Wind Turbines and Pylons: Guidance on Separation Distances

In response to the increasing number of planning applications for single wind turbines and small-scale wind energy developments - projects often below the threshold of formal wind farms but still with potential for significant visual impact - Gillespies was commissioned to develop new guidance for assessing their effects on residential visual amenity.

While the Guidelines for Landscape and Visual Impact Assessment (GLVIA3) provides a framework for assessing visual effects, there remains a lack of consistent national guidance for determining separation distances between wind turbines or pylons and residential properties. Current Welsh Government policy recommends that each case be assessed individually, leading to inconsistent approaches in planning decisions.

To address this gap, Gillespies developed a pioneering visual assessment tool tailored to small-scale wind turbine planning and other vertical infrastructure such as electricity pylons. This tool helps developers, planning officers, and local authorities to better understand and assess the landscape and visual impact of wind energy infrastructure on nearby homes.

The study introduced the innovative concept of residential visual amenity trigger distances, calculated using a mathematical formula to determine the apparent height and prominence of vertical structures from residential viewpoints. This empirical, evidence-based approach offers a more consistent, transparent methodology for evaluating the visual impact of onshore wind projects.

The methodology has been recognised for its contribution to the field of landscape planning and wind energy by winning a national Landscape Institute Award for Innovation in Landscape Planning in 2015. It has since been adopted as part of the evidence base for the Anglesey and Gwynedd Joint Local Development Plan and is being actively used to guide planning decisions on wind turbine applications across North Wales.

This project exemplifies Gillespies’ expertise in landscape and visual impact assessment (LVIA) for wind energy infrastructure and supports the development of low-carbon, renewable energy in a way that respects local landscape character and protects residential visual amenity.