3. Site Selection Methodology and Consideration of Alternatives

Site Selection Methodology and Consideration of Alternatives

3.1. Introduction

  1. This section discusses the site selection and alternatives of the Array which have been considered by the Applicant. The stages of site selection that have been carried out to establish the Array will be further outlined in the Array Environmental Impact Assessment (EIA) Report. In addition, any refinements to the Array that have taken place resulting from the EIA process and in response to consultation and stakeholder feedback will be included in the Array EIA Report, and the reasonable alternatives that have been considered as part of this process will be discussed.

3.2. Site Selection And Consideration Of Alternatives

  1. CES announced its intention to launch a leasing round for commercial scale offshore wind energy projects within Scottish waters in November 2017 (Scottish Government, 2020a). The first ScotWind Leasing Round was subsequently launched by CES in June 2020. The ScotWind Leasing Round allowed developers to apply for the rights to build offshore wind farms in Scottish waters within specified lease areas, with up to 25 GW of new generating capacity expected to be built over the following ten years. The application window for registered applicants opened in January 2021 and closed in July 2021, with Option to Lease Agreements offered in January 2022.
  2. In October 2020, the Scottish Government published the Sectoral Marine Plan (SMP) for Offshore Wind Energy which provided a strategic framework for the ScotWind Leasing Round (Scottish Government, 2020a). The SMP identified 15 final Plan Options (POs) across four regions for renewable energy generation, with a national limit on generating capacity of 10 GW.
  3. These final POs were developed through an iterative process. The first steps included identification of initial Areas of Search (AoS) which were subsequently refined through several iterations of Opportunity and Constraint Analysis, and consultation and engagement with key sectoral stakeholders, Scottish Ministers, the SMP Project Board and Project Steering Groups. From this, 17 revised AoS were selected as Draft Plan Options (DPOs) (Scottish Government, 2020a).
  4. The DPOs were subject to a Sustainability Appraisal process, comprising a Strategic Environmental Assessment (SEA), Habitats Regulations Appraisal (HRA) and Social and Economic Impact Assessment (SEIA), which examined cross-sectoral impacts of the DPOs to support sustainable development of renewable energy generation in Scottish waters. Statutory consultation was held between 18 December 2019 and 25 March 2020 to seek feedback on the DPOs. A Consultation Analysis Report was produced to inform the Scottish Ministers' decision on which DPOs to progress (Scottish Government, 2020d). Following this, the SMP was published, and the refined, final POs were identified within this (Scottish Government, 2020a). 
  5. The SMP noted that there was potential for regional cumulative impacts on bird populations, benthic habitats, cetaceans, navigational safety, seascape/landscape, and commercial fisheries, however, the level of impacts are likely to vary depending upon the final POs developed. The SMP provides several mitigation measures regarding potential impacts at various scales (Scottish Government, 2020a).
  6. The SMP was developed in accordance with the aims of the National Marine Plan (NMP) (Scottish Government, 2015) and sits alongside the Scottish Offshore Wind Energy Policy Statement (OWEPS) (Scottish Government, 2020b) to build a framework towards Scotland’s sustainable green recovery. It should be noted that the SMP is subject to an iterative review process (Scottish Government, 2020a).
  7. The Applicant applied for the rights to develop an offshore wind farm within the E1 PO Area in the first ScotWind Leasing Round, and was subsequently awarded an Option to Lease Agreement for the site boundary, within which the Array will be located, in January 2022. The Applicant applied to develop the site boundary within the E1 PO Area based on a detailed review of number of parameters and constraints (SSER, Marubeni and CIP, 2021) including:
  • water depth and distance to shore;
  • wind speed and metocean conditions;
  • offshore geotechnical conditions;
  • offshore environmental designations (existing and proposed) including Special Protection Areas (SPAs), Ramsar sites, Sites of Special Scientific Interest (SSSIs), Special Areas of Conservation (SACs) and Nature Conservation Marine Protected Areas (NCMPAs);
  • ornithology;
  • offshore habitats;
  • benthic ecology, including epifauna and infauna;
  • fish and shellfish ecology;
  • marine mammals including cetaceans and seals;
  • shipping and navigation
  • commercial fishing effort;
  • seascape and landscape;
  • archaeology and cultural heritage;
  • aviation and radar, including civil and military aspects;
  • existing infrastructure and oil and gas leases;
  • energy generation;
  • emergency services, including search and rescue (SAR) operations; and
  • cables and pipelines.
  1. The site boundary was selected by the Applicant for application after undergoing a site assessment process which used measured baseline data from Berwick Bank, Seagreen 1 (formerly known as Seagreen Alpha and Bravo), and Seagreen 1A Offshore Wind Farm projects, industry-leading tools including a Levelised Cost of Energy (LCoE) analysis of all 15 of the final POs included in the ScotWind Leasing Round, as well as an assessment of wind resource and energy yield prediction, and drew upon their extensive experience developing offshore wind globally and in Scotland (SSER, Marubeni and CIP, 2021).
  2. According to the SMP, the key concerns within the E1 PO Area included minor socio-economic impacts to commercial shipping, fishing, power interconnector sectors, and Ministry of Defence (MoD) radar interference, as well as impacts to offshore ornithology (in particular kittiwake Rissa tridactyla and razorbill Alca torda) and fish spawning grounds for herring Clupea harengus, cod Gadus morhua, whiting Merlangius merlangus, plaice and sandeel Ammodytes spp. (Scottish Government, 2020a). Therefore, the Applicant carried out several studies and analyses at the pre-award stage to gain an understanding of the potential constraints associated with the site boundary, as noted in the SMP.
  3. Analysis was undertaken to understand the metocean conditions within the area, followed by the deployment of metocean buoys within the site boundary in August 2022. The Applicant also assessed the wind and climatic conditions regarding site suitability and project feasibility, and commissioned Atkins to carry out a desktop geological and foundations feasibility assessment of the E1 PO Area. This desktop study concluded that the area of the site boundary was the best location for the development of a floating offshore wind farm based on desk-based data and taking into consideration the various constraints within the region. The Applicant has followed this with an interpretive geophysical survey and environmental survey (including benthic grab sampling and drop down video (DDV)) of the site boundary between March and July 2022. In addition, the Applicant also undertook a desktop study of other infrastructure in the area, including oil and gas, cables and pipelines and energy generation (SSER, Marubeni and CIP, 2021).
  4. The Applicant began aerial ornithological and marine mammal surveys, prior to award, in February 2021, to gain an understanding of the ornithological and marine mammal baseline. This two-year survey is expected to conclude in February 2023 and will inform the design considerations and layout of the Array which will be taken forward into the Array EIA Report. Regional level ornithological surveys are also in progress, as proposed in the SMP.
  5. In addition, the Applicant also commissioned several studies at the pre-award stage to gain an early understanding of the potential risks to human receptors within the site boundary, as follows:
  • a shipping activity and constraints study, carried out by Anatec Ltd (Anatec Ltd., 2021);
  • a fishing intensity and spawning analysis study, carried out by Brown and May Marine Ltd (Brown and May Marine Ltd., 2021); and
  • an aviation and military activity study, carried out by Coleman Aviation.
  1. Further desktop data analysis and studies will be carried out throughout the EIA process and documented in the standalone Technical Reports for the various receptor topics, as well as feeding into the assessments undertaken within the Array EIA Report.
  2. The Array EIA Report will further describe the background to the ScotWind leasing round process and the evolution of the Array within the site boundary. In addition, the Array EIA Report will outline the process followed by the Applicant to identify potential wind turbine layouts and other infrastructure forming part of the Array application including Offshore Substation Platforms (OSPs), inter-array cables and interconnector cables, the reasonable alternatives that were considered, and the rationale for the selection of the final project design considering any modifications identified during consultation.
  3. In 2020, the Offshore Transmission Network Review (OTNR) was launched by the UK Government and is currently ongoing. The purpose of the OTNR is to ensure that the network connections for offshore wind generation are delivered efficiently and consider environment, cost to consumers, local communities and deliverability (HM Government, 2022a; National Grid, 2022a). In April 2022, the UK Government released the British Energy Security Strategy policy paper which sets out the ambition to deliver up to 50 GW of offshore wind by 2030, including up to 5 GW of floating offshore wind (HM Government, 2022b). To achieve this ambitious target, it is necessary that a coordinated approach with regard to the offshore grid network and landfall points is put forward. As part of the OTNR, National Grid have developed the Pathway to 2030 Holistic Network Design (HND) to set out a coordinated approach for connecting 23 GW of offshore wind (National Grid, 2022a). The findings of the HND will feed into a Detailed Network Design (DND) which will be taken forward by the organisation(s) responsible for developing that part of the network, and a HND Follow Up Exercise (HNDFUE) will be undertaken by National Grid to include the remaining ScotWind leaseholders, any capacity available through the ScotWind clearing process, and 4 GW of Celtic Sea Floating Offshore Wind (FLOW) capacity (National Grid, 2022b).
  4. Due to the ongoing nature of the OTNR and HNDFUE, and the uncertainty associated with landfall grid connection points, the Applicant has made the decision for the Proposed offshore export cable corridor(s) and Proposed onshore export cable corridor(s) (and associated onshore transmission infrastructure) to be subject of separate applications once the outcomes and/or further information of these reports are available.