Fort Augustus– Skye Project Consultation September 2016
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Fort Augustus– Skye Project Consultation September 2016 Scottish and Southern Electricity Networks Who we are Our licence stipulates that we must develop and maintain an efficient, co-ordinated and economical system of electricity transmission. What is the difference between Transmission and Distribution? Other SSE Electricity Transmission is the transportation of Businesses electricity from generating plants to where it is required at centres of demand. Scottish Scottish Hydro Southern The Electricity Transmission network, or grid, Hydro Electric Electric Power Electric Power transports electricity at very high voltages through Transmission Plc Distribution Plc Distribution overhead wires, underground cables and subsea (SHE Transmission) (SHEPD) (SEPD) cables. The transmission network connects large scale generation, primarily renewables, to central and southern Scotland and the rest of Great Britain. We are part of Scottish and Southern The Electricity Distribution network is connected into Electricity Networks, operating under the Transmission network but the voltage is lowered by transformers at electricity substations, and the power licence as Scottish Hydro Electric is then distributed to homes and businesses through Transmission Plc for the transmission overheadOverview lines or underground of cables. of electricity in the north of Scotland. OverviewTransmission of Transmission projects projects Shetland In total we maintain about 5,000km of overhead lines and underground cables – easily enough to stretch Overview of ExistingExisting infrastructure across the Atlantic from John O’Groats all the way Transmission projects Shetland Completed to Boston in the USA. Completed UnderUnderExisting construction infrastructure Orkney Completed PotentialPotentialUnder construction development Orkney developmentPotential development Our network crosses some of the UK’s most challenging AdvancedAdvanced planning planning Advanced planning terrain – including circuits that are buried under the Gills Bay seabed, are located over 750m above sea level and Dounreay Spittal Mybster up to 250km long. Gills Bay Dounreay Lairg Western Isles Loch Buidhe Spittal The landscape and environment that contribute (Bonar Bridge) to the challenges we face also give the area a rich Mossford Moray Firth Mybster Blackhillock Beauly Knocknagael resource for renewable energy generation. There is a Skye Peterhead Kintore high demand to connect from new wind, hydro and Tomatin Fort Augustus LairgAberdeen marine generators which rely on Scottish and Southern Western Isles Loch Buidhe Electricity Networks to provide a physical link between Fort William (Bonar Bridge) the new sources of power and electricity users. Scottish Dalmally Mossford Moray Firth and Southern Electricity Networks is delivering a major Perth programme of investment to ensure that the network is Kincardine Blackhillock Denny Beauly Knocknagael ready to meet the needs of our customers in the future. Skye Peterhead Kintyre Hunterston Arran Our responsibilities Tomatin Kintore Fort Augustus Aberdeen As we are the only company that owns an electricity transmission network in the north of Scotland we are closely regulated by the energy regulator Ofgem. We are Fort William issued with a licence to operate and we must adhere to the terms of the licence. For this reason we operate on a very separate basis to other SSE businesses. Dalmally Perth Kincardine Denny Kintyre Hunterston Arran Fort Augustus– Skye Project Project Overview We are in the early stages of developing a project which will provide an increase of electrical capacity for the Isle of Skye. An additional 132kV overhead line to Skye is required to enable the connection of new generation located in the north of the island. This will also improve the resilience of the transmission network between Fort Augustus and Skye. The main elements of the project are as follows: • Construction of an additional, new 132kV overhead • Installation of additional equipment and minor line using a double trident H wood pole from the works at the existing Edinbane substation; and existing Fort Augustus substation to the existing • Dismantle and remove the existing 132kV overhead Broadford substation; a small section above 400m line connecting Broadford and Edinbane substations. may require a steel support arrangement. • Construction of a replacement, higher capacity, Whilst we are still at an early stage of the project 132kV overhead line using a double trident H wood development we do not anticipate any physical pole between the existing Broadford substation and expansion of the Broadford and Edinbane substations the existing Edinbane substation; nor any new or additional equipment being installed • Installation of additional equipment and minor within the existing site boundary. The project will works on the 33kV network at the existing connect into existing infrastructure at the Broadford substation; Fort Augustus substation. Route Corridor Preferred Route Option (approximately 1km wide) Existing Route Project Timeline The chart below shows the main stages of the development process and the opportunities where members of the public can provide comments or feedback in regards to proposals. Please note that all dates are indicative at this stage. Early 2016 Initial consultation and options assessment Consultations with key statutory bodies such as Scottish National Heritage, The Highland Council, Historic Environment Scotland and Scottish Environment Protection Agency have been undertaken to seek feedback on the project and assessment methodologies. Engineering and high level environmental studies have also been carried out on the technology / corridor options. Spring 2016 Technology confirmed and route selection study started Proposed technology and overhead line corridor (wide area between connection points) identified and further environmental studies undertaken within the defined corridor. Route options identified, options appraisal undertaken and preferred route identified. September 2016 Public consultation Consultation with statutory, non-statutory bodies and communities on initial project proposals. Document detailing scope of consultation published. Autumn 2016 – Further environmental studies, initial overhead line Summer 2017 design and alignment selection progressed Review all feedback and publish the Report on Consultation. Confirm the proposed route.Undertake further environmental studies and initial engineering design to identify the preferred alignment for the overhead line. Confirm the preferred alignment for the overhead line. Summer 2017 – Consultation on preferred alignment selection Late 2017 Undertake consultation on the preferred alignment for the overhead line and hold further public consultations. Late 2017 – Consent application & contract tendering Early 2019 Confirm the proposed overhead line alignment and publish the Report on Consultation. Progress Environmental Impact Assessment (EIA), negotiations with landowners, preparation and submission of Section 37 consent application, contract tendering and procurement detailed design. Early 2020 – Construction and commissioning Late 2022 Technical Options Assessment Existing Infrastructure The existing 132kV overhead line which connects Fort Augustus and Skye consists of three distinct sections, which were constructed at different times over the past 65 years in response to changing needs. These include: • Fort Augustus Substation – Skye Tee – Quoich – steel lattice towers designed to carry a single circuit (three conductors) • Quoich to Broadford – steel lattice towers designed to carry two circuits, presently strung with a single circuit • Broadford to Dunvegan – trident wood pole designed to carry a single circuit Assessed Options A number of different technical solutions have been considered in the early design stages including the construction of a new connection or upgrading and using existing infrastructure. These options have been compared in order to understand the most balanced solution whilst considering technical, economic, environmental and consenting factors. The following table provides a summary of this comparison and highlights our proposed technical solution to achieve the increase in capacity between Fort Augustus and Skye. Trident 'H' Wood Pole proposed technology. Technology options appraisal Technical – safety, access & Environmental/Consenting Economic – Operational – ease of construction, security – Land use, landscape & Capital & Ease of maintenance, of supply, meets generator visual, protected species operational safety, restoration Serial Technology Type connection requirements and habitats costs of supply 1 Single circuit wood pole (H configuration) 2 Double circuit steel lattice tower 3 Single circuit wood pole (H configuration) but utilising the existing assets where possible 4 AC subsea cable and single circuit wood pole (H configuration). 5 HVDC Subsea cable and single circuit wood pole (H configuration) 6 Reconductor the existing circuit with a higher capacity conductor 7 New technology – composite poles & high temperature conductors (HTCs) 8 Cable a new circuit using using HVDC technology 9 Cable a new circuit using AC technology Most preferred Least preferred Routeing Process and Considerations Our overhead line projects are The routeing process is carried out in stages which look progressively in more detail at where the overhead subject to a detailed routeing process. line will be sited, from a wide area (corridor), to a This ensures the final