Environmental Statement South Kyle Wind Farm August 2013

Transcription

1 19 AVIATION, RADAR, INFRARED LIGHTING AND ELECTROMAGNETIC INTERFERENCE (EMI) Aviation and Radar Executive Summary Introduction Approach Potential Effects Mitigation Conclusion Impact of IR Lighting on Galloway Forest Dark Sky Park Microwave Communication and UHF Scanning Telemetry Television Reception... 8 Volume 2 of 5 Chapter 19 Aviation, Radar and EMI Page 1 of 9

2 19 AVIATION, RADAR, INFRARED LIGHTING AND ELECTROMAGNETIC INTERFERENCE (EMI) 19.1 Aviation and Radar Executive Summary 1 Wind farms have the potential to interference with electromagnetic signals used for navigation and communication, including radar. This section provides an assessment of the potential impacts that the proposed South Kyle Wind Farm may have on radar systems and aviation interests. 2 Both military and civil aviation stakeholders have been consulted during the development of the wind farm in order to identify potential impacts and agree the most appropriate approach to mitigation. Contact with statutory consultees has been informative and constructive. 3 The design of South Kyle has taken careful consideration of potential radar impacts and opportunities for mitigation as offered by a number of emerging technologies. South Kyle design consisting of 50 turbines concentrates 15 turbines in the southern area of Kyle forest and the remainder of 35 turbines on land known as Brownhills which is located further south of Kyle forest. 4 Line of Site (LoS) modelling has established that whilst a number of turbines will be terrain shielded from Air Traffic Control (ATC) radar at Prestwick and National Air Traffic (NATS) En Route radar at Lowther Hill. It is anticipated that the majority of the turbines proposed will have the potential to impact upon the interests of Glasgow Prestwick Airport (GPA) and NATS. 5 Work undertaken to date with the aforementioned Air Navigation Service Providers (ANSP s) indicate the turbines which will be in radar line of site have the potential to be mitigated subject to formal approval of the ANSP. Vattenfall, GPA and NATS believe this can be secured by the imposition of a suitably worded planning condition. 6 The Ministry of Defence (MoD) ensure physical safeguarding of low flying routes and the potential for vibration detection at the Nuclear Test Monitoring Station at Eskdalemuir. The location and design of South Kyle has not raised concerns in either case. Infrared lighting maybe requested by the MOD and can be secured by way of a planning condition Introduction 7 Wind turbines have the potential to interfere with electromagnetic signals used for navigation and communication, including air traffic control (ATC) radars and, if detected, have the potential to affect the provision of air traffic services (ATS). The most common cause for concerns is their potential effect on primary surveillance radar (PSR). PSR is used by many civil and military aerodromes and by NATS. A description of these effects can be found in the Civil Aviation Authority Directorate of Airspace Policy (DAP) Civil Aviation Publication (CAP) 764: CAA Policy and Guidance on Wind Turbines. Volume 2 of 5 Chapter 19 Aviation, Radar and EMI Page 2 of 9

3 8 Wind turbines also have the potential to impact air traffic as a physical obstruction when located close to aerodromes due to the height limitations as described in aerodrome safeguarding plans. 9 Both wind power and aviation are important to the UK s national interests and it is important that they co-exist in a safe manner Approach 10 The approach we have taken so far and will continue to take will be: engage stakeholders prior to submission of the S36 application to Scottish Government agree potential mitigation prior to determination continue to work on reaching formal agreements of mitigation with stakeholders post submission once mitigation is agreed, agree a planning condition that allows the project to progress should planning be consented 11 The decision to progress the South Kyle proposal has been significantly influenced by the work of the South West Scotland Radar Study led by Scottish Government. As the work of the group progressed Vattenfall gained confidence radar mitigation for South Kyle as situated within the Prestwick arc would have a reasonable prospect of mitigation being successfully implemented. Vattenfall understands that any radar mitigation will require safety case approval to the satisfaction of the Civil Aviation Authority (CAA). Vattenfall has always understood that engagement with ANSPs is vital to ensure proposed mitigation can be delivered. The ANSP will play a key role production of an associated safety case and the agreement of the most appropriate mitigation solution Potential Effects NATS En-Route (NATS) 12 During development of the wind farm layout NATS safeguarding were consulted to determine the potential impact on the radar facility located at Lowther Hill. Vattenfall requested NATS to undertake Line of site modelling, to validate the modelling results held by Vattenfall. NATS report indicated at that time the majority of the South Kyle turbines would benefit from terrain shielding. However without mitigation the visible turbines would be likely to cause an impact on NATS operations, resulting in a compromised service. 13 As the site has developed and turbine locations modified to address landscape impacts and other site constraints it became clear that a radar mitigation for NATS would be a key element of the proposed project. Regular discussions and meetings with NATS have been on going over many months. 14 Vattenfall employ an aviation manager who has ensured that opportunities to develop mitigation for NATS are considered fully. Vattenfall are active in a number of initiatives involving NATS both with the backing of Renewables UK and one off projects specific to Vattenfall s assets. There is a clear Volume 2 of 5 Chapter 19 Aviation, Radar and EMI Page 3 of 9

4 commitment of both Vattenfall and NERL to reach agreement on the most appropriate mitigation for South Kyle Glasgow Prestwick Airport (GPA) 15 The radar line of sight (LoS) visibility model has been a useful tool in advising the development of South Kyle. Although there is some terrain shielding from Lowther Hill as mentioned above the proposal will benefit from very little terrain shielding in terms of radar LoS towards GPA. It is clear that radar mitigation will be required to satisfy both ANSP s. 16 Vattenfall have attended a series of meetings with GPA, their scoping response referred to meetings held at that time to discuss concerns of potential radar impacts and are summarised below: a. Much of the area of interest is visible to our Primary Surveillance Radar, allowing the potential for turbines to generate radar clutter. b. South Kyle is located under an area of our controlled airspace in a key area for marshalling aircraft onto final approach for Runway 31. c. We anticipate that a radar mitigation will be required for this proposal. 17 GPA highlighted their intention to continue to engage with Vattenfall to fully assess the potential impact on our operation. 18 Recognition was also given to the need to develop a regional solution to mitigate the aviation impacts of a number of wind farms in this region and South Kyle would be a potential beneficiary of this scheme. At that time a potential solution was still in its infancy. 19 Radar mitigation has been a key determining factor in the progress of South Kyle. The prospect of aviation mitigation has been an important area of focus for developers, ANSP s and consenting bodies such as the Scottish consents unit. To determine the best way forward a group was formed led by the Scottish Government and included all involved parties including GPA, NATS, MOD and Vattenfall amongst other active developers who sought a solution to potential radar impacts in this region. 20 Prior to the formation of the South West Scotland Regional Aviation Solution Group (SWSRASG) a number of solutions had been progressed in isolation but the formation of the group helped galvanise efforts with all relevant parties involved. 21 SWSRASG was set up in 2009 to investigate the potential for the application of blanking/in-fill solutions, due to the significant number of megawatts (MW) held up in South West Scotland. Vattenfall had taken an active interest and involvement in the work of this group along with other developers. Turbine coordinates were fed into the study group to help define an area of potential mitigation. One aspect which evolved during this process was the potential of a solution to those developments which had the greatest impact on GPA. Progress of sites within this area were actively managed by GPA and this area was labelled as the Prestwick Arc. Volume 2 of 5 Chapter 19 Aviation, Radar and EMI Page 4 of 9

5 22 During development of the SWSRASG mitigation work, South Kyle was modelled using a group of turbines in an area larger than that proposed in this submission. During the active life of the group a number of fly over exercises of potential wind farm sites helped define the Prestwick Arc, which continues to evolve with South Kyle occupying a central area within the arc. It is clear that emerging technologies offer a number alternatives for ANSP s to evaluate. Vattenfall along with other developers have seen the Arc change shape as GPA has engaged with a number of potential mitigation providers, however it may be noted that South Kyle continues to occupy a central area within the arc Ministry of Defence (MoD) 23 South Kyle is located outside the area defined as having potential to impact on the Eskdalemuir detection array, therefore the only potential issue with MoD is that the turbines could cause a physical obstruction for low flying aircraft. 24 During the development of the wind farm layout the MoD were given the opportunity to review the design and advised Vattenfall that there would be no impact to their operations, their full approval is subject to the review of final design. 25 MoD will provide a final formal response upon submission of this planning application. Infrared aviation lighting maybe requested, which can be secured by way of an appropriate planning condition Mitigation NATS En-Route (NATS) 26 NATS have stated that there is mitigation possible at South Kyle by using current operational infrastructure in the area to mitigate the affects. 27 The mitigation is to take radar data from a separate PSR that see s the airspace above the turbines but isn t impacted by the turbines due to terrain shielding. This data is then provided to NATS to be fed into their Multi Radar Tracking (MRT) system in order to remove the returns caused by the turbines Ministry of Defence (MoD) 28 The Ministry of Defence (MoD) have considered the potential impact to low flying aircraft and has provided advice to support the development s design. The purpose of military low flying in the area of South Kyle is for fast jets to evade radar detection and the aircraft fly in formation along the valley floor. The turbines for the proposed South Kyle development have been sited in a manner to mitigate this impact so the MoD has advised that the design does not impact upon their operations. 29 It is standard practice for Low Flying Aircraft that the MoD may request the development is lit with Infra Red (IR) lighting at a specified number of turbines and are likely to be located at the nacelle. Volume 2 of 5 Chapter 19 Aviation, Radar and EMI Page 5 of 9

6 30 The IR lighting will be visible to pilots wearing Night Vision Goggles (NVGs) but not visible to the human eye Glasgow Prestwick Airport (GPA) 31 There are several options under consideration to mitigate the potential impact on GPA s PSR from both South Kyle and other wind farm developments in this region of Scotland. The most appropriate mitigation is best determined when an assessment of competing technologies is considered along with the preference of GPA to secure a common solution. At the time of writing six competing technology providers are involved in ATC trails close to an operational Vattenfall wind farm and further companies not shortlisted are active in promoting solutions. 32 In addition to the potential options for mitigation are currently being trialled in the UK. The owners of GPA and Vattenfall are working together to assess the suitability of their equipment in this environment. These technologies vary from infill radars, which involve merging of radar data, to new radar systems which aren t impacted by turbines. 33 Although processing out the effects of turbines is preferred, modelling work has confirmed that it would be possible to install a PSR in a location which would use the terrain to shield the turbines from itself yet keeping the low level coverage the airport requires for its operations. The data from this PSR could then be merged with the airports PSR to remove the affected area and replace it with clean airspace. 34 GPA has advised that they have invested a great deal of time and expertise in trying to develop a regional solution for wind farms in this region which Vattenfall and other developers appreciate and support. GPA has submitted correspondence to support this application which confirms GPA s engagement with Vattenfall to seek the most appropriate mitigation for the potential impacts of South Kyle (see Appendix 19.1, Volume 5) Conclusion 35 Both military and civil stakeholders have been consulted during the development of South Kyle. Vattenfall has sought to update them on the proposed development area, gain feedback on design and identify appropriate mitigation as described above. A range of mitigation options are believed to be available for NATS and GPA. Vattenfall expects to receive initial holding objections from these two ANSP s once consultation begins, all parties are expected to reach agreement on a form of words which will protect the interests of the ANSP whilst supporting the most effective delivery of renewables. This will enable all parties to reach a common agreement to ensure a commitment to mitigation before turbines are erected therefore mitigating any potential impacts to the stakeholder. 36 Vattenfall are committed to working with all aviation stakeholders to ensure aviation safety is not compromised and consented schemes are progressed in a timely manner. Volume 2 of 5 Chapter 19 Aviation, Radar and EMI Page 6 of 9

7 19.2 Impact of IR Lighting on Galloway Forest Dark Sky Park 37 As described above, following discussion with the MoD it has been agreed that a selected number of the 50 turbines proposed for the South Kyle Wind Farm will require IR aviation lights. South Kyle lies 6km east of the edge of the buffer zone for the Gold Tier Dark Sky Park centred on the Galloway Forest Park. In June 2013, Vattenfall commissioned a study by Dr Stuart Lumsden (School of Physics and Astronomy University of Leeds) to consider the direct and scattered light, from both the proposed aviation lights and other sources which will be seen from both the Core Zone of the Dark Sky Park, as well as regions in the Buffer Zone (including the recently opened Scottish Dark Sky Observatory). 38 The report which has been included in this submission as Appendix 19.2 (Volume 5) highlights that the proposed IR aviation lights at South Kyle Wind Farm will have no significant effect on the Galloway Forest Dark Sky Park for any user. Nor will the proposed lights affect the Gold Tier status of the park, since the lights are (i) infrared and (ii) allowed within the context of the regulations of the Dark Sky Association. Casual tourists will not suffer any loss of amenity from the darkness of the sky at Galloway Forest Park and its surroundings as they will not be able to see the lights Microwave Communication and UHF Scanning Telemetry 39 Consultation has been undertaken with the Office of Communications (Ofcom), the Joint Radio Company (JRC) and Atkins, all of whom manage microwave communications and UHF Scanning Telemetry links owned and operated by third parties. A summary of the responses received is presented in the table below. Consultee Summary of response Action Ofcom Identified one fixed link in the search area requested and provided details of the link operator which is BT. BT Atkins JRC Provided details of one link that is located on the edge of the search area. They require a 100m clearance from blade tip to link path. The search area was examined in relation to UHF Radio Scanning Telemetry communications used by Atkins Client (Scottish Water) in the region and they have no objection to the proposal. The search area was examined in relation to radio link infrastructure operated by:- Scottish Power and Scotia Gas Networks and they have no objection to the proposal See action relating to BT. The distance between the blade tip to link path is approximately 2.3 km N/A N/A Volume 2 of 5 Chapter 19 Aviation, Radar and EMI Page 7 of 9

8 40 Through this process, details of microwave communications links were collated. Each of the operators who responded provided details of the frequency of the links and associated clearance distances sought from turbines. The details formed constraints that were incorporated into the iterative design process detailed in Chapter 3: Site Selection and Constraints of this ES. Through the process of consultation and design, the paths of known links for which details were provided have been avoided Television Reception 41 Wind turbines have the potential to adversely affect domestic television reception through either physical blocking of the transmitted signal or, more commonly, by introducing multi-path interference where some of the signal is reflected through different routes. Multi-path interference to television signals can cause ghosting on older analogue transmissions where an object in the picture appears several times in slightly different positions. 42 Within the UK, television signals are undergoing a switch from analogue to digital transmission, with analogue signals being turned off. The development lies within the STV Central television region which has completed its switch to digital transmission and transmitters serving this region no longer transmit analogue signals, and therefore ghosting is not considered an issue. 43 Digital television signals are not generally affected by wind turbines, however, a minimum signal strength is required for digital television to operate effectively. If a property already receiving a weak digital signal experiences additional blocking or reflections from wind turbines, the signal level may drop, causing the television to pixelate or cut out intermittently. Reflections and blocking from other objects (such as trees) close to the aerial can cause similar effects. 44 If properly mitigated, effects on telecommunications, television and radio broadcasting links or scanning telemetry are not a material constraint to wind farm development. 45 Terrestrial television transmitters for domestic reception within the UK are the joint responsibility of the British Broadcasting Corporation (BBC) and Ofcom. Distribution links and other communication links are provided and operated on behalf of the broadcasters Arquiva. 46 Ofcom and BBC have collaborated to create an online wind farm tool which assesses turbine coordinates for their effect on television reception at residential properties in the local area and identifies the transmitters from which signals may be affected. Ofcom and the BBC have used the generally accepted rule that only properties within 500 m of a turbine and those 5 km behind the turbine from the transmitter direction will have the potential to be affected, and tool uses this, and the television licence database, to calculate a number of properties where television reception could be adversely affected. The results of the assessment indicate that 3 homes could potentially be affected as a result of the development, with effects likely on signals received from the Darvel and Black Hill Channel 5 transmitters. 47 Any adverse effects with regard to television and radio interference resulting as a direct effect of the development will be resolved through technical solutions. If potential interference is identified, Vattenfall will assess any Volume 2 of 5 Chapter 19 Aviation, Radar and EMI Page 8 of 9

9 effects and, for any effects caused by the development, will determine the most appropriate technical solution on a case-by-case basis. Solutions include changing the aerial height of the receiver, upgrading the receiving aerial system and / or provision of free to air cable or satellite services. Potential cases of interference will be checked to ensure that the problem is not caused by a damaged aerial, poor aerial alignment, damaged cables or an aerial feeding into too many television sets rather than as a direct result of the wind farm. A suitably worded condition would be an appropriate way to deal with this issue. 48 Effects will be investigated for up to one year after the development becomes operational. Volume 2 of 5 Chapter 19 Aviation, Radar and EMI Page 9 of 9