dB, it is anticipated that the single limit applied will often be defined by the day-time noise limit at most windspeeds.
• Approach to controlling amplitude modulation (AM):
• The consultation addresses the need for updated advice on assessing and controlling the impact of AM, which can manifest as a more pronounced "thudding" or "pulsing" sound from turbines.
• The previous guidance (ETSU-R-97) was deemed inadequate in controlling the impact of AM. The updated guidance aims to provide more comprehensive advice, building on prior government-commissioned research.
• Other technical guidance updates: views on this technical guidance are welcomed.
• Updated noise emission profiles: Descriptions of wind turbine noise emission profiles, wind speed references, and ranges have been updated to reflect evolutions in technology since 1996.
• Clarification on noise limit determination: Guidance on determining noise limits has been clarified to prioritise developments based on generation capacity.
• Interpretation of 'financially involved' receptors: Clarification is provided on how 'financially involved' receptors are interpreted for the application of noise controls.
• Cumulative impacts guidance: Further guidance has been developed on cumulative impacts, incorporating existing evidence and best practice advice.
• Example planning condition wording: Example planning condition wording and associated technical notes are provided to simplify planning controls.
• Character correction calculation: The method for calculating and combining character corrections has been defined.