Supporting Documentation - Renfrewshire Council

3.6 Visibility
Visual analysis of the proposed development is carried out in three stages:
1. Zone of Theoretical Visibility
2. Viewpoints
3. Visualisations
3.6.1 Zone of Theoretical Visibility
The Zone of Theoretical Visibility (ZTV) identifies where the proposed wind turbine can theoretically be
seen and gives a good indication of the broad area this visibility extends too. The ZTV represents visibility
as though the ground surface was bare, not considering screening from trees, buildings etc. The earth
curvature and refraction of light affect the visibility over a great distance. This was not calculated during
the ZTV for the farm which means the visibility will be over calculated.
As recommended, in the SNH Visual Representation of Wind Farm report, for a turbine height of 45.9m to
the tip, the ZTV distance of 15km was used from the centre of the turbine. The target height (turbine) was
taken to be centred over the base of the wind turbine. The Hub and Blade Tip Zone of Theoretical
Visibility map is shown in Appendix H. Visibility is constrained from the North East and South of the
turbine. Potential visibility extents North and West with the hub being visible 15km away. Just because a
development is seen does not mean it is a significant visual impact.
The SNH Visual Representation of Wind Farm report states that at 10km from a turbine, the nacelle detail
cannot be identified. At 15km, the blade movement would be unnoticed to a casual observer.
Taking the above note into account, along with the ZTV results illustrated in Appendix H, the properties in
close proximity of the turbine will evidently have the most prominent view of the turbine. However, it is
anticipated that the visibility of the wind turbine will not generate a substantial concern to the visual impact
of the local community and out with.
3.6.2 Viewpoints
Viewpoints are selected places from which the proposal may be seen. Viewpoints are used to assess the
existing visual resource, sensitivity of this resource to wind development, and predicted appearance of
the final proposed development.
A viewpoint can be representative or specific. A representative viewpoint illustrates a range of views that
will see the proposed development. Specific viewpoints are views from a specific location, such as local
visitor attractions, settlements, routes valued for their scenic amenity and places with cultural landscape
association.
Three viewpoints were selected as part of the visual analysis. Their locations are shown in Appendix G.
A photograph was taken from each point towards the proposed turbine position representing the existing
view from this location. Further visualisations were carried out as explained below.
As can be seen in the visualisations, the view of the turbine location from each of the viewpoints proves
not to be intrusive.
3.6.3 Visualisations
Visualisations are illustrations that represent the observer’s view, from the above viewpoints, of the
proposed wind turbine, such as photomontages, wireframes and photographs.
Waterman Group, Renewable Energy, 2/4 Canning Street Lane, Edinburgh, EH3 8ER T:0131 221 7020
16
K:\Projects\CIV12920_ILI Windfarms_Batch 7\CIV12920_XXX_Hartfield
Farm\Documents\Reports\CIV12920_1202xx_Hartfield_Supporting Turbine Assessment_225kW.docx