1. Non-Technical Summary
- Berwick Bank Wind Farm Limited (BBWFL) is a wholly owned subsidiary of SSE Renewables Limited and will hereafter be referred to as ‘the Applicant’. The Applicant is developing the Berwick Bank Wind Farm (hereafter referred to as ‘the Project’).
- The Project is a proposed offshore wind farm located in the outer Firth of Forth and Firth of Tay, approximately 37.8 km east of the Scottish Borders coastline (St. Abb’s Head) and 47.6 km to the East Lothian coastline (see Figure 1.1 Open ▸ ). The Project is comprised of both the offshore and onshore infrastructure required to generate and transmit electricity from the offshore wind farm to a Scottish Power Energy Networks (SPEN) 400 kV Grid Substation located at Branxton, south west of Torness Power station. The offshore export cables will make landfall at Skateraw on the East Lothian coast.
- The offshore components of the Project (hereafter referred to as the ‘Proposed Development’) include the offshore wind farm (the wind turbines, their foundations and associated inter-array cabling), together with associated transmission infrastructure including Offshore Substation Platforms (OSPs)/Offshore convertor station platforms, their foundations, interconnector cables, offshore export cables and cable protection. A separate application will be submitted to the East Lothian Council (ELC) for the onshore elements of the Project.
1.1.2. Purpose of this Document
- This document is a Non-Technical Summary (NTS) of the Environmental Impact Assessment (EIA) Report prepared for the Proposed Development. The Offshore EIA Report provides the environmental information which has been gathered in order to carry out an assessment of the likely significant environmental effects of the Proposed Development.
- This NTS is intended to act as a stand-alone document that will provide an overview of the environmental effects of the Proposed Development in non-technical language. For more detailed information, the full Offshore EIA Report should be referred to (see volumes 1 to 4 of the Offshore EIA Report).
- The Offshore EIA Report provides a description of the Proposed Development and presents the environmental information which has been gathered in order to carry out an assessment of the likely significant environmental effects of the Proposed Development (seaward of Mean High Water Springs (MHWS)) on the receiving environment.
- The Offshore EIA Report specifically:
- provides statutory and non-statutory consultees with technical information to facilitate understanding of the Proposed Development;
- presents the existing environmental baseline information, established from desktop studies, site-specific surveys and/or consultation;
- describes the EIA methodology used for the assessments;
- presents the potential environmental impacts arising from the Proposed Development, based on baseline information and data gathered, and the analysis and assessment of likely significant effects, including consideration of cumulative, inter-related and transboundary effects, completed as part of the EIA process;
- outlines any limitations encountered during the compilation of the environmental information, including where any data gaps or deficiencies exists, and the level of confidence in the information gathered;
- identifies designed in measures to avoid, prevent, reduce or, where possible, offset any identified significant adverse effects on the environment, and where appropriate, proposed monitoring arrangements to validate findings of the Offshore EIA Report. Where additional mitigation measures have been identified, the residual significance of effect has also been presented; and
- provides a description of the reasonable alternatives considered for the Proposed Development, and an indication of the main reasons for site-selection.
- The Offshore EIA Report is divided into four volumes:
- volume 1 – Introductory Chapters;
- volume 2 – Offshore EIA Report Technical Assessments;
- volume 3 – Offshore EIA Technical Reports; and
- volume 4 – Outline Management Plans.
- Based on the Scoping Opinions received and discussions with stakeholders, this Offshore EIA Report focuses on the following topic areas:
- Physical Processes;
- Subsea Noise;
- Benthic Subtidal and Intertidal Ecology;
- Fish and Shellfish Ecology;
- Marine Mammals;
- Offshore and Intertidal Ornithology;
- Commercial Fisheries;
- Shipping and Navigation;
- Aviation, Military and Communications;
- Seascape, Landscape, Visual Resources;
- Cultural Heritage;
- Infrastructure and Other Users;
- Offshore Socio-Economics and Tourism;
- Water Quality; and
- Major Accidents and Natural Disasters.
- Based on the Scoping Opinions received and discussions with stakeholders the following topic areas were scoped out of the assessment:
- Traffic and Transport;
- Air Quality;
- Airborne Noise; and
- Marine Archaeology.
- Marine archaeology was scoped out of this assessment; however, a Written Scheme of Investigation (WSI) and a Protocol for Archaeological Discovery (PAD) are included in volume 4, appendix 22.
- Throughout the offshore EIA process, the Applicant has undertaken extensive consultation with statutory and non-statutory stakeholders, and actively engaged with the public at Public Consultation Events. Details of the consultation with statutory and non-statutory stakeholders and public consultation events is presented in volume 1, chapter 5, together with a full list of stakeholders who were consulted. Topic specific consultation is also provided in each topic chapter (see volume 2, chapters 7 to 21). A summary of the consultation is presented in section 1.5.
1.1.4. The Applicant
- The Applicant is a wholly owned subsidiary of SSE Renewables Limited. SSE Renewables Limited is a leading developer, owner and operator of renewable energy across the United Kingdom (UK) and Ireland, with a portfolio of around 4 GW of onshore wind, offshore wind and hydro. Part of the FTSE-listed SSE plc, its strategy is to drive the transition to a net zero future through the world class development, construction and operation of renewable energy assets.
- SSE Renewables Limited is currently constructing one of the world’s largest offshore wind energy project, the 3.6 GW Dogger Bank Wind Farm in the North Sea, which is a joint venture with Equinor and Eni, as well as Scotland’s largest and the world's deepest fixed bottom offshore site, the 1.1 GW Seagreen Offshore Wind Farm in the Firth of Forth, a joint venture with Total Energies.
- When complete, Dogger Bank and Seagreen will help power millions of UK homes and businesses and drive the transition to Net Zero carbon emissions. These assets will join SSE Renewables Limited’s existing operational offshore wind portfolio which consists of 487 MW across two offshore joint venture sites, Beatrice and Greater Gabbard, both of which are operated on behalf of asset partners.
- The Proposed Development array area (i.e. the area in which the wind turbines will be located) is approximately 1,010 km2 and is located approximately 37.8 km east of the Scottish Borders coastline (St. Abb’s Head) and 47.6 km to the East Lothian coastline from the nearest boundary (see Figure 1.1 Open ▸ ). The Proposed Development’s array area overlaps the large-scale morphological banks ‘Marr Bank’ and ‘Berwick Bank’.
- A maximum of 307 wind turbines will be installed in the Proposed Development array area, with either suction caisson jacket or piled jacket foundations. There will also be up to ten OSPs/Offshore convertor station platforms which will also be installed on piled jacket or suction caisson jacket foundations. The wind turbines will connect to each other and to the OSPs/Offshore convertor station platforms via subsea inter-array cables, and the OSPs/Offshore convertor station platforms will be connected to other OSPs/Offshore convertor station platforms via interconnector cables.
- Up to eight offshore export cables will connect the OSPs/Offshore convertor station platforms to the landfall on the East Lothian coast, at Skateraw Harbour (hereafter referred to as the ‘Skateraw Landfall’)’. Once the cables make landfall, they will connect to the onshore substation/converter station, and then onto the grid connection point at Branxton, located south-west of Torness Power Station. This grid connection at Branxton will comprise a new 400 kV substation developed by SPEN.
- The Applicant has signed an agreement for an additional grid connection at Blyth, Northumberland, referred to as the Cambois connection. Necessary consents for the Cambois connection (including marine licences) will be applied for separately once further development work has been undertaken on this export cable corridor route and landfall. These applications will be supported by an EIA and Habitats Regulations Appraisal (HRA). The Cambois connection has also been included as a cumulative project for the purposes of the Offshore EIA Report and assessed based on the information available at the point of assessment.
- The construction activities associated with the Proposed Development are anticipated to commence in 2025 and will last for up to 96 months. The decommissioning process is likely to follow a similar programme to construction, in a reverse manner. The Applicant has a 50 year Agreement for Lease (AfL) with Crown Estate Scotland (CES) and therefore, the Applicant is seeking a 35 year consent period to allow the wind farm to continue operating should the lifespan of the wind turbines allow. Further description of the Proposed Development is presented in section 1.3.
1.2. Policy and Legislative Context
- This section presents a summary volume 1, chapter 2 which contains the relevant Policy and Legislation context for the Proposed Development specifically in relation to:
- international obligations and policy, including those derived from European legislation, relating to climate change, reducing greenhouse gas (GHG) emissions and the role of renewable energy;
- UK and Scottish climate change and energy legislation and policy;
- Scottish offshore wind consenting legislation, including the consent applications required for the construction, operation and maintenance, and decommissioning of the Proposed Development; and
- other legislation that may be relevant to the Proposed Development.
- In December 2015, 195 countries adopted the first ever universal, legally binding global climate deal at the Paris climate conference (COP21). The Paris Agreement (2016) sets out a global action plan towards climate neutrality with the aims of stopping the increase in global average temperature to below 2°C above pre-industrial levels, and to pursue efforts to limit global warming to 1.5 C.
European legislation and policy
- On 31 January 2020, the UK formally left the European Union (EU) after triggering article 50 of the Lisbon Treaty (EU Exit). After leaving the EU, the UK Government has committed, as a minimum, to implement international environmental obligations in accordance with the EU (Withdrawal) Act 2018 and to maintain environmental commitments made and legislation enacted following the departure of the UK from the EU (HM Government, 2018).
- On this basis, the existing EU renewable energy targets for the UK, including the EU Renewable Energy Directive (RED) 2009/28/EC will remain applicable. However, new EU legislation or updates to existing directives will not be required to be transposed into UK law. The following sections set out the EU renewable energy targets.
UK climate change and energy legislation
The Climate Change Act 2008
- Under the Climate Change Act 2008, the UK committed to a net reduction in GHG emissions by 2050 of 80% against the 1990 baseline. In June 2019, secondary legislation was passed that extended that target to at least 100% against 1990 baseline by 2050, with Scotland committing to a net zero by 2045. The Climate Change Act 2008 also established the Committee on Climate Change (CCC) which advises the UK government on emissions targets, and reports to Parliament on progress made in reducing GHG emissions. The CCC has produced six four yearly carbon budgets, covering 2008-2037. These carbon budgets represent a progressive limitation on the total quantity of GHG emissions to be emitted over the five year period.
- In December 2020, the UK Government published the Energy White Paper (HM Government, 2020b), which provides a compelling case for tackling climate change, with a substantial increase of offshore wind capacity as part of the Prime Minister’s ten-point plan.
- The UK submitted its Nationally Determined Contribution (NDC) (HM Government, 2020a) to the United Nations Framework Convention on Climate Change (UNFCCC) under the Paris Agreement in December 2020, covering England, Scotland, Wales and Northern Ireland. The UK’s NDC draws on the Clean Growth Strategy (HM Government, 2017), which contains the current policies and measures to decarbonise all sectors of the UK economy through the 2020s and beyond. HM Government (2020c) includes a commitment for a reduction of at least 68% of GHG emissions by 2030 compared to 1990 levels.
- The programme for Scottish Government 2021-2022, which includes a chapter on how Scotland proposes to end its contribution to climate change, was published in September 2021 (Scottish Government, 2021a). This report considers offshore wind as a key contributor towards this goal. Furthermore, Scotland’s Climate Change Plan 2018-2032 was updated in 2020 (Scottish Government, 2020a), listing policies and proposals which contribute towards reducing GHG emissions and meeting Scotland’s target for net zero. The Proposed Development is considered to be a key project to help towards the end goal of reducing Scotland’s contribution to climate change and achieving net zero within the target dates set out within Government policy.
The Energy Act 2013
- The Energy Act 2013 makes provisions to incentivise investment in low carbon electricity generation, ensure security of supply, and help the UK meet its emission reduction and renewables targets.
- The Energy Act contains provisions for Electricity Market Reform (EMR), which sets out the framework for replacing Renewables Obligation Certificates (ROCs) with Contracts for Difference (CfD) to provide stable financial incentives to encourage investment in low carbon electricity generation.
- CfDs are private contracts between a low carbon electricity generator and the UK Government owned Low Carbon Contracts Company (LCCC). The aim of the CfDs is to give greater certainty and stability of revenues to electricity generators by reducing exposure to volatile wholesale prices, whilst protecting the consumer from paying for higher generation support costs when electricity prices are high (Department for Business, Energy and Industrial Strategy (BEIS), 2021). CfDs aim to support development of renewable energy in the UK by incentivising development.
UK Marine Policy Statement
- The UK wide Marine Policy Statement (MPS) was published in March 2011 and updated in September 2020, under Section 44 of the Marine and Coastal Access Act (MCAA) 2009, to provide a framework for marine spatial planning, specifically for the preparation of Marine Plans and to ensure that marine resources are used in a sustainable way (HM Government, 2011). The MPS was jointly adopted by Scottish Ministers, the Secretary of State, Welsh Ministers and the Department of the Environment Northern Ireland (DOENI). The MPS confirms that all public authorities, in examining and determining applications for all energy infrastructure, the relevant marine policy statement must be followed, and the following must be considered:
- the national level of need for energy infrastructure;
- the positive wider environmental, societal and economic benefits of low carbon electricity generation;
- that renewable energy resources can only be exploited where the resource exists and where economically feasible; and
- the potential for inward investment on energy related manufacturing and deployment activity and employment opportunities and regeneration of local national economies, supporting the objective of developing the UK’s low carbon manufacturing capability.
- The MPS states that renewable energy offers the potential for significant broad scale environmental benefits through mitigating GHG emissions. When considering potential benefits and adverse effects, decision makers should also consider any cumulative impacts of the proposals with other projects and activities. The MPS also confirms that the level of assessment undertaken for any project should be proportionate to the scale and potential impact of the project, as well as the sensitivity of the environment concerned and in accordance with the EIA Directive, where applicable.
UK Offshore Wind Sector Deal
- The UK Government published the Offshore Wind Sector Deal in 2019, which sets out the key commitments and actions from the UK Government to support offshore wind energy development (HM Government, 2019). The Sector Deal is divided in terms of ideas, people, infrastructure, business environment and places, laying key commitments for each of these. In relation to infrastructure, it investigates:
- how clean, affordable energy is essential for economic prosperity;
- the need to reduce energy costs for consumers;
- how to deliver up to 30 GW of energy in a sustainable way; and
- the plans for offshore wind energy beyond 2030.
- In 2020, the UK Government prepared a policy paper to reflect on the status of the offshore wind industry one year after the publication of the Offshore Wind Sector Deal (HM Government, 2020).
Scottish policy and legislation
- The following policy and legislation documents relate to specifically to Scotland and are listed below to provide a brief guide to further legislation at a Scottish Level
- The Climate Change (Scotland) Act 2009 and Climate Change (Emissions Reduction Targets) (Scotland) Act 2019:
– introduces binding targets on the Scottish Government to reduce net Scottish GHG emissions by at least 100% by 2045 from 1990 levels;
- The Scottish Energy Strategy: The Future of Energy in Scotland (Scottish Government, 2017):
– sets out the Scottish Government’s vision for the future energy system in Scotland and outlines six priorities around Scotland’s 2050 vision which includes renewable and low carbon energy solutions.
- National Planning Framework (NPF) 3 (Scottish Government, 2014a):
- Scottish Planning Policy (SPP) (Scottish Government, 2014b):
– supports the NPF 3 and sets out national plans and strategies to provide a vision of how Scotland should evolve in the future.
- The draft NPF 4 (Scottish Government, 2022):
– currently out for consultation, sets out the approach to planning and development in support of achieving net zero in Scotland by 2045
- Scotland’s Offshore Wind Route Map (OWIG, 2010):
– the Offshore Wind Industry Group (OWIG) (consisting of industry, government, and public sector bodies) published Scotland’s Offshore Wind Route Map in 2010 to illustrate the opportunities, challenges and recommendations; and
– the route map presented recommendations to support offshore wind making a significant contribution to the now superseded target of achieving 80% of Scotland’s electricity consumption coming from renewable sources by 2020.
Scottish marine planning policy
- The Scottish Government has introduced a system of marine planning that covers Scottish offshore waters (12 nm to 200 nm) waters under the MCAA 2009 and territorial waters (within 12 nm) under the Marine (Scotland) Act 2010. Decisions are made based on these Acts and in accordance with the appropriate Marine Plans, which are summarised below.
- Scottish National Marine Plan:
– the Scottish National Marine Plan (NMP) was adopted in 2015, covering the management of both Scottish inshore waters (within 12 nm) and offshore waters (12 nm to 200 nm); and
– the NMP “sets out strategic policies for the sustainable development of Scotland’s marine resources and is compatible with the UK MPS and existing Marine Plans across the UK” (Marine Scotland, 2015).
- Scottish Marine Regions (SMRs):
– eleven SMRs have been created covering sea areas extending out to 12 nm (the Proposed Development lies within the Forth and Tay SMR).
- Regional Marine Plans (RMP):
– RMPs are being developed at a regional level within SMRs by Marine Planning Partnerships, to take account of local circumstances and smaller ecosystem units; and
– at the time of writing (October 2022), there is no RMP in place for the region.
- Sectoral Marine Plan for Offshore Wind Energy:
– the SMP seeks to contribute to the achievement of Scottish and UK energy and climate change policy objectives and targets, through the provision of a spatial strategy to inform the seabed leasing process for commercial offshore wind energy in Scottish waters.
- This section provides a summary of the consenting process and associated legislative requirements being followed for the Proposed Development.
- As the Proposed Development is a generating station with a capacity of greater than 50 MW, it requires Section 36 consent under the Electricity Act 1989.
- The Proposed Development also requires the following:
- a marine licence under the MCAA 2009 for the generating station including wind turbines, foundations and inter-array cables;
- marine licence(s) for the offshore transmission infrastructure (OSPs/Offshore convertor station platforms, interconnector cables and offshore export cables) under the Marine (Scotland) Act 2010 for infrastructure in Scottish inshore waters (0-12nm) and the MCAA 2009 for infrastructure in Scottish offshore waters (12-200 nm); and
- planning permission under the Town and Country Planning (Scotland) Act 1997 for all infrastructure located landward of Mean Low Water Springs (MLWS).
Section 36 Consent
- As the Proposed Development is an offshore generating station greater than 50 MW capacity and located in the Scottish offshore waters (12 nm to 200 nm) within the Scottish Renewable Energy Zone (REZ), there is a requirement for consent under Section 36 of the Electricity Act 1989. Section 36 will allow for the installation, operation and maintenance of Infrastructure associated with the Proposed Development (see section 1.3 for further details).
- The MCAA 2009 applies within the REZ in UK offshore waters (12 nm to 200 nm). Under the MCAA 2009 there is the requirement for a marine licence to be obtained prior to the construction, alteration or improvement of any works or deposit of any object in or over the sea, or on or under the seabed (HM Government, 2009).
- Similarly, under the Marine (Scotland) Act 2010, which applies to Scottish territorial waters (between 0 nm and 12 nm from MHWS), there is also the requirement for a marine licence prior to the construction, alteration or improvement of any works or deposit any object in or over the sea, or on or under the seabed (HM Government, 2010).
- Landward of MLWS, works associated with the Proposed Development will require consent under the Town and Country Planning (Scotland) Act 1997. Separate offshore and onshore applications will be made to Marine Scotland and ELC, respectively, the latter being a single application for full planning permission, in accordance with the Town and Country Planning (Scotland) Act 1997. It is currently anticipated that both these applications will be made in 2022.
- The Applicant is also developing an additional export cable and grid connection to Blyth, Northumberland (hereafter the “Cambois connection”). Applications for the necessary consents (including marine licences) will be applied for separately once further development work has been undertaken on this offshore export cable corridor. The Cambois connection has been assessed as a cumulative project in relation to the Proposed Development. A separate EIA Report will be prepared to support any relevant consent applications that are required to deliver the Cambois connection which will also consider cumulative effects with the Proposed Development.
- Under the EIA process, an EIA Report is required to be prepared and submitted to support applications for a Section 36 consent, a marine licence or planning permission relating to offshore renewable energy developments if the proposed activities are likely to have a significant effect on the environment due to factors such as the size, nature or location of the proposal. The purpose of the EIA Regulations is to ensure that any consenting authority gives due consideration to likely significant effects on the environment when considering consenting a proposed project. Due to the size, scale and location of the Proposed Development an EIA is required and an EIA Report has been submitted as part of the section 36 and marine licence applications.
- The Council Directive (92/43/EEC) (the Habitats Directive) was adopted in 1992, providing a means for the EU to meet its obligations under the Bern Convention. The Habitats Directive provides for the conservation of natural habitats and of wild flora and fauna, including offshore waters. This protection is granted through the designation of European sites and European Protected Species (EPS).
- The European Directive (2009/147/EC) on the conservation of wild birds (The Birds Directive) provides a framework for the conservation and management of wild birds in Europe, including their eggs, nests and habitats.
- The Habitats Regulations transpose the Habitats and Birds Directives into law in the UK. Under the Habitats Regulations, a network of protected sites for birds and certain habitats and species have been established in the UK. Following EU Exit, the network of sites is collectively known as the Natura 2000 network (where the sites are located within Member State countries) and the National Site Network (or UK site Network) where the sites are located within the UK. These sites are hereafter collectively (whether located in the UK or the EU) referred to as ‘European sites’ and include:
- Special Areas of Conservation (SACs) or candidate SACs;
- Special Protection Areas (SPAs) or proposed SPAs;
- Sites of Community Importance (SCIs); and
- Ramsar sites (where also designated as one of the above).
Habitats Regulations Appraisal
- Where a plan or project is likely to have a significant effect on a European site, regardless of whether the project location is within or beyond the 12 nm boundary, there is a requirement, under the Habitats Regulations for the competent authority (Marine Scotland) to carry out an Appropriate Assessment.
- The Habitats Regulations require sufficient information to be provided the competent authority to enable it to assess whether there are likely to be any significant effects, and to carry out the Appropriate Assessment (and any subsequent stages of the HRA), where necessary, as part of an HRA. This information and the legislative and policy background to the assessment is provided by the Applicant in the Berwick Bank Wind Farm Report to Inform Appropriate Assessment (RIAA) which accompanies the Offshore EIA Report.
European Protected Species licence
- EPS are animals and plants (species listed in Annex IV of the Habitats Directive and referred to in the schedules of the Habitats Regulations) that are afforded protection under the Habitats Regulations. All cetacean species (whales, dolphins and porpoise) are EPSs. If any activity is likely to cause disturbance or injury to an EPS, a licence is required to undertake the activity legally.
Energy Act 2004
- Safety Zones:
– safety zones are intended to ensure the safety of the renewable energy installation or other installations in the vicinity during construction, operation, extension or decommissioning. They may exclude non-project vessels from navigating through a designated area for a designated period.
– sections 105 to 114 of the Energy Act 2004 (as amended by the Energy Act 2008 and the Scotland Act 2016) (hereafter referred to as the Energy Act) contain statutory requirements in relation to the decommissioning of Offshore Renewable Energy Installations (OREIs) and their related electricity lines; and
– under the terms of the Energy Act, Scottish Ministers may require a person who is responsible for these installations to prepare (and carry out) a costed decommissioning programme for submission to and approval by Scottish Ministers (Scottish Government, 2019).
Marine Strategy Framework Directive
- The Marine Strategy Framework Directive (MSFD) requires Member States to prepare national strategies to manage their seas to achieve Good Environmental Status (GES) by 2020.
Water Framework Directive regulations
- In the UK, coastal waters are protected under the Water Framework Directive (WFD) which requires that “the project or activity does not cause or contribute to deterioration in water body status or jeopardise the water body achieving good status” (UK Government, 2016).
- The European Commission (EC) WFD has become law in Scotland as the Water Environment and Water Services (Scotland) Act 2003. This legislation covers certain activities in coastal waters (3 nm from the limit of the highest tide) (Scottish Environment Protection Agency (SEPA), 2021).
Marine Protected Areas (MPAs)
- The Marine (Scotland) Act 2010 and the MCAA 2009 introduced provisions to designate and support the management of Nature Conservation (nc) Marine Protected Areas (MPAs). Under section 126 of the MCAA 2009 and section 83 of the Marine (Scotland) Act 2010, Marine Scotland Licencing Operations Team (MS-LOT), as the public authority, is required to consider whether an activity is capable of affecting (other than insignificantly) a protected feature in a ncMPA or any ecological or geomorphological process on which the conservation of any protected feature in a ncMPA is dependant.
Pre-Application Consultation (PAC)
- Where activity is planned within the Scottish Territorial Waters, the Marine Licensing (Pre-application Consultation) (Scotland) Regulations 2013 (hereafter referred to as the PAC Regulations) apply. There is no provision for PAC in the MCAA 2009, so these requirements do not apply in respect of relevant applications in the Scottish Offshore Region. There are no statutory requirements for consultation during the pre-application stage for Section 36 consent applications, however the principles of the PAC Regulations will be followed for all offshore components of the Proposed Development (below MHWS). The stakeholder engagement and public consultation carried out in relation to the Proposed Development is detailed in section 1.5.
1.3. Project Description
- This section provides a summary of volume 1, chapter 3, which the description of the offshore components and methodology for the Proposed Development.
- As described in section 1.1, this Offshore EIA Report has followed the PDE approach, which provides flexibility by assessing the project on the basis of the maximum project design parameters, while ensuring all likely significant effects are assessed within the EIA. Based on this, the Project Description (volume 1, chapter 3) and this summary present the maximum extents of the design as a basis to determine what the likely worst case effects may be, noting that for some technical topics the worst case might be a combination of parameters, not just the maximum parameter, as explained and assessed in volume 2, chapters 7 to 21.
1.3.2. Offshore Infrastructure
- The Proposed Development will be located in the central North Sea, at least 47.6 km offshore of the East Lothian coastline and 37.8 km from the Scottish Borders coastline at St, Abbs. The Proposed Development is already the subject of AfL from CES, and its operational lifetime is assumed to be up to 35 years.
- The Proposed Development will comprise of the following key offshore components:
- up to 307 wind turbines (each comprising a tower section, nacelle and three rotor blades) and associated support structures and foundations;
- up to ten OSPs/Offshore convertor station platforms and associated support structures and foundations to accommodate for a combined High Voltage Alternating Current (HVAC)/High Voltage Direct Current (HVDC) transmission system solution or a HVDC solution;
- a network of inter-array cabling linking the individual wind turbines to each other and to the OSPs/Offshore convertor station platforms plus inter-connections between OSPs/Offshore convertor station platforms (approximately 1,225 km of inter-array cabling and 94 km of interconnector cabling); and
- up to eight offshore export cables connecting the OSPs/Offshore convertor station platforms to landfall at Skateraw.
- Figure 1.2 Open ▸ presents an overview of the main offshore components of the Proposed Development.
- Wind turbines will comprise a horizontal axis rotor with three blades connected to the nacelle of the wind turbine. The maximum rotor blade diameter will be no greater than 310 m, with a maximum blade tip height of 355 m above Lowest Astronomical Tide (LAT) and a minimum blade tip clearance of 37 m above LAT. The layout of the wind turbines will be developed to best utilise both the available wind resource, suitability of seabed conditions and wake effects, while seeking to minimise environmental effects and impacts on other marine users (such as fisheries, shipping routes and Search and Rescue (SAR) operations) where possible.
- The Proposed Development will require up to ten OSPs/Offshore convertor station platforms, which transform electricity generated by the wind turbines to a higher voltage and thereby allowing the power to be efficiently transmitted to shore. The size of the platforms’ topsides will depend on the final electrical design for the Project but maximums could be up to 100 m (length) by 80 m (width), and up to 80 m in height (above LAT), excluding the helideck, antenna structure or lightning protection. The maximum design parameters for OSPs/Offshore convertor station platforms are presented in volume 1, chapter 3. It is proposed that the OSP/Offshore convertor station platform foundations will be painted yellow from the water line up to the topside structure and the topside will be painted light grey.
- Wind turbines and OSPs/Offshore convertor station platforms will comprise either piled jacket or suction caisson jacket foundations. The final choice of foundation will depend on ground conditions, wave and tidal conditions, economic factors and procurement approach. Scour protection will be installed around the foundations to prevent seabed erosion and the development of scour holes. Several forms of scour protection are being considered, which include concrete mattresses, rock placement and artificial fronds.
- Inter-array cables will carry the electrical current produced by the wind turbines to the OSP/Offshore convertor station platforms. It is proposed that up to a maximum of 1,225 km of inter-array cabling will be required for the Proposed Development.
- Interconnector cables will be required to connect the OSPs/Offshore convertor station platforms to each other. The cables are likely to consist of a cross-linked polyethylene (XLPE) insulated aluminium or copper conductor submarine cable.
- Offshore export cables are used for the transfer of power from the OSPs/Offshore convertor station platforms to the transition join bay at landfall (located above MHWS and to be included in the Projects Onshore Planning application) where they become onshore export cables. The offshore export cables will have a maximum total length of 872 km, comprised of up to eight cables connecting the OSPs/Offshore convertor station platforms to landfall at Skateraw. Although the Proposed Development export cable corridor has been identified, the exact route of the offshore export cables is yet to be determined and will be based upon geophysical and geotechnical survey information.
- Cable protection will be used to prevent movement of the cables over the lifetime of the Proposed Development and provide protection to cables when target cable burial depths are not achieved due to seabed conditions. This will protect cables from other activities such as fishing or anchor placement, dropped objects, and limit the effects of heat and/or induced magnetic fields.
- Up to 16 cable crossings may be required for the offshore export cables. Each of the eight offshore export cables will cross the two Neart na Gaoithe (NnG) Offshore Wind Farm export cables. This will be facilitated by the installation of standard cable crossing designs, likely to be comprised of ducting, concrete mattresses or rock. It is also possible that up to 78 inter-array cable crossings will be required, using measures identified above.
1.3.3. Site Preparation Activities
- Geophysical and geotechnical surveys will be carried out across the Proposed Development array area and Proposed Development export cable corridor to identify in detail:
- seabed conditions and morphology;
- presence/absence of any potential obstructions or hazards; and
- to inform detailed project design work.
Clearance of unexploded ordnance
- The presence of Unexploded Ordnance (UXO) poses a health and safety risk where it coincides with the planned location of infrastructure and associated vessel activity, and therefore it is necessary to survey for and carefully manage UXOs.
- Where it is not possible to avoid or relocate a UXO, the preferred method for UXO clearance is for a low order technique. Further information on this is provided in volume 1, chapter 3 and volume 2, chapter 10.
Sand wave and boulder clearance
- There might be a requirement to remove existing sand waves and similar bedforms within the Proposed Development array area and along the Proposed Development export cable corridor before cables can be installed. Sand wave clearance may take place throughout the construction phase. Further information is provided in volume 1, chapter 3.
- Boulder clearance is commonly required during offshore wind farm site preparation. A boulder is typically defined as being over 200 mm in diameter/length. Boulder clearance may be required along the inter-array cables, OSP/Offshore convertor station platform interconnector cables and the Proposed Development export cable corridor. It may also be required in the vicinity of the foundation locations (including within the jack-up vessel zone around the foundation locations), in order to avoid disruption to installation activities and to ensure stability for the jack-up vessel. Furthermore, offshore cable routes may be pre-ploughed for the removal of discreet boulders. Should more dense boulder fields be encountered, there may be a need for additional techniques such as the use of boulder grabs This decision will be informed by the geophysical and pre-construction surveys.