Sectoral marine plan for offshore wind energy: strategic environmental assessment screening and scoping report

Sets out the proposed scope and level of detail for the assessment, as well as a description of the methodology.

2 Offshore wind energy and deep waters around Scotland

2.1 Background

2.1.1 Offshore wind accounts for a small but rapidly growing proportion of Scotland’s renewable energy portfolio. As of the end of 2017, Scotland had an installed operational capacity of 211 megawatts ( MW) (excluding Beatrice demonstration). As 2020 targets for renewable energy generation near [9] , and Scotland pursues more ambitious reductions in its greenhouse gas emissions, the focus has broadened to consider the potential to expand offshore wind energy into deep waters. The term ‘deep waters’ in this context typically refers to depths between 80-120m but could also include both shallower and deeper waters.

2.1.2 It is estimated that over 80% of Europe’s wind energy passes over waters deeper than 60m in depth, with a potential yield of 4000 gigawatts ( GW) [10] . Deep waters are particularly common in the Atlantic Ocean and areas of the North Sea [11] and it is estimated that the energy that could be derived from deep water turbines in the North Sea alone could exceed the EU’s electricity requirements four times over [12] . Scotland possesses approximately 25% of Europe’s total offshore wind resource [13] and as such, deep waters around Scotland may hold considerable potential for offshore wind energy development.

2.1.3 Scotland has an abundance of deep water resources located close to land [14] , particularly off the west coast where the shelf edge drops off fairly near to shore [15] . Sea depths off the west coast vary considerably but generally fall between 10-320m with an average depth of roughly 60m [16] . Waters off the east coast tend to be shallower and more uniform in depth, with a gradual downward slope towards the North Sea, but also include localised trenches and deeper areas of up to 200m depth such as the southeast Moray Firth [17] . Towards the northern reaches of the east coast, average depths tend to increase and past the Shetland Islands, depths of around 110m are found inshore of the shelf edge [18] .

2.1.4 Sea areas outside Scottish Territorial Waters (i.e. past 12 nautical miles [ nm]) are generally deeper than territorial waters, with large expanses of water at depths of 80-120m [19] . Such areas are particularly extensive in the Scottish portion of the North Sea. Additional areas of water of 120-300m depth are found in regions like the Fladen Ground in the North Sea [20] . The shelf edge west of Scotland presents very considerable challenges to development [21] and installation of developments in this area may benefit from more mature technology and experience from projects tested in other areas.

2.1.5 Waters past the territorial boundary have the potential to possess lower levels of constraint due to fewer competing environmental, commercial, and heritage interests. For example, at greater distances from shore, noise and visual impacts may be reduced [22] . In some instances, this can make such areas particularly suited to accommodating deep water wind energy technologies. In addition, wind resources tend to be stronger and less variable further offshore [23] where deep water is likely to be found, enabling turbines to be more consistently in operation and reducing turbulence.

2.2 Blue Seas Green Energy – A Sectoral Marine Plan for Offshore Wind Energy in Scottish Territorial Waters

2.2.1 In 2009, the Crown Estate Commissioners ( CEC) undertook the first stage of lease bidding and awarded Exclusivity Agreement awards (the first step towards securing a commercial lease) for 10 sites in Scottish Territorial Waters:

  • Solway Firth
  • Wigtown Bay
  • Kintyre
  • Islay
  • Argyll Array
  • Beatrice
  • Inch Cape
  • Neart na Gaoithe
  • Forth Array, and
  • Bell Rock

2.2.2 In response to the CEC leasing round and to support the sustainable delivery of the potential for offshore wind around Scotland, the Scottish Government made a commitment to produce a SEA of the potential for offshore wind development in Scottish Territorial Waters, to include the 10 site options. A draft Plan was developed to accompany the SEA Environment Report, and thereby ensure that those reviewing the assessment findings during statutory consultation were clear about the emerging proposals.

2.2.3 In addition to the short term sites identified by CEC, the Scottish Government commissioned a further constraint and opportunity mapping exercise in order to identify additional medium term options, within which there could be further potential for development beyond 2020. The marine spatial planning model, Marine Resource System ( MaRS), was used to identify options by mapping environmental and technical constraints as well as resource opportunities. This model identified 30 medium term options (areas of search). The 30 medium term options were then subject to environmental assessment, using the strategic environmental objectives developed with the Consultation Authorities. This resulted in 5 options being ruled out, including South West Option 2 ( SW2), due to its proximity to the Beaufort’s Dyke munitions dump. As a result, 25 medium term options (areas of search) were taken forward in the Sectoral Marine Plan.

2.2.4 Further to SEA, a HRA for the site and medium term options as well as a Socio-economic Assessment for the regional implications of the site options were commissioned. A consultation analysis report of all the consultation responses received for the SEA and Plan development process was produced.

2.2.5 In March 2011 Scottish Ministers, following consideration of the key findings from the SEA, HRA, Socio-economic Assessment and consultation analysis, decided that 6 short term sites would be progressed.

  • Islay
  • Argyll Array
  • Beatrice
  • Inch Cape
  • Neart na Gaoithe
  • Forth Array

2.2.6 In addition, Scottish Ministers’ recognised the 25 medium term options within the Plan as the starting point for the next strategic planning exercise to support offshore wind energy around Scotland

2.3 Draft Sectoral Marine Plan for Offshore Wind Energy in Scottish Waters

2.3.1 As per its commitment to a two-year review, Blue Seas – Green Energy was reviewed in 2013 alongside the Sectoral Marine Plans for Wave and Tidal Renewables [24] . The review included a re-evaluation of the previous selection of medium term development areas and broadened the geographic scope of consideration to include non-territorial waters (i.e. out to 200 nm). The latter involved identifying both additional medium term areas of search as well as areas of deeper water that could become suitable as turbine structure technologies progress and become commercially deliverable at greater depths.

2.3.2 To help refine the potential areas of search, Regional Locational Guidance ( RLG) was prepared which gave consideration to detailed environmental, technical, socio-economic and planning issues in relation to the offshore renewable energy regions of Scotland [25] . This led to the development of an Initial Plan Framework comprised of draft Plan Options which are intended to guide developers towards suitable areas when planning projects to go through a marine licensing process [26] . This Initial Plan Framework was subject to an iterative series of assessments including SEA, an HRA, and a socio-economic assessment, which informed a public consultation on the Draft Plan for Offshore Wind Energy 2013. This Plan contained 10 draft Plan Options which were subsequently reflected in the publication of Scotland’s National Marine Plan in 2015.

2.3.3 However, due to the challenges faced by the offshore wind industry during this period, resulting from the change in subsidy mechanism from ROCs (renewables obligations certificates) to Contract for Difference, the Draft Plan was never formally adopted by Scottish Ministers’.

2.4 Draft Sectoral Marine Plan for Offshore Wind Energy - 2019

2.4.1 As a result of significant cost reductions in the offshore wind sector in recent years, together with the emergence of floating technology for offshore wind sub-structures, Crown Estate Scotland announced their intention to run a new leasing round for commercial scale offshore wind technologies in Scottish Waters. As a result, Marine Scotland, as planning authority for Scotland’s Seas, will undertake a new strategic planning exercise to inform the spatial development of any future leasing round.

2.4.2 The forthcoming Draft Plan will look to establish similar areas of search suitable for wind energy generation in Scotland. Such areas of search may include deep water sites. The previous Plan Options presently remain as live drafts and will be reviewed within the context of the development of the 2019 Draft Plan. The timeline and process of identifying areas for offshore wind energy development in Scottish waters to date, including where the present Plan options feature in relation to previous work, is illustrated by Figure 1. Figure 2 depicts the new proposed areas of search.

Figure 1 Timeline and process of identifying sites for offshore wind energy development in Scottish waters to date

Figure 1 Timeline and process of identifying sites for offshore wind energy development in Scottish waters to date

Figure 2. Proposed Areas of Search

Figure 2. Proposed Areas of Search

2.5 Other Offshore Wind Planning/Developments in Scotland

2.5.1 In addition to the strategic planning exercises administered by Scottish Ministers’, two additional development zones in Scottish waters were identified by Crown Estate Round 3 in 2010 and have received consent: Moray Firth Eastern Development [27] and Seagreen Alpha and Bravo [28] . The Moray Firth site has since progressed further and obtained a contract to build.

2.5.2 Furthermore, a number of demonstration projects have been developed or are in the process of development within Scottish Waters. The first of these, Beatrice Demonstration, served as an industry trial of deep water bottom-fixed foundations [29] . The Levenmouth Demonstration Turbine [30] provided research opportunities to help drive cost reduction in offshore wind, whilst the Forthwind project [31] will allow 2B Energy to test turbine technology. In addition, Dounreay Trì [32] , Hywind Scotland Pilot Park (later opened as Hywind Scotland), and Kincardine [33] were designated as Scottish Floating Demonstrations to further test and refine floating technologies. Also, it is understood that the European Offshore Wind Deployment Centre will be an offshore deployment centre allowing offshore wind developers and supply chain companies to demonstrate technologies in a representative environment before commercial deployment [34] .

2.5.3 One of the initial demonstration offshore wind projects, Robin Rigg [35] , was developed in Solway Firth and has been operational for around a decade. Table 1 provides a list of all consented offshore wind installations in Scotland.

2.5.4 The sites and options that have come forward from these processes will be considered, where necessary, for the purpose of cumulative assessments within the forthcoming planning process.

Table 1. Consented offshore wind installations in Scottish waters

Site Location Round or Development Category Project Capacity Status
European Offshore Wind Deployment Centre Scotland, Grampion – North Sea Demonstration 100 MW Consented
Beatrice Scotland, Highland – North Sea Scottish Territorial Waters 588 MW Consented
Beatrice Demonstration Scotland, Highland – North Sea Deepwater Demonstration 10 MW Operational; decommissioning announced in May 2017
Dounreay Trì Scotland, Highland – Scottish Continental Shelf (Fair Isle) Scottish Floating Demonstration 12 MW Consented
Seagreen Alpha and Bravo Scotland, Tayside – North Sea Crown Estate Round 3, DECC SEA 2 1050 MW Consented
Hywind Scotland Scotland, Grampion – North Sea Scottish Floating Demonstration 30 MW Operational
Inch Cape Scotland, Tayside – North Sea Scottish Territorial Waters 784 MW Consented
Kincardine Offshore Wind Farm Scotland, Aberdeenshire – North Sea Scottish Floating Demonstration 50 MW Consented
Moray Firth Eastern Development Scotland, Highland – North Sea Crown Estate Round 3, DECC SEA 2 950 MW Consented; contract to build
Neart na Gaoithe Scotland, Lothian - North Sea Scottish Territorial Waters 448 MW Consented
Robin Rigg Scotland, Dumfries & Galloway – Irish Sea Crown Estate Round 1 174 MW Operational
Forthwind Scotland, Fife – North Sea Demonstration 18 MW Consented
Levenmouth Demonstration Turbine Scotland, Fife – North Sea Demonstration 7 MW Operational


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