BAY OF SKAILL SUBSTATION - ORKNEY CAITHNESS CONNECTION

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1 BAY OF SKAILL SUBSTATION - ORKNEY CAITHNESS CONNECTION Helping to secure a Renewable Future: Orkney Caithness Connection Scottish Hydro Electric Transmission Plc Scottish Hydro Electric Transmission Plc (SHE Transmission) is part of SSE Plc and is the transmission licence holder in the north of Scotland. SHE Transmission Plc has a duty, under Section 9 of the Electricity Act 1989, to facilitate competition in the generation and supply of electricity. The company also has obligations to offer non-discriminatory terms for connection to the transmission system, both for new generation and for new sources of electricity demand. Where we are required to extend, upgrade or reinforce our transmission network, we must find an environmentally appropriate, technically feasible and economically viable solution. We believe that our proposals for the Bay of Skaill Substation and Orkney Caithness Connection meet these requirements. Indicative Timeline for Marine Generation Background In March 2010 The Crown Estate announced the leased option areas for the Pentland Firth and Orkney Waters Round 1 Development Sites for marine generation totalling a potential 1600MW. This includes a generation potential of up to 1050MW (wave and tidal) around the Orkney Isles and 550MW off the Caithness coast. The figure above shows the overall potential of the Pentland Firth and Orkney waters combined. The amount of renewable generation that can be exported from Orkney is limited by the capacity of the two existing 33kV subsea cables that connect Orkney to the mainland transmission grid at Thurso. Taking account of the renewable generation that has already been connected or is contracted to be connected on Orkney, the existing subsea connection has now reached full capacity. As a result, new transmission infrastructure is required between Orkney and Caithness. This will need to connect into the existing substation at Dounreay. In addition to upgrades to the existing Dounreay substation a new substation will also be required on the west coast of mainland Orkney to facilitate the connection of the marine generation sites to the network. The proposed Bay of Skaill Substation and Orkney Caithness Connection is being developed to enable the connection of marine renewable energy generation developments off the west coast of Orkney to the National Grid. It is likely that should the development of the tidal and wave renewable generators be successful, then further capacity would be required and allowances have been made for future expansion of the Bay of Skaill Substation site. Summary of Generation Round 1 Development Project Developer Wave/ Tidal Potential Generation Application to connect Costa Head SSE Renewables Developments (UK) Ltd Wave 200MW Brough Head Aquamarine Power Ltd & SSE Renewables Holdings (UK) Ltd Wave 200MW Renewable Energy Infrastructure At present the main driver for the Bay of Skaill Substation and Orkney Caithness Connection is generation off the west coast of Orkney. However there is the potential that further transmission infrastructure will be required dependent on increasing generation. Transmission developments could include the following: a 132kV connection from the proposed substation to the northeastern mainland; a subsea HVDC Link with Orkney and the National Grid by 2020 The purpose of the current SHE Transmission pre-application consultation is for the proposed Bay of Skaill Substation. Although the current substation design has been future proofed to allow for potential future developments it is important to note that SHE Transmission will conduct optioneering studies and consultation on any future transmission development projects on Orkney. Proposed future developments will subject to further consultation and consent applications at that time. Marwick head Scottish Power Renewable UK Ltd Wave 50MW West Orkney Middle South E.ON Climate & Renewables UK Ltd Wave 50MW West Orkney South E.ON Climate & Renewables UK Ltd Wave 50MW Westray South SSE Renewables Developments (UK) Ltd Tidal 200MW Farr Point Pelamis Wave Power Limited Wave 50MW Scottish Hydro Electric Transmission SP Transmission Cantick Head SSE Renewables Holdings (UK) Ltd & OpenHydro Site Development Ltd Tidal 200MW Inner Sound MeyGen Ltd Tidal 400MW Ness of Duncansby Scottish Power Renewable UK Ltd Tidal 100MW National Grid Electricity Transmission Brough Ness Marine Current Turbines Limited Tidal 100MW TOTAL 1.6GW 650MW 1

2 BAY OF SKAILL SUBSTATION ORKNEY CAITHNESS CONNECTION Optioneering Site selection and route selection Substation Site Alternatives The development of this SHE Transmission proposal has involved an optioneering process which included consideration of a number of substation sites, landfall locations, and potential cable route corridors. Individual studies were undertaken for each component part of the project to identify the economic, environmental, and technical implications of the various route and site options as applicable. These were then reviewed together to identify a preferred overall option that optimised these factors across all project components. SHE Transmission consulted on the preferred option in 2011 and following this consultation selected a proposal to conduct more detailed engineering and environmental studies. Orkney Landing Alternatives Cable Route Alternatives Selection of Proposals Bay of Skaill Substation The SHE Transmission Orkney Caithness proposal includes the following: a new 4.2 hectare 220kV Bay of Skaill substation on the west of Mainland Orkney; a 70 km 220kV subsea cable link between Orkney and Dounreay and installation of a 275/220kV transformer and associated equipment at the existing 275kV Dounreay substation. 220kV Subsea Cable Dounreay 275 / 220kV Substation Works Consenting requirements The new Bay of Skaill substation development will be undertaken in accordance with the Town and Country Planning (Scotland) Act 1997 (as amended). A Proposal of Application Notice (PAN) was submitted on March 18th to Orkney Island Council. The submission of the PAN started a 12 week Pre-Application Consultation. SHE Transmission has appointed an Environmental Consultant to undertake an Environmental Impact Assessment for the proposed substation development. The installation and operation of the subsea cable requires a Marine License from Marine Scotland under the Marine (Scotland) Act 2010 and the Marine and Coastal Access Act A voluntary Environmental Appraisal has been prepared to accompany this application. Underground electricity cable works will be carried out under the provision for permitted development under Class 40 of the Town and Country Planning (General Permitted Development) (Scotland) Order 1992 (as amended). 2

3 BAY OF SKAILL SUBSTATION - ORKNEY CAITHNESS CONNECTION Bay of Skaill - Substation Site Proposed Bay of Skaill substation site location The proposed Bay of Skaill Substation site is located in a coastal position southwest of Vestra Fiold, west of Quoyloo and north of Northdyke. The substation is required in order to enable marine developments to connect to the transmission network. As the substation will be in close proximity to the coast there is a requirement to protect the equipment from possible corrosion caused by salt in the sea air. This protection is provided by placing the substations equipment within buildings. The buildings will be generally be of similar appearance to large agricultural sheds, based on a steel portal frame with industrial cladding on the exterior. Gas Insulated Switchgear (GIS) is proposed for the Substation. GIS is smaller than the traditional Air Insulated Switchgear (AIS) design. The footprint of the platform and land cut is approximately 4.2 hectares. The platform for the substation will be cut into the land at the site so as to provide a flat site and also reducing the overall height of the development on the landscape, reducing the visual impact. Landscaped earth bunds may be used to screen ground level activities. The site will be surrounded by a 2.4m high security fence of palisade construction and be fitted with a CCTV system. Illumination will be provided internally to allow safe working during construction with limited lighting at access points to allow safe access to the compound and building. Potential Construction programme Subject to consent, Ofgem funding approval and the expected development of marine renewables, construction may start in the spring of Construction typically involves the following: It usually takes about 2 years to build this type of substation. Initial civil works including preparation of the access road and earthworks are conducted during the first 6 months. Following civil works buildings are constructed and electrical equipment is installed, involving the delivery of abnormal loads i.e. the two transformers with each weighing up to 170 tonnes. Commissioning and connection of electrical equipment followed by final landscaping. It is anticipated that the subsea cable would be installed during the summer of 2017 with the 220kV connection commissioned in the Spring of

4 BAY OF SKAILL SUBSTATION ORKNEY CAITHNESS CONNECTION Current Views of the Existing Bay of Skaill Substation Site Proposed Bay of Skaill Substation Planning Application Buildings 220/132kV Transformer Building 132kV GIS, Control Room, and Welfare 132/33kV Transformer Buildings (x2) Indicative View of Proposed Bay of Skaill Substation Future HVDC Consideration 4

5 BAY OF SKAILL SUBSTATION - ORKNEY CAITHNESS CONNECTION EIA baseline studies for the proposed Substation Site The following environmental baselines studies have been conducted at the site: Extended Phase 1 Habitat Survey (including Otter survey) - June 2011 Phase 1 Habitat - Verification walkover - August 2012 Breeding Bird Surveys - May and June 2012 Wintering Bird Surveys - December 2012 to March 2013 Geophysical (gradiometer) survey - April and May 2012 Archaeology Watching Brief (monitoring of 26 geotechnical trial pits and two trenches) - September 2012 Cultural heritage assessment A non-intrusive geophysical survey of the substation site has been undertaken to help assess archaeological interests. The site was found to be of generally low archaeological interest. Intrusive site investigations were then undertaken on the substation and landfall locations to assist in the design progression. The assessment has not identified anything which would require preservation in situ. Based on the current assessment no further work is recommended prior to development. SHE Transmission will ensure that emergency procedures are in place in the event that unidentified archaeology is identified during construction work. Construction Environmental Management A project Construction Environmental Management Document (CEMD) will be prepared and will include all mitigation measures and environmental commitments proposed in the Environmental Impact Assessment and will be updated with any relevant conditions of the planning consent as necessary. SHE Transmission will ensure that the CEMD is included as part of the contract for construction of the Substation. SHE Transmission will be responsible for ensuring that all work is conducted in accordance with the CEMD. Orkney Caithness Connection Programme The current programme for the project is shown below: Develop and compare substation sites / route options Complete Identify preferred substation site Complete Undertake public exhibition for preferred substation sites Complete Submit Proposal of Application Notice for substation site Complete Complete Subsea Cable Marine Environmental Appraisal Complete Submit Marine Scotland consent application for cable April 2013 Complete Substation Environmental Impact Assessment May 2013 Submission of Planning Application June 2013 Start Orkney Substation Construction May 2015 Start Subsea Cable Works Jan 2017 Phased Completion and Commissioning Nature conservation assessment Phase 1 Habitat surveys have indicated that 75 % of the site consists of improved / semi-improved grassland with the remaining 25 % unmodified coastal grassland. No European Protected Species have been identified at the site. The following bird species have been recorded at the site: Arctic Tern; Skylark; and Common Gulls Nature conservation mitigation will be detailed in the Environmental Statement and be included in the CEMD. Pre-construction surveys will be carried out 5

6 BAY OF SKAILL SUBSTATION - ORKNEY CAITHNESS CONNECTION Potential photomontage view points Zone of theoretical visibility As part of the environmental impact assessment for the proposed Bay of Skaill substation a landscape and visual impact assessment will be conducted. SHE Transmission would like feedback from the local community and key consultees on view points that may require more detailed assessment. For selected viewpoints photomontages will be produced. Photomontages are prepared by landsape and visual specialists and are created to show how the development will look once built. As part of the landscape and visual impact assessment a zone of theoretical visibility (ZTV) is created with 3D modelling software. The ZTV for the Bay of Skaill Substation indicates that the development will be visible from the ocean but that visibility is limited to the east. Substation Visualisation - Indicative colour options Light Green Dark Green Grey Brown Landscape and Visual Mitigation Proposals SHE Transmission landscape and visual mitigation has included the following: a site selection process sensitive placement of earthworks use of GIS versus AIS equipment enclosed equipment in sensitively coloured buildings dry stone walls as appropriate The above indicative visualisations show the substation development finished in various indicative colours. Indicative placement of excess earthwork material is also shown, which can be used to help screen the development from visual receptors. SHE Transmission would like comments from the local community and consultees on the proposed landscape and visual mitigations i.e. preferred colour for the substation and where excess material is best placed for screening of the site. Feedback This exhibition is an opportunity to comment on and ask questions about the current proposals. We would greatly appreciate it if you would take the time to fill out our short questionnaire and post it in the comments box. Alternatively, you can write to: Lisa Marchi Scottish Hydro Electric Transmission Plc 10 Henderson Road Inverness IV1 1SN Please submit your comments on our proposals by Monday 27th May During the determination of the Planning Application you also have the right to express your opinions on the development to Orkney Islands Council. We have set up a webpage for this project, which will be updated with this presentation material. The web page can be found at: 6

7 ORKNEY CAITHNESS CONNECTION Preferred Cable Route Development The subsea cable route between Orkney and Caithness was developed from the preferred option presented during the 2011 presentations. Subsea Survey Subsea survey specifications 560m Corridor surveyed Survey covered preferred and alternative landfall options at each end Total length of survey, including alternate landfall, approximately 81km Geophysical, Geotechnical and Environmental Surveys 2 vessels utilised (on-shore and off shore) Marine Mammal Observer present during geophysical surveys Summary subsea survey findings Water Depth along route to <100m Sediments varied significantly, from fine sand to diamicton with gravel, cobbles and boulder. Within offshore sand, several areas of mega-ripples were recorded with wavelengths of up to 10-12m and heights of m Bedrock recorded at both landfalls, extending to approximately 200m from coastlines. No contaminants identified No Priority Marine Features identified Profile of sea depth with distance along survey from Caithness Excerpt from subsea survey report showing environmental sample locations, bed type and habitat types. Environmental Sample Collection Subsea Cable Design Final route length 70 km One cable crossing (FARICE-1) Route crosses through Brough Head Wave Farm Development Site Developed to maximise chance of burial (avoiding diamicton where possible) The cable will be buried to a depth of m, where possible, using a cable plough or water jetting trencher Rock placement cable protection will be required where sufficient burial depth cannot be achieved. HDD landings proposed at both ends of cable The cable is anticipated to be approximately 400 mm 2 at 220kV with a diameter of 250 mm and weight of approximately 100 kg/m Typical 3 core cable Cable plough Water Jetting trencher design During the subsea survey Environmental samples were collected, as well as photos and video of transects of the sea bed undertaken. The plate shown above is an example of an Environmental Sample collected and analysed during the subsea survey. The photos below show some of the equipment used to collect these samples during the survey. 7