14 INFRASTRUCTURE, TELECOMMUNICATIONS & SHADOW FLICKER

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1 Knockskae Wind Farm Environmental Statement Volume 2 Main Report INFRASTRUCTURE, TELECOMMUNICATIONS & SHADOW FLICKER 14.1 Introduction This Chapter has been prepared by. It identifies and assesses the potential effects that the construction and operation of Knockskae Wind Farm (the Development) may have on infrastructure and telecommunications assets within the study area and predicts the potential for shadow flicker effects that may occur at neighbouring dwellings. Appropriate mitigation and compensation measures are described that will be implemented to prevent, reduce or offset potential adverse effects Consultation has been undertaken with relevant operators to confirm the location of potentially affected infrastructure assets and telecommunication links and to confirm the extent of their required separation distances between the wind turbines and their interests. The location of infrastructure assets and telecommunication links are taken into account during the site design process to ensure the operations are not adversely affected. The Development is designed around these constraints which ensure that possible effects have been appropriately mitigated to an acceptable level The whole of the UK has switched to digital television transmission. Digital signals are less susceptible to degradation and interference from wind turbines compared to the old analogue system and will only occur in specific instances. As such a detailed assessment has not been undertaken but Television reception will be monitored during development, and any issues will be mitigated as necessary Under certain combinations of geographical position, time of day and year, wind speed and wind direction, the sun may pass behind the rotor of the wind turbine and cast a shadow over neighbouring buildings windows. When the blades of the wind turbine rotate, and the shadow passes a window, to a person within that room the shadow appears to flick on and off; this effect is known as shadow flicker. It occurs only within buildings where the flicker appears through a window opening and only buildings within 130 degrees either side of North relative to a wind turbine can be affected. It is possible to calculate the number of hours per year that shadow flicker may occur at a building from the relative position of the turbine to the building, the geometry of the wind turbine, the latitude of the wind farm site and the width of the windows potentially affected The wind turbines at the proposed wind farm will operate at around 6 to 20 revolutions per minute (rpm). Given the turbine will have three blades, the frequency at which a blade will pass a particular point will be in the order between 18 and 60 times a minute which equates to between 0.3 and 1.0 flashes per second (hertz). This is significantly less than the 2.5 and 30 hertz frequency range generally thought to induce photosensitive epilepsy. Therefore the issue of photosensitivity epilepsy is not considered further in this assessment as there are no predicted adverse health effects Shadow flicker can however still present a nuisance to amenity where people are within the rooms affected by the phenomenon. In order to quantify this effect, it is possible to calculate the number of hours per year that shadow flicker may occur at a window. The specialist computer software 'Wind Pro' was used to quantify the levels of potential shadow flicker associated with the proposed Development Methods Scope of Assessment The aim of this assessment is to identify existing infrastructure assets and telecommunication links in the vicinity of the Development and to establish appropriate separation zones around these interests with their operators, to ensure the Development is designed in such a manner to avoid any effects on their interests. Where effects are unavoidable, appropriate mitigation measures are agreed so that any residual effects are acceptable The aim of this section is to quantify the predicted level of shadow flicker that could be experienced by any affected dwellings. Assessment Guideline or Guidance and Methods Planning guidance is contained within the Scottish Government Specific Advice Sheet for Onshore Wind Turbines, This document states, with regards to infrastructure and telecommunications: Wind turbines produce electro-magnetic radiation which can interfere with broadcast communications and signals. The Radiocommunications Agency (RA) register of all civil radio communications installations in the UK can identify any radio installations in the neighbourhood of a wind farm site, but will not identify their owners. Applicants should make direct contact with any authorities or bodies likely to have an interest, in particular, the local emergency services, local authority services departments, gas and electricity companies There is no specific standard for the assessment of shadow flicker in the UK and no guidelines on acceptable levels of shadow flicker, although the Advice sheet states: Under certain combinations of geographical position, time of day and time of year, the sun may pass behind the rotor and cast a shadow over neighbouring properties. When the blades rotate, the shadow flicks on and off; the effect is known as "shadow flicker". It occurs only within buildings where the flicker appears through a narrow window opening. The seasonal duration of this effect can be calculated from the geometry of the machine and the latitude of the potential site.

2 Knockskae Wind Farm Environmental Statement Volume 2 Main Report 14-2 Where this could be a problem, developers should provide calculations to quantify the effect. In most cases however, where separation is provided between wind turbines and nearby dwellings (as a general rule 10 rotor diameters), shadow flicker should not be a problem. However, there is scope to vary layout and/or reduce the height of turbines in specific cases. Significance For electromagnetic interference, assessment of the proposed Development will be based upon whether there is a direct interference. Since this effect is either present or absent it is not considered appropriate to define sensitivity, magnitude of change, or significance. Either the Development has to be designed in such a manner to avoid any detrimental effects or appropriate mitigation has to be agreed so that any residual effects are acceptable Similarly, in relation to shadow flicker, it is not considered appropriate to define sensitivity, magnitude of change or significance. The layout is designed to minimise the potential for shadow flicker occurrence and a commitment is made to investigate complaints and mitigate shadow flicker should the effects prove detrimental to the amenity of affected dwellings. Approach to the Assessment The Independent regulator and competition authority for the UK communications industries (OFCOM) was consulted to identify the operators of any links that may need to be considered in the design of the Development Consultation was then undertaken with the operators and infrastructure service providers to obtain details of any infrastructure at or surrounding the Development and to establish the necessary separation requirements The Scottish Government Specific Advice Sheet for Onshore Wind Turbines states that shadow flicker will not be a problem if the nearby dwellings are at a separation distance of 10 rotor diameters from a wind turbine The study area has therefore been limited to 870 metres (m) around the proposed turbine locations based on a rotor diameter of 82 m plus a +/- 50 m micrositing allowance. Buildings located outside 130 degrees each side from north were excluded from the analysis as no path between the sun, the turbine and these buildings resulting in shadow flicker will occur. The buildings included in this analysis are shown on Figure The likelihood of shadow flicker occurring and the duration of such an effect depends upon the following factors: The direction of the building relative to the turbine(s); The distance from the turbine; The turbine hub-height and rotor diameter; The frequency of bright sunshine and cloudless skies (particularly at low elevations above the horizon); and The prevailing wind direction The calculations assume a worst case scenario including the following assumptions: The sun always shines in a clear sky i.e. no account of climatic conditions (such as clouds or precipitation) has been made; Objects surrounding the windows that may block the view to turbine such as trees have been disregarded; The turbine rotor is always aligned face-on to the window, providing the maximum opportunity for shadow flicker; and The rotor is always turning, i.e. no account has been taken of calm or shut-down periods When the sun is close to the horizon, at dawn and dusk, the intensity of the sun s rays is reduced and is less likely to cast distinct shadows. It is generally considered that when the sun is lower than 3 degrees above the horizon, that shadow flicker is unlikely to occur to any significant extent. This parameter has been included in the calculations. Summary of Site Surveys No site surveys were undertaken relating specifically to or. Summary of Relevant Planning Policy Relevant overarching planning policies for this Development are detailed in Chapter 5 Planning Policy Context. The following national, regional and local Planning Policies are relevant when assessing Infrastructure, Telecommunications and : Scottish Government, Online Renewables Advice for Onshore Wind Turbines. (October, 2012). South Ayrshire Council, South Ayrshire Local Development Plan, The Scottish Government advice sheet states that applicants should make direct contact with any authorities or bodies likely to have an interest, in particular, the local emergency services, local authority services departments, gas and electricity companies The wake downwind of a wind turbine could have significant effects on overhead line conductors, potentially causing increased levels of motion and, in extreme cases, conductor clashing. Research by National Grid and other international bodies has shown that at distances greater than three rotor diameters from the turbine, wake effects are negligible. This stand-off distance (or buffer) has been used on all high voltage power lines during the design of the Development. The time of year; The proportion of day-light hours in which the turbine operate;

3 Knockskae Wind Farm Environmental Statement Volume 2 Main Report 14-3 Summary of Consultation A Scoping Report was issued to South Ayrshire Council on 28 July 2014 for comment on the outlined methodology of the Environmental Impact Assessment (EIA). Relevant responses from consultees relating to this report are summarised in Chapter 4 Summary of Consultation Consultation has been undertaken with a number of service providers to confirm the location of any potentially affected infrastructure assets and telecommunication links. Details of contacts are listed below, each of which were provided the wind farm location and land available for associated infrastructure. Independent regulator and competition authority for the UK communications industries (OFCOM); Scottish Water; Scottish and Southern Energy Plc (SSE); Scottish Gas Network (SGN); Scottish Power; Virgin Media; British Telecom (BT); Arqiva (BBC ITV); Atkins Ltd; and Joint Radio Company (JRC) Existing Conditions The initial consultation identified a number of telecommunication links and infrastructure assets that are within the vicinity of, or intersect the Development boundary. Details of these can be seen below in Table Table 14.1 Summary of Consultation Service Provider Date Response Received Response BT 15/04/2013 BT have identified a link within the vicinity of the Development, however it does not intersect the Development area. A clearance distance of 100m from blade tip to link path is required and has been applied. This clearance distance is derived from the blade radius (41m) plus 100m. Arqiva (BBC ITV) 17/05/2013 The Development is unlikely to affect any of the Re-Broadcast Links (RBLs). Regarding microwave links Arqiva has no issues with this proposal. Atkins Ltd 15/04/2013 Atkins have no objection to the proposal. JRC 30/04/2013 The proposal is cleared with respect to radio link infrastructure operated by Scottish Power and Scotia Gas Networks A number of low voltage overhead cables, have been identified within the vicinity of the site, one of which intersects the Development boundary. The Energy Network Association (ENA) recommends a minimum stand-off distance of topple + 10%, which in this case is 139m Arqiva, responsible for providing the BBC and ITV's transmission network, is responsible for ensuring the integrity of Re-Broadcast Links (RBL's). Their analysis shows that the proposed wind farm is unlikely to affect any of their RBLs. The nearest RBL is Kirkmichael Details of all infrastructure and telecommunication assets are displayed on Figure 14.2, with the appropriate stand-off (or buffer) distances applied. Table 14.1 Summary of Consultation Date Response Service Provider Received Response Figure 14.1 illustrates the footprint of potential shadow flicker occurrence within the study area of 870m from the turbines (see Section ). Within this area there are no dwellings that could be affected by. OFCOM 13/04/2013 Links found. OFCOM advise consulting with BT. Scottish Water 04/02/2013 Scottish Water has no objection to the Development. SSE 16/04/2013 SSE do not have any network records within the area requested. They advised contact with Scottish Power Distribution (see below). SGN 18/04/2013 Scotland Gas Networks has no gas mains in the area of enquiry. Scottish Power 16/04/2013 A number of overhead and underground cables have been identified within the vicinity of the site. An 11kV overhead cable intersects the western edge of the development boundary Potential Effects The impact on telecommunication links during the construction and decommissioning phase will be negligible as any disturbance to electromagnetic interference (EMI) will commence only when there is a physical obstruction to the telecommunication link and television signal All wind turbines have been sited away from the identified infrastructure detailed in Table 14.1 and their associated stand-off or buffers, and therefore there is no significant impact predicted on these assets during the operational phase of the Development.

4 Knockskae Wind Farm Environmental Statement Volume 2 Main Report There are no dwellings that could be affected by shadow flicker within the 870m study area; therefore there are no potential effects during construction, operation or decommissioning of the Development Mitigation There are no mitigation measures currently required or proposed, but will continue to engage with service providers to ensure the proposed Development will not cause any effects to their infrastructure will continue to engage with Scottish Power to ensure the proposed Development will not cause any effects to their infrastructure. Detailed pre-construction consultation will be undertaken to ensure any potential impacts on the infrastructure assets during construction are identified and mitigated, and that safety is maintained at all times A range of technical solutions are available in the event that television interference is identified as a result of the proposed Development. These may include improvement of receiving aerials or provision of affected households with an alternative source of television signal There are no dwellings that could be affected by shadow flicker within the 870m study area; therefore there are no residual effects predicted during construction, operation or decommissioning of the Development Cumulative Effects The impacts on infrastructure and shadow flicker are local to the Development and therefore no cumulative impact will be experienced Summary A number of low voltage overhead cables have been identified within the vicinity of the site, some of which intersect the western edge of the Development boundary. All wind turbines have been sited away from these assets; therefore there is no significant impact predicted will continue to engage with Scottish Power to ensure the proposed Development will not cause any effects to their infrastructure No mitigation measures are proposed, this will however be kept under review during the operation of the scheme in case particular combinations of circumstances arise that increase the potential for disturbance (particularly where rooms affected are in regular occupancy and the unlikely effect proves to be a frequent occurrence in reality) If this situation arises then standard shadow flicker controllers will be installed on turbines to shut them down when all parameters needed to cause shadow flicker are present, thereby eliminating any shadow flicker issues Residual Effects It is proposed that should an unforeseen effect arise a requirement for remedial action by the developer would form part of the planning conditions In the unlikely event that television reception at local dwellings is adversely affected by the Development, will commit to appropriate mitigation measures, which could be secured by way of a planning condition No mitigation measures are considered necessary during decommissioning of the Development There are no dwellings within the 870m study area that require assessment for shadow flicker. It is therefore predicted that there will be no impact from shadow flicker by the proposed development References South Ayrshire Council, South Ayrshire Local Development Plan, 2014 Ayrshire Joint Planning Unit, Ayrshire Supplementary Planning Guidance: Wind Farm Development, 2009 South Ayrshire Landscape Wind Capacity Study: Main Study report (2013) Energy Networks Association. (2012). Separation between Wind Turbines and Overhead Lines, Principles of Good Practice. National Society for Epilepsy (2002) Information on Epilepsy: Photosensitive Epilepsy Scottish Government, Online Renewables Advice for Onshore Wind Turbines (October, 2012). Scottish Government, (2014). Scottish Planning Policy The impacts to existing infrastructure can be technically mitigated prior to or following construction and therefore no significant effects are anticipated.

5 Scale: A3 Designer: SM km Ordnance Survey Crown Copyright, All rights reserved Licence number Checked: LK Approved: DR accepts no responsibility, and denies any liability whatsoever, to any party that uses or relies upon this drawing without 's express written consent. Do not scale this document. 11 This drawing has been produced for the use of 's client. It may not be used, modified or relied upon by third parties, except as agreed by or as required by law. Project Management Initials: RV F PROJECT KNOCKSKAE WIND FARM CLIENT KEY: Turbine Location Planning Application Boundary Study Area PROJECT NUMBER Figure 14.1: Potential Shadow Flicker Occurrence SHEET NUMBER SHEET TITLE 1 of 1

6 Scale: A km Ordnance Survey Crown Copyright, All rights reserved Licence No accepts no responsibility, and denies any liability whatsoever, to any party that uses or relies upon this drawing without 's express written consent. Do not scale this document. 11 This drawing has been produced for the use of 's client. It may not be used, modified or relied upon by third parties, except as agreed by or as required by law. Project Management Initials: RV Designer: SM Checked: LK Approved: DR F PROJECT KNOCKSKAE WIND FARM CLIENT KEY: Turbine Location Planning Application Boundary Access Track Extent of Other Site Infrastructure ( Ò Temporary Meteorological Mast Link Identified by BT Link Identified by BT - 141m Buffer Scottish Power Transmission Assets 11kV Overhead Cable 11kV Underground Cable Low Voltage Overhead Cable Low Voltage Underground Cable Low Voltage - 139m Buffer PROJECT NUMBER SHEET TITLE Figure 14.2: Radio Communication Links and Infrastructure SHEET NUMBER 1 of 1