Overcoming Ecological Challenges and Exploring Biodiversity Opportunities Associated with Energy Infrastructure Projects in Scotland

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1 Overcoming Ecological Challenges and Exploring Biodiversity Opportunities Associated with Energy Infrastructure Projects in Scotland Kathy Dale EnviroCentre Limited

2 Summary Scotland s renewables targets and its energy infrastructure needs Consenting requirements, infrastructure types and construction methods Application of energy infrastructure guidance Route selection and infrastructure design Case studies and key principles

3 Needs some statistics The total electricity generation in Scotland per year is about 50TWh. About 38% of electricity generated in Scotland is classified as renewable. Of the renewables, wind is 62% and hydro 29%. Consumption of electricity in Scotland is about 40TWh (excl. heating and transport). The excess generation is exported, almost all to England but some goes to Ireland. The current capacity of wind farms in Scotland is about 7.5GW. The total planned capacity is 20.8GW, i.e. an increase of 2.8x. The on-shore wind capacity will increase from 7.5GW to 16GW, i.e. just over 2x. By 2020 the total amount of renewable electricity generated in Scotland will be roughly equal to the amount consumed the 100% target. In Scotland there are regular constraint payments to wind farms to stop them generating when there is either no demand or the interconnectors have insufficient capacity to take the electricity to where it might be needed. There are no statistics easily available on the length of the grid connections either existing or in planning.

4 Smart Grid Support a grid network fit for the future: We need a smart grid that accommodates high levels of renewable energy

5 Consenting Requirements Section 37 of the Electricity Act 1989 (UK) Section 57 of the Town & Country Planning (Scotland) Act 1997 as amended by The Planning Etc. (Scotland) Act 2006 Town and Country Planning (General Permitted Development) (Scotland) Order 1992 (as amended)

6 Environmental Impact Assessment Overhead lines, underground cables and ancillary works: EIA development by virtue of voltage and/or length Electricity Works (Environmental Impact Assessment) (Scotland) Regulations 2000 (as amended) Non-EIA development will require an Environmental Report

7 Land Rights Access permission required for survey Wayleaves, servitudes and easements required Voluntary OR application to Department of Planning and Environmental Appeals, with final decision coming from Minister Land acquired either by voluntary or compulsory purchase Land also required for access routes, temporary set-down areas and other construction activities Mitigation and compensation proposals may require landowner co-operation

8 Infrastructure Types Towers (>132kV) Span lengths between 250m and 350m but up to 400m Average height for 132kV between 20m and 30m; average height for 275kV and 400kV between 41m and 46m Wood poles (132kV) Span lengths between 80m and 100m but up to 120m Average height between 14m and 16m Underground cables Require a working corridor of 30m

9 Construction Methods Overhead lines Accesses and laydown areas established Vegetation clearance Tower foundations 2 weeks Tower construction 1-2 weeks Conductor erection and stringing up to 4 weeks Periods spread over 4 months Wood pole lines shorter periods Underground cables Open cut trenching 160m/week Mole ploughing Directional drilling Cable jointing pits

10 SPEN Guidance (May 2015) Applies to major electrical infrastructure projects which are defined as developments of overhead lines, underground cables and substations at 132kV and above Relevant to Scotland, England and Wales Wherever practical, an overhead line approach is taken but there are specific circumstances in which an underground approach is considered

11 SPEN Approach Premise Overhead line - major effects are visual Underground cable major effects are ecological and archaeological Approach Stage 1 Appraisal of route options including stakeholder engagement (not prescriptive in Scotland) Stage 2 EIA of preferred route including consultation

12 SPEN Approach

13 Stage 1 The Routeing Process Objective - to identify a technically feasible and economically viable overhead line route, between specified points, which causes the least disturbance to people and the environment. Iterative approach - the steps may be re-visited several times. The outcome of each step is subject to a technical and, where relevant, consultation, check with key stakeholders and the public, prior to commencing the next step. Professional judgement is used to establish explicitly the balance between technical, economic and environmental factors.

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15 Design - The Holford Rules Developed in 1959 by Lord Holford Reviewed circa 1992 by the National Grid Company (NGC) Plc Subsequently reviewed by Scottish Hydro Electric Transmission Limited (SHETL) in 2003 to reflect Scottish circumstances Primarily devised to protect landscape and amenity The term amenity value in the Rules is often interpreted now as environmental value to reflect wider intrinsic value

16 Design - Other Guidelines Forestry Commission Guidelines Overhead lines should be routed to follow open space and to run alongside, not through, woodland Where there is no alternative route, guidelines are provided for an overhead line through a forested area (visual) Horlock Rules Devised in 2003 and updated in 2006 Provide guidelines for the siting and design of new substations, or substation extensions, to avoid or reduce environmental effects

17 Ecological Routeing Considerations Avoidance of features Minimisation of impacts Access to the route Likely success of micro-siting and reinstatement Seasonal constraints Opportunities for enhancement

18 Stage 2 EIA or Ecological Report Review of likely significant adverse effects Triggers for undergrounding? Scoping Detailed survey work Consultation Impact assessment Description of alternatives covered by route selection process Mitigation measures Ecological enhancement

19 Protection of Important Ecological Features Use peat depth maps to avoid deep peat where possible Minimise footprint of towers/poles Carefully design access routes Use of temporary floating tracks to access across sensitive botanical habitats Use spans or directional drilling to cross sensitive habitats Micro-site to minimise tree loss/damage Timing of works for protected species Use of Ecological Clerk of Works

20 Impacts on Birds Birds most prone to collision: Less agile, large-bodied species with proportionally small wingspans Birds that congregate in large numbers during migration Collisions take place most often at specific highrisk locations and often at night Electrocution is primarily associated with the lowand medium-voltage power lines (distribution network)

21 Bird Mitigation Avoidance of multi-level vertical arrangements and general lowering of the lines Fitting of rejectors and insulation Use of markers to increase visibility Removal of the earth wire Impact monitoring and evaluation of mitigation effectiveness (bird strike indicators and carcass collection)

22 Alternative Pole Designs A a safe horizontal low voltage line, with three conductors suspended below the cross-arm with sufficiently long insulators A B a low voltage line unsafe for larger waders and larger raptors because of conductors attached on short insulators on top of the cross-arm - in this case retrofitting could include insulating the central conductor wire and/or covering the insulators B

23 Maximising Ecological Opportunities Gathering data and sharing it Replacement poles with improved design Habitat management plans Habitat creation through screening proposals Opening up of forest wayleaves (in some locations) Access improved to mitigate for previous impacts Compensation boosted to provide enhancement Re-alignment of lines and amalgamation to reduce hazards to birds

24 Maximising Ecological Opportunities Habitat creation through screening proposals

25 Case Study 1 Glen Lyon Longest glen in Scotland Road and river along bottom of glen Limited access to south side of river National Scenic Area River Tay SAC Glen Lyon Woods SSSI AWI sites Atlantic salmon Otter Lamprey species Freshwater pearl mussel Bats Badgers 7 hydro schemes 16 watercourse crossings 4 crossings of River Lyon 1 bridge crossing 1 OHL crossing 2 directional drill crossings Majority mole ploughed Some open cut

26 Case Study 1 Glen Lyon Ecological survey of whole route and all watercourses Appropriate Assessment (no EcIA) Watercourse crossing schedule Otter licences Timing of river works Restricted use of fords agreed with SEPA ECoW supervision Minimal habitat reinstatement required due to mole ploughing Bat box installation Bridge built to access south side of river in future

27 Case Study 2 Central Scotland SPEN Guidance - Stage 1 Desk study Site walkover difficulties with access Constraints map Bird surveys started 14 route options proposed Ecological risk assessment of options

28 Case Study 2 Central Scotland Main issues: SPA, SSSIs, AWI sites Acid grassland/mire Watercourses Breeding waders, wintering wildfowl, Black Grouse Protected species Other OHLs in the study area Risk Assessment of Options: High - potentially significant effects Medium - potential for some effect but mitigation opportunities Low - no obvious constraints Through avoidance, no high risk options have been identified

29 Case Study 2 Central Scotland Next steps: Preferred route to be identified Consultation document Consultation Proposed route identification Scoping document Consultation EIA Planning submission Whole process likely to take 18 months to 2 years

30 Key Principles Smarter distribution networks needed, including increased interconnection with other nations so demand matches supply Landowner consultation and co-operation is crucial If the major effects are visual for an overhead line and ecological and archaeological for an underground cable, then an iterative approach to route optioneering is vital The balance between technical, economic and environmental factors must be explicit Protection of important ecological features requires standard and novel approaches and design can be critical Take all opportunities to maximise ecological enhancement some schemes can have long term benefits with smarter thinking Promote partnership working and use an ECoW to help make pragmatic decisions, especially in remote areas

31 Thanks for listening