1.4. Ossian Project TeamOssian Project Team

1.4.1. Ossian OWFLOssian OWFL

  1. Ossian OWFL is a joint venture between SSER, CIP and Marubeni.
  2. SSER 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. SSER owns nearly 2 GW of operational onshore wind capacity with over 1 GW under development.
  3. Its operational offshore wind portfolio consists of 487 MW across two offshore joint venture sites (Beatrice and Greater Gabbard), both of which it operates on behalf of its joint venture partners. SSER has the largest offshore wind development pipeline in the UK and Ireland at over 8 GW.
  4. SSER is currently constructing the world’s largest offshore wind energy project, the 3.6 GW Dogger Bank Wind Farm in the North Sea, 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. SSER is also at the planning stage of the Berwick Bank Wind Farm, which will be one of the world’s largest wind farm developments once built, generating up to 4.1 GW of power, with the planning application submitted to the Scottish Government in December 2022.
  5. CIP is the world’s largest fund manager dedicated to the renewable energy sector. To date, it has raised approximately £17 bn for investments in green energy and associated infrastructure.  In the last decade, it has invested more than £1.5 bn in large-scale renewable energy projects in the UK, with future planned investments across the UK potentially requiring an additional £5bn - £10 bn.  These include onshore wind and associated grid infrastructure in Wales, and large-scale battery energy storage projects at various locations in Scotland and England.  CIP expects to be a lead investor and provider of capital for these projects, demonstrating its strong interest for further investment in the UK.
  6. CIP also has considerable interests in floating offshore wind opportunities globally.  In addition to Ossian, CIP has expressed interest in the current Crown Estate leasing opportunity for 4 GW of Floating Offshore Wind (FLOW) in the Celtic Sea.  CIP was also recently announced (through its fund Copenhagen Infrastructure IV and its affiliate California North Floating, Limited Liability Company (LLC)) as the provisional winner of a lease area in the auction held by the United States (US) Bureau of Ocean Energy Management (BOEM).  The auction was the first-ever offshore wind lease sale on the US West Coast and the first-ever US sale to support potential commercial-scale floating offshore wind energy development.  CIP also has interests in the Scipio and Hannibal projects, (respectively, 500 MW and 250 MW floating wind developments off the coasts of Sicily and Sardinia, Italy).
  7. Through its exclusive development partner Copenhagen Offshore Partners (COP), it is also currently developing the 100 MW Pentland FLOW project off the Caithness coast, Scotland.  To aid the delivery of these projects and furtherment of its growing interest in FLOW, COP will officially open its Floating Offshore Wind Competence Centre in Edinburgh in Spring 2023.
  8. Marubeni is a Japanese conglomerate which is involved in third country trading and domestic business across a range of sectors (Marubeni, 2022a). Included within Marubeni’s extensive portfolio is their involvement in developing and operating over 2 GW of onshore and offshore wind farms to date. Marubeni’s core competencies with regard to the offshore wind business include Engineering, Procurement and Construction (EPC), construction management, operation and maintenance, project financing and coordination with stakeholders (Marubeni Offshore Wind Development, 2023).
  9. Marubeni has been instrumental in the delivery of Japan’s first large-scale bottom fixed offshore wind farms at Akita Port and Noshiro Port in Akita Prefecture as part of the Akita Offshore Wind Corporation. As part of this project, Marubeni was responsible for development, construction, operation and maintenance, and financing of the project, with a total of 33 wind turbine units constructed and total output of 140 MW (Marubeni, 2022b). The Noshiro Port Offshore Wind Farm and the Akita Port Offshore Wind Farm started commercial operation in December 2022 and January 2023, respectively (Akita Offshore Wind Corporation, 2022).
  10. Marubeni has also been involved in two Japanese government sponsored floating offshore wind demonstration projects off the coast of Fukushima and Kitakyushu, respectively (Marubeni, 2022b). The Fukushima Floating Offshore Wind Farm was operational between 2013 and 2020, consisting of three floating turbines with total capacity of 14 MW and one floating substation installed 20 km off the coast of Naraha-town (Fukushima prefecture) at a water depth of approximately 100 m. The Kitakyushu Floating Offshore Wind Farm began operating in 2019, consisting of one floating turbine installed 15 km off the coast of Kitayushu-city (Fukuoka prefecture) at approximately 50 m water depth. Marubeni managed the project consortiums for these projects, as well as taking a lead role in consenting and permitting, economics analysis, operation and maintenance, and coordination with fisheries (Marubeni Offshore Wind Development, 2023).

1.4.2. The Project EIA TeamThe Project EIA Team

  1. RPS has been instructed by the Applicant to lead the Offshore EIA for the Array. This includes the initial review of the key environmental issues associated with the construction, operation and maintenance, and decommissioning of Ossian that have formed the basis of this Scoping Report, and the subsequent Array EIA Report.

1.5. Policy and LegislationPolicy and Legislation

  1. An overview of the relevant policy and legislation to the Array is presented below. Further details can be found in Appendix 4.

1.5.1. Need for the DevelopmentNeed for the Development

                        International commitments

  1. The Kyoto Protocol came into effect in 2005, which sets internationally binding emission reduction targets and commits state parties to reduce greenhouse gas (GHG) emissions. The UK is a signatory of this Protocol, with its commitments transposed into UK law by the Climate Change Act 2008. This initially required the net UK greenhouse gas emissions for the year 2050 to be 80% lower than the 1990 baseline, however, this was subsequently revised by The Climate Change Act 2008 (2050 Target Amendment) Order 2019 to a “net zero target” of greenhouse gas emissions for the year 2050 to be 100% lower than the 1990 levels. In Scotland, the net zero target must be delivered by 2045 (the Climate Change (Scotland) Act 2009).
  2. The Paris climate conference (COP21), held in December 2015, established the first-ever universal, legally binding global climate deal which was adopted by 195 countries. The Paris Agreement (2016), arising out of COP21, sets out a global action plan towards climate neutrality with the aims of limiting 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.

                        UK and Scotland climate change and energy legislation

  1. In addition to the Acts noted in paragraph 49, the UK and Scotland are committed to various other targets within legislation including the following:
  • 2030 Targets including European Union Renewables Energy Directive;
  • 2050 Low Carbon Economy;
  • The Energy Act 2013;
  • British Energy Security Strategy 2022 (HM Government, 2022a);
  • UK Energy Security Bill (under review by the House of Lords at time of writing) (UK Parliament, 2023); and
  • The Scottish Energy Strategy 2017 (Scottish Government, 2017).

1.5.2. Planning LegislationPlanning Legislation

  1. The following consents, licences and permissions are required for the Array:
  • a Section 36 consent under the Electricity Act 1989; and
  • a marine licence(s) for generation assets under the MCAA 2009.
  1. If additional pre-construction licences are required, discussion and agreement with the relevant consenting authority will be undertaken during the pre-construction phase of the Array.

                        Section 36 consent

  1. As the Array is an offshore generating station with a capacity of greater than 50 MW located in Scottish offshore waters (between 12 nm and up to 200 nm offshore) within the Scottish Renewable Energy Zone (REZ), there is a requirement for consent under Section 36 of the Electricity Act 1989. Section 36 consent allows for the construction and operation of the wind turbines, inter-array cables and interconnectors forming part of the Array.

                        Marine licence

  1. The MCAA 2009 applies within the UK offshore waters (between 12 nm and up to 200 nm offshore). It gives the Scottish Ministers executively devolved powers in the Scottish Offshore region (12 nm to 200 nm). Under the MCAA 2009 (as amended) a marine licence must be obtained prior to the construction, alteration or improvement of any works, deposit of any substance or object in or over the sea, or on or under the seabed, or to carry out activities such as dredging.
  2. If applications for both a marine licence under the MCAA 2009 and consent under Section 36 of the Electricity Act 1989 are made where the Scottish Ministers are the determining authority, a note may be issued to the applicant stating that both applications will be subject to the same administrative procedure. In this case, this ensures that the two related applications may be considered at the same time.

                        Environmental Impact Assessment Regulations

  1. Through The Marine Environment (EU Exit) (Scotland) (Amendment) Regulations 2019, which came into force on EU Exit Day (31 January 2020), the requirements established under the EIA Directive (2011/92/EU, as amended by Directive 2014/52/EU) (as transposed into UK law) continue to be applicable, subject to only minor changes. Therefore, the Directive continues to set the framework for the EIA process in Scotland and is relevant to any application in Scottish waters for a Section 36 consent or a marine licence.
  2. The following statutory instruments implement the EIA Directive into Scottish law:
  • in respect to a Section 36 consent application: The Electricity Works (Environmental Impact Assessment) (Scotland) Regulations 2017; and
  • in respect to a marine licence application: The Marine Works (Environmental Impact Assessment) Regulations 2007.
  1. When applying for Section 36 consent or a marine licence, there is a requirement for an EIA Report to be prepared and submitted to support applications where the proposed development is likely to have a significant effect on the environment due to factors such as its size, nature or location, to comply with the aforementioned Regulations. For installations for the harnessing of wind power for energy production (wind farms), an EIA is required (Schedule 2).

1.5.3. The Habitats Directive, Bird Directive and Associated RegulationsThe Habitats Directive, Bird Directive and Associated Regulations

  1. In 1992, Council Directive 92/43/EEC (The Habitats Directive) was adopted, which allowed the EU to meet its obligations under the Bern Convention. The Directive aims to maintain or restore natural habitats and wild species listed on the Annexes at a favourable conservation status, with protection granted through designation of European Sites (Special Areas of Conservation (SACs)) 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 within Europe. Rare and vulnerable species listed under Annex I of the Birds Directive, and regularly occurring migratory species, are given protection through identification and designation of Special Protection Areas (SPAs).
  2. The Directives are given effect in Scottish Law by various regulations including, primarily:
  1. Hereafter, these are referred to as the Habitats Regulations.
  2. The Habitat Regulations require appropriate assessment of any plan or project which is likely to have a significant effect on a designated site, either individually or in combination with other plans or projects, in view of the site’s conservation objectives. Therefore, Marine Scotland are required to consider whether the Array is likely to have significant effects on the conservation objectives of the sites considered in the Habitats Regulations Appraisal (HRA). Where Likely Significant Effects (LSE, as defined by the Habitat Regulations) cannot be excluded at the screening stage, and in the absence of mitigation measures, an ‘Appropriate Assessment’ of the implication of the plan or project must be undertaken by the competent authority prior to granting consent for the proposed project.
  3. Appendix 4 provides further details of the LSE Screening and HRA process. A standalone LSE Screening Report has been prepared and submitted for consideration alongside this Scoping Report.

1.5.4. European Protected Species LicensingEuropean Protected Species Licensing

  1. EPS are animal and plant species listed in Annex IV of the Habitats Directive which are given protection under The Habitats Regulations 2017 (as amended). All cetacean species (whales, dolphins and porpoise) are EPSs. An EPS licence is required where an activity is likely to cause disturbance or injury, to ensure that the activity is undertaken legally.
  2. Subsea noise disturbance to marine mammals due to piling construction activities is one such activity which can be licenced under EPS licences. EPS licences are granted by NatureScot or the Scottish Ministers, depending on the species subject to the licence application. The granting of EPS licences is separate to the Section 36 and marine licence application process; however, it can be considered in parallel by Marine Scotland.

1.5.5. DecommissioningDecommissioning

  1. Statutory requirements in relation to the decommissioning of offshore renewable energy installations (OREIs) and their related electricity lines are set out in 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). Scottish Ministers may require a person who is responsible for these installations or lines in Scottish waters or in a Scottish part of a REZ to prepare (and carry out) a costed Decommissioning Programme for submission to and approval by Scottish Ministers under the terms of the Energy Act (Marine Scotland, 2018).
  2. Appendix 4 provides further details on decommissioning.

2. Project DescriptionProject Description

2.
Project DescriptionProject Description

2.1. IntroductionIntroduction

  1. This section of this Scoping Report outlines a description of the Array infrastructure and describes activities associated with the construction, operation and maintenance, and decommissioning phases of the Array. The design and components for the Array infrastructure are summarised here and have been developed based upon the latest design information and current understanding of the baseline environment from survey work and desktop studies.
  2. This Scoping Report covers the following infrastructure components:
  • wind turbine generators;
  • floating foundations and associated moorings and anchoring systems;
  • Offshore Substation Platforms (OSPs);
  • fixed bottom or floating foundations for the OSPs;
  • inter-array cables connecting the turbines to the OSPs;
  • interconnector cables connecting the OSPs to each other; and
  • scour protection and cable protection.
  1. The Proposed offshore export cable corridor(s) and Proposed onshore export cable(s) (including the onshore substation at the Proposed landfall location(s)) will be subject to a separate Environmental Impact Assessment (EIA) Scoping Report(s), EIA Report(s) and consent application(s) in the future.

2.2. Design Envelope ApproachDesign Envelope Approach

  1. The assessment of the Array will utilise the Project Design Envelope (PDE) approach (also known as the Rochdale Envelope approach), in accordance with current good practice, the “Rochdale Envelope Principle” [1], Scottish Government (2013) guidance, and guidance prepared by Marine Scotland and the Energy Consents Unit (Scottish Government, 2022l). The PDE concept will allow for sufficient flexibility in the final project design options, where the full details of a project are not known at the point of application submission.
  2. A “maximum design scenario” (MDS) approach is applied in the PDE concept, which considers a realistic range of project design parameters. For each impact pathway, the MDS will be developed from the PDE which will establish the parameters (or combination of parameters) that could result in the maximum effect (i.e. the maximum adverse scenario).
  3. The PDE approach could be used, for example, where several types of foundation mooring and anchoring systems are being considered. The assessment carried out in the Array EIA Report would be based upon the mooring and anchoring system known to have the greatest potential for impact (the realistic maximum adverse impact) to a particular receptor. In this example, the PDE for the mooring and anchoring system with the greatest potential for seabed disturbance would be the mooring and anchoring system with the largest footprint and the greatest number of wind turbines. If it is shown that no significant effect is anticipated after undertaking the impact               assessment for this scenario, it can then be predicted that any project parameters which are equal to or less than those assessed in the PDE will have the same level of, or less, environmental effects than the project parameters assessed. 
  4. The PDE approach will be applied throughout the EIA process to allow assessment of the potential impact of the Array to proceed, whilst still allowing for a level of flexibility where required for future project design decisions and advancements in technology.
  5. As the project progresses and a greater understanding of the Array is developed, the design envelope will be further refined up to design freeze. 
  6. Since the pre-Scoping workshops held by the Applicant in November 2022, some of the project design parameters presented in the workshop have changed. For clarity, Table 2.1   Open ▸ shows the parameters presented in the pre-Scoping workshops versus what is presented in this Scoping Report. The updated turbine parameters have been incorporated to account for the current commercially available technology and anticipated available technology during the latter stages of construction.

 

Table 2.1:
Changes to Maximum Design Envelope Since Pre-Scoping Workshops in November 2022

Table 2.1: Changes to Maximum Design Envelope Since Pre-Scoping Workshops in November 2022

 

2.3. Array SummaryArray Summary

  1. The PDE for the Array has been developed and refined through analysis of engineering, technical and environmental constraints and, therefore, provides an accurate summary of the Array EIA Report project description for which the Applicant is seeking necessary consent applications (Section 36 consent and marine licence(s)). Further development and refinement of the PDE will be undertaken throughout the EIA process as baseline data is collected and potential impacts are assessed. A 50-year consent life will be applied for.

2.3.1. ArrayArray

  1. The Array is located within the site boundary, which is located off the east coast of Scotland, approximately 80 km south-east of Aberdeen from the nearest point, and comprises an area of approximately 859 km2 (section 1,   Figure 1.1   Open ▸ ).
  2. In January 2022, as part of the ScotWind Leasing Round, the Applicant, was awarded an Option to Lease Agreement to develop Ossian, an offshore wind farm project within the E1 PO Area.
  3. The CES Option to Lease Agreement grants rights to the Applicant to carry out investigations within the site boundary, such as survey activities, to identify the potential design of the Array within the site boundary by understanding environmental and technical constraints.
  4. See section 1.2, Figure 1.1   Open ▸ for an illustration of the site boundary.

2.3.2. Water Depths and Seabed within the site boundaryWater Depths and Seabed within the site boundary

  1. A geophysical survey was conducted over the site boundary between March and July 2022 to collect geophysical and bathymetric data. The seafloor across the site boundary slopes gently downwards in an approximately north-west to south-east direction. The seafloor is generally flat, with mega-ripples and sand waves observed in the north-west of the site. Furrows were observed occasionally across the site boundary, more commonly in the west (Ocean Infinity, 2022a; Appendix 7).
  2. Across the site boundary, the maximum water depth was recorded at 88.7 m Lowest Astronomical Tide (LAT), and the shallowest area was recorded at 63.8 m LAT (Ocean Infinity, 2022a; Appendix 7).
  3. Seabed sediments within the site boundary are significantly dominated by deep circalittoral sand, with one area of limited extent comprised of deep circalittoral coarse sediment within the northern part of the site (EUSeaMap, 2021). The geophysical survey indicated that the seabed comprises mainly of sand, with areas of gravel in the west of the site boundary (Ocean Infinity, 2022a; Appendix 7).
  4. Further details of the bathymetry and seabed composition are presented within Appendix 5 and Appendix 7.

2.3.3. Array Infrastructure OverviewArray Infrastructure Overview

  1. The main components of the Array are expected to include:
  • up to 270 wind turbines (each comprising a tower section, nacelle, hub and three rotor blades) and associated floating support structures and foundations;
  • up to six OSPs with fixed foundations or associated floating support structures and foundations;
  • mooring and anchoring systems for each floating substructure, including anchors or piles for each mooring line;
  • a network of dynamic/static inter-array cabling linking the individual wind turbines to OSPs, and interconnector cables between OSPs (totalling approximately 1,515 km); and
  • ancillary elements including scour protection and clump weights.

2.3.4. Wind TurbinesWind Turbines

  1. The Array will comprise up to 270 wind turbines, however, the final number of wind turbines will be dependent on the capacity of individual wind turbines used, as well as the environmental and engineering survey results. If an increased rated output of wind turbine model is chosen when the final project design is developed, a reduced number of wind turbines may be installed.
  2. The maximum rotor blade diameter is expected to be up to 350 m, with a maximum blade tip height of up to 399 m above LAT. The lower blade tip height will be confirmed following ongoing engineering design work and taking into account preliminary environmental assessments to mitigate effects where appropriate, but will be greater than 22 m, in accordance with Marine Guidance Note (MGN) 654 (Maritime and Coastguard Agency (MCA), 2021). The hub height will be up to 224 m above LAT. The Applicant will develop and agree a scheme for wind turbine lighting and navigation marking with consultees post-consent decision. A schematic of a typical floating wind turbine is presented in Figure 2.1   Open ▸ .
  3. The layout of the wind turbines will be developed to effectively make use of the available wind resource and suitability of seabed conditions, as well as ensuring that the environmental effects and impacts on other marine users (e.g. fisheries and shipping routes) are kept to a minimum. Confirmation of the final layout of the wind turbines will occur at the final design stage (post-consent) and in consultation with relevant stakeholders.
  4. The design envelope for wind turbines is presented in Table 2.2   Open ▸ .

 

Table 2.2:
Maximum Design Envelope: Wind Turbines

Table 2.2: Maximum Design Envelope: Wind Turbines

Figure 2.1:
Schematic of a Typical Floating Wind Turbine

Figure 2.1: Schematic of a Typical Floating Wind Turbine

 

2.3.5. Wind Turbine Foundations and Support StructuresWind Turbine Foundations and Support Structures

  1. The Array will comprise wind turbines supported by floating substructures which require mooring and anchoring systems to maintain station. The substructures will be fixed to the seabed with up to nine mooring lines per foundation and anchored to the seabed via one or a combination of the anchoring types detailed in Table 2.4   Open ▸ .
  2. An overview of the typical floating substructure options is provided in Figure 2.2   Open ▸ . Each floating technology has varying dimensions as a result of the differing approach to meeting the unique engineering challenges associated with floating turbines, turbine sizes and project specific requirements. The final substructure design may look different those pictured but will follow the same design principles. The following floating substructure solutions are being considered:
  • Semi-submersible: A buoyancy stabilised platform which floats semi-submerged on the surface of the ocean whilst anchored to the seabed. The structure gains its stability through the buoyancy force associated with its large footprint (relative to the spar solution) and geometry, which ensures the wind loadings on the structure and turbine are countered/dampened by the equivalent buoyancy force on the opposite side of the structure.
  • Tension Leg Platform (TLP): A TLP is a semi-submerged buoyant structure, anchored to the seabed with tensioned mooring lines. The combination of the structure buoyancy and tension in the anchor and mooring system provides the platform stability. This system stability (as opposed to the stability coming from the floating structure itself) allows for a smaller and lighter floating structure.

Figure 2.2:
Floating Substructure Options for the Array

Figure 2.2: Floating Substructure Options for the Array

 

  1. Three mooring configurations are currently being considered, namely; catenary, semi taut and taut mooring lines, as presented in Table 2.4   Open ▸ . Semi taut mooring lines typically use mixed materials, for example, chain and synthetic rope, secured to the seabed with anchors and ancillary elements, as well as buoyancy modules which lift connections off the seabed. Taut mooring line systems use synthetic or steel wire rope lines fixed to the seabed which are under tension. Anchors for this type of mooring system must be capable of withstanding vertical lift, for example, Vertical Loading Anchors (VLAs) (ORE Catapult, 2021). Catenary mooring line systems typically comprise free hanging chains, secured to the seabed using anchors and ancillary elements and may be used where the other mooring solutions are not feasible. A schematic of the differing mooring systems is provided in Figure 2.3   Open ▸ .

Figure 2.3:
Schematic of Mooring System Options for Floating Wind Turbines

Figure 2.3: Schematic of Mooring System Options for Floating Wind Turbines

 

  1. Anchoring types considered include driven piles, and a number of different embedded anchor types, including suction piles, Drag Embedment Anchors (DEA) and VLA ( Table 2.4   Open ▸ ), with up to nine anchors required per foundation. A brief description of the various anchoring types that will be considered are presented in Table 2.3   Open ▸ . Images of the anchoring solutions are presented in Figure 2.4   Open ▸ .

 

Table 2.3:
Description of Anchoring Options Considered in the Maximum Design Envelope

Table 2.3: Description of Anchoring Options Considered in the Maximum Design Envelope

Figure 2.4:
Schematic of Anchoring Options Under Consideration as Part of the Proposed Mooring Configurations (Images Courtesy of Intermoor)

Figure 2.4: Schematic of Anchoring Options Under Consideration as Part of the Proposed Mooring Configurations (Images Courtesy of Intermoor)

 

  1. It should be noted that use of driven piles will only be undertaken where other solutions are not feasible, and only  a proportion of the foundations may be piled. There may be a mix of mooring and anchoring solutions used across the Array, which would reduce the number of driven piles which may be used. Geotechnical data acquisition and further studies will be undertaken to analyse ground conditions across the site boundary and inform mooring and anchoring solutions for floating turbine substructures. Further detail on foundation parameters and anchoring will be presented within the Project Description chapter of the Array EIA Report.
  2. The mooring and anchoring systems could be connected using a number of different connectors and ancillaries which alter the mooring system behaviour, such as:
  • Long Term Mooring (LTM) connectors (shackles or H-links);
  • clump weights;
  • buoys or buoyancy elements; and
  • tensioners.
  1. Clump weights are added to mooring lines to increase initial stiffness, which reduces dynamic loads and limits the mooring radius of the floating substructure. These are generally attached as a casing around the mooring line at the touchdown point on the seabed. A schematic of mooring line connectors and ancillaries is presented in Figure 2.5   Open ▸ .

Figure 2.5:
Schematic of Mooring Line Connectors and Ancillaries

Figure 2.5: Schematic of Mooring Line Connectors and Ancillaries

 

Table 2.4:
Maximum Design Envelope: Wind Turbine Foundations, Mooring Lines and Anchors

Table 2.4: Maximum Design Envelope: Wind Turbine Foundations, Mooring Lines and Anchors