Night-time Lighting Assessment. Brian Denney, Environmental Planning Director Pegasus Group

Transcription

1 Brian Denney, Environmental Planning Director Pegasus Group

2

3 Contents: Introduction; Key Landscape and Visual Issues: Need For The Consideration Of Landscape And Visual Effects; Siting and Design Wind Farms in the Landscape, Version 3, SNH, February 2017; Visual Representation of Wind Farms, Version 2.2, SNH, February 2017 Visualisation Examples Importance of Correct Camera Settings Other considerations Key points

4 Introduction When do turbines require visible lighting? At and above 150m to blade tip (CAA Regs) Where otherwise requested e.g. MOD, proximity to airfields, flight paths What are the lighting requirements? 2000 candela steady red state on the nacelle and secondary light on the tower, just below the lowest extent of the blade tip. Must be visible at night, dusk and during low level light conditions during the day

5 Need for Consideration of Landscape and Visual Effects Assessments - What should be considered? Effects on Landscape Character Effects on Landscape Setting of Heritage Assets Effects on Visual Amenity Important to note it is not a Lighting Assessment or Lighting Impact Study and does not provide technical data

6 Need for Consideration of Landscape and Visual Effects Assessments When will they be required? Early engagement with Local Authorities and other Statutory Consultees required to discuss requirement. If required, must agree methodology to be used and set the scope limits of any assessment. Proportionality is key!

7 Need for Consideration of Landscape and Visual Effects What is the relevant L&V guidance? GLVIA (Third Edition). Siting and Design Wind Farms in the Landscape, Version 3, SNH, February 2017 (which now has some guidance on lighting). Visual Representation of Wind Farms, Version 2.2, SNH, February 2017 (paragraphs and ).

8 Siting and Design Wind Farms in the Landscape, Version 3, SNH, February 2017 What does the Siting and Designing guidance say? Where lighting is necessary, it should be designed to minimise landscape and visual impacts whist satisfying health and safety or navigation requirements. This may, for example, be achieved by incorporating shields so that the lights can only be seen from above; by lighting a reduced number of turbines; or by using lighting systems which are triggered by the proximity of aircraft.

9 Siting and Design Wind Farms in the Landscape, Version 3, SNH, February 2017 What does the Siting and Designing guidance say? Current experience suggests that the main landscape and visual effects are likely to include: lighting being visible over a considerable distance. The lights on the Beatrice offshore turbines, off the Caithness coast, are visible in clear conditions at distances of over 20 kilometres movement of turbine blades will create different effects depending on where the viewer is in relation to the wind farm. If the turbine blades pass in front of the light, a flashing effect as they cut across the light can occur. If the blades pass behind the light, there can be a striped effect as the light runs up the passing blades. In both cases these effects draw the eye to the turbines.

10 Siting and Design Wind Farms in the Landscape, Version 3, SNH, February 2017 What does the Siting and Designing guidance say? These effects are likely to be more significant in areas with less artificial lighting, including remoter rural locations, Wild Land Areas and dark sky sites where the absence of artificial lighting contributes to the feeling of remoteness or the direct appreciation of the night sky. Effects at dawn and dusk should also be considered where these could be significant.

11 Visual Representation of Wind Farms, Version 2.2, SNH, February 2017 What does the Visual Representation guidance say? It is difficult to illustrate turbine lighting well in visualisations, although some recent examples which use photographs taken in low light conditions (just before or after sunrise / sunset) have been more useful. Where an illustration of lighting is required, a basic visualisation showing the existing view alongside an approximation of how the wind farm might look at night with aviation lighting may be useful. Not all viewpoints will need to be illustrated in this way. The visualisation should use photographs taken in low light conditions, preferably when other artificial lighting (such as street lights and lights on buildings) are on, to show how the wind farm lighting will look compared to the existing baseline at night.

12 Visual Representation of Wind Farms, Version 2.2, SNH, February 2017 What does the Visual Representation guidance say? We have found that approximately 30 minutes after sunset provides a reasonable balance between visibility of the landform and the apparent brightness of artificial lights, as both should be visible in the image. It is important that the photographs represent the levels of darkness as seen by the naked eye at the time and the camera exposure does not make the image appear artificially brighter than it is in reality. The developer should attempt to formally agree the lighting requirements with the aviation authorities in advance of the application. Where this is not possible the visualisations should illustrate the lighting as described in the current legislation.

13 Visualisation Examples Dusk photograph 16:50 November 2016 Post sunset photograph 17:00 November 2016

14 Importance of correct camera settings Time f/1.4 1/40 seconds 8000 Iso Time f/9 4 seconds 250 Iso

15 Importance of correct camera settings Time f/9 2 seconds 250 Iso Time f/9 8 seconds 250 Iso

16 Other considerations What about Policy? Some recent and emerging policy in Scotland regarding this matter. South Ayrshire Councils Supplementary Guidance: Dark Sky Lighting (adopted August 2016). Scottish Borders Council Draft Renewable Energy Supplementary Guidance (December 2016), in which the Council consider that permanent night time lighting will be a major planning consideration to be addressed in terms of visual impact.

17 Key points: Early consultation with LPA and Statutory Consultees Assessment Methodology Photography Proportionality

18 Questions?

19