12 June 2012 40Mw Lewis Wave Array
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ENVIRONMENT AND PROTECTIVE SERVICES COMMITTEE: 12 JUNE 2012 40MW LEWIS WAVE ARRAY (REF NO 12/00169/CONSG) Report by Director of Development PURPOSE OF REPORT To determine the Comhairle’s view as a ‘statutory consultee’ in respect of an Environmental Statement (ES) submitted in March 2012 to the Scottish Ministers regarding plans to construct and operate a Wave Energy Convertor Array located off shore in Northwest Lewis, (an application for consent under Section 36 of the 1989 Electricity Act). The application also seeks a marine licence under part 4, Section 36 of the Marine (Scotland) Act 2010. COMPETENCE 1.1 There are no legal, financial or other constraints to the recommendations being implemented. SUMMARY 2.1 The Scottish Ministers have asked for the view of the Comhairle on a proposed Wave Array off the coast at Siader, North West Lewis. The application submitted to Scottish Ministers, on behalf of Lewis Wave Power Limited (LWP), comprises between 40 and 50 oyster devices with an installed capacity of 40 MW. An Environmental Statement (ES) has been prepared by LWP. The Comhairle has until 21 July 2012 to submit comments on this ES and the proposed development. The Report summarises the ES; includes consultees’ comments received on the ES; it offers a conclusion and a recommended favourable view to be submitted to Scottish Ministers. Copies of the Non-Technical Summary of the ES will be made available in the Members’ lounge prior to the meeting of the Environment and Protective Services Committee on 12 June 2012. 2.2 The Report relates to the marine element (below high water mark) only of the proposal. A separate planning application will be submitted to the Comhairle for the determination of the onshore works. RECOMMENDATIONS 3.1 It is recommended the Comhairle agrees that the: a) View at paragraph 15.8 of the Report be submitted to the Scottish Ministers; b) Comhairle inform Scottish Ministers that there is no public interest in holding a Public Local Inquiry for the Lewis Wave Array application. Contact Officer Hannah Morrison Telephone 01870 604990 Email: [email protected] Appendices 1 Indicative Site Layout (Vol 2 ES Ch5 Fig 5.2 ) 2 Diagram showing how the Oyster WECs relate to the hydro electric power station ( Vol 2 ES Ch5 Fig 5.3) 3 Illustrations of the Oyster WECs (Vol 2 ES Ch5 Fig 5.4) 4 Plan of target scenario for WEC positioning in relation to nearest WEC (Vol 2 Ch5 ES Fig 5.5) 5 Indicative Illustration of the array layout (Vol 2 ES Ch5 Fig 5.6) 6 Illustration of rock or stabilization anchor (Vol 2 ES Ch5 Fig 5.8) 7 Oyster Technical Specifications (Vol 2 ES Ch5 Table 5.1) 8 Combined ZTV for Offshore & Onshore Development (Vol 3 Technical Appendices Fig 14.5) 9 Cumulative Zone of Theoretical Visibility [ZTV] (Vol 3 Technical Appendices Fig 14.13) 10 SEPA Response 11 Historic Scotland Response 12 Marine and Coastguard Agency Response 13 RSPB Response and Annex 14 Whale and Dolphin Conservation Society Response 15 Archaeology Comments 16 Economic Development Comments BACKGROUND 4.1 In March 2012, Lewis Wave Power Limited (LWP) submitted an application for consent under Section 36 of the 1989 Electricity Act. The application also seeks a Marine Licence under part 4, Section 36 of the Marine (Scotland) Act 2010 in addition a decommissioning programme agreed with the Department of Energy and Climate Change and Marine Scotland - Licensing and Operations Team will be developed pursuant to Chapter 3 of the Energy Act 2004 for the 40MW Lewis Wave Array. 4.2 Lewis Wave Power, a wholly owned subsidiary of Edinburgh based Aquamarine Power Limited, proposes to install between 40 and 50 Oyster Wave Energy Convertors off the coast of North West Lewis in an area leased from The Crown Estate. Although this application only relates to the offshore element of this project, an agreement has been made with the Galson Estate Trust to construct, operate and maintain the proposed wave farm on land under their ownership. 4.3 The Report relates to the development of the proposed Lewis Wave Array which is located in inshore waters off the northwest coast of Lewis at Lower Siader. The Report relates purely to the elements of the development that lie below the high water mark. 4.4 The Oyster device is a buoyant, hinged flap attached to the seabed by monopole in depths of 10m to 15m. As waves pass, the flap pitches backwards and forwards, driving two hydraulic pistons which pump water at high pressure to a conventional onshore Hydro- electric turbine generator. 4.5 The development proposes the installation, 20 year operation and subsequent decommissioning, of 40 to 50 Oyster devices. Details of the devices are shown at Appendix 3 to the Report. 4.6 The entire development site encloses an area comprising 257ha. The proposed location and layout of the Wave Farm are shown on the Site Plan at Appendix 1; and the indicative Site Layout at Appendix 5 to the Report. 4.7 Accompanying the current application, LWP have included an Environmental Statement which is comprised of 3 parts: • Non-technical Summary: Volume 1 • Environmental Statement: Volume 2 • Appendices: Volume 3 4.8 In order to properly consider all relevant matters the Report is structured as follows: Section 4 Background; Section 5 Description of the Project; Section 6 Summary of Environmental Statement; Section 7 External Consultation Responses; Section 8 Internal Consultation Responses; Section 9 Representations; Section 10 Comments from Applicant Section 11 Policy Context; Section 12 Discussion of Proposals; Section 13 Issues Raised; Section 14 Policy Consideration; Section 15 Conclusion and Recommended view. DESCRIPTION OF THE PROJECT 5.1 Lewis Wave Power proposes to develop a wave energy array off the north-west coast of the Isle of Lewis. The array will have a generation capacity of up to 40MW of renewable power for export to the national grid. 5.2 The array will consist of between 40 and 50 Oyster wave energy convertors (WECs) also referred to as Oyster devices, depending on the design and therefore final power rating of the Oyster devices used. These devices will be positioned according to the best understanding of available wave resource, water depth, seabed gradient and seabed protrusions. 5.3 The Oyster array will be located in waters to the north of Siadar and to the west of Bhuirgh (see Appendix 1 Fig 5.2 Location Plan to the Report). The wave array will be configured in a linear formation running roughly parallel to the coast and will cover a distance of up to 3.2km from end to end and extends a maximum distance of 0.9km from the shore. Indicative locations for the individual devices are displayed in Appendix 1 Fig 5.2. These will be subject to micro-siting and the layout is indicative. 5.4 Depending on the option chosen for installation, the total area of seabed directly affected would be a minimum footprint of 46,520m2 (4.6ha) to a maximum footprint of 259,656m2 (26ha) which encloses a maximum site boundary of 257ha. 5.5 In addition to the Oyster devices there will be a requirement for supporting infrastructure both onshore and offshore. This will include pipe work which will connect the devices to a hydro- electric power station, located onshore, within an area of land to the north of Siadar village, please note this information is provided for context, but this application is solely related to the offshore aspects of the development below the high water mark. 5.6 The system is designed so that the off-shore components are as simple and as reliable as possible. The operation of the off-shore part of the project will not rely on any electrical components or active control functions operating in the marine environment. Once all four phases of the development have been installed and are operational the nominal peak output of the entire array will be approximately 40MW with a predicted average output of approximately 11.3MW. During periods of low wave action the output of the array may fall to 0MW. Site Description 5.7 The waters off the north-west coast of Lewis are shallow and, while the seabed slopes gently down towards the continental shelf, the waters remain no deeper than 50m out to a distance of 4 to 5km from the coastline. The near shore environment is generally rocky with some areas of coarse sand and gravel in pockets between rock outcrops and boulders. With greater distance offshore the seabed becomes more stable and is composed of finer sands and gravels. 5.8 The bathymetry within the development site ranges between 10m and 15m depth, the depth range required by the Oyster Wave Energy Convertors (WECS). The seabed is reasonably level with few discernable anomalies. 5.9 The west coast of Lewis is a location with abundant wave energy, Atlantic swells arrive at the coast having been uninterrupted by any land mass for thousands of miles. 5.10 Wave Energy Convertors (WECs) Waves have the potential to provide a sustainable source of energy which can be captured and converted into electricity by WECs. Aquamarine Power Limited’s Oyster WEC technology is designed to harvest the wave energy from the near shore environment. 5.11 The power rating for each Oyster WEC which will be deployed at the Lewis site will be between 800kW and 1MW. This will determine the number of Oysters deployed in the array: 40 will be required if the power rating is 1MW; up to 50 if the rating is 800kW.