Borssele Wind Farm Zone

Transcription

1 Borssele Wind Farm Zone Project & Site Description >> Sustainable. Agricultural. Innovative. International.

2 Foreword The Netherlands wants sustainable, reliable and available energy that is affordable for everyone. A transition to sustainable energy is of great importance. Not only because of the climate and the declining availability of fossil fuels, but also to be less dependent on international energy suppliers. In the National Energy Agreement, a goal of 16% sustainable energy in 2023 was agreed on with 40 parties. We need all the different sustainable energy sources for this, including wind energy. In September 2014, the Dutch government designated three areas where wind farms can be developed the coming years. These areas are located off the coast of North- and South Holland and the province of Zealand near Borssele. The first area that will be developed is the Borssele zone, outside the 12-mile zone off the coast of Zealand and designated in Because Borssele is relatively near shore, the costs of development and operation of the wind farm will be relatively low. It is also an area with relatively little other interests. For example, there are no oil and gas platforms that have to be taken into account. Before development, the plans will be presented and discussed with stakeholders. In consultation with the wind energy sector, a new system was designed for the deployment of offshore wind energy. The government is responsible for all conditions like permits and the connection to the grid. This approach contributes to efficient use of space, cost reduction and an acceleration of the deployment of offshore wind energy. Companies that want to develop a wind farm can register for one of the selected areas. The company with the best and cheapest plan obtains the permit and grant to develop the park. This Project & Site Description provides an overview of the current progress towards the first step in the process to increase from 1,000 to 4,500 MW offshore wind power: the tendering of wind farm sites Borssele I and II, with a total capacity of 700 MW. In the months towards the tender, the Project & Site Description will be updated accordingly.

3 Table of Contents 1 Objectives & Reading Guide Objectives Reading Guide 5 2 General introduction & Legal Framework Offshore wind farms in the Netherlands The roadmap towards 4,500 MW offshore wind power The Offshore Wind Energy Law Wind farm zones The 2015 Tender: Borssele wind farm zone 10 3 Process & Quality Assurance Process Project Management Procurement Quality Assurance 13 4 Borssele Wind Farm Zone Site Description General Description Layout & coordinates Exclusion Zones Specific characteristics of the wind farm zone Bandwidth of design characteristics Environmental Impact Assessment Procedure Existing infrastructure Nearby Belgian wind farms Applicable laws for activities in the Borssele wind farm zone 23 5 Site data Geological Desk Study Morphodynamical Desk Study Archaeological assessment Unexploded Ordnance (UXO) assessment Metocean Study Assessment Wind Measurement Campaign options 34 3

4 6. Electrical Infrastructure General introduction Technical Concept Locations TenneT platforms Voltage level for connection (66kV) Commercial conditions 37 7 Next Steps Project Planning Deliverables and updates 39 8 Applicable documents 41 4

5 1 Objectives & Reading Guide 1.1 Objectives The Project & Site Description (PSD) aims at facilitating any party that has an interest in the (planned) SDE+ subsidy tender for the Borssele wind farm zone (BFWZ) in the Netherlands. This document summarizes: The process towards the SDE+ tender and the legal framework. A description of the site, the surroundings and a selection of constraints and (technical) requirements that are deemed to be most relevant for development of the Borssele area. All data collected by the Netherlands Enterprise Agency (Rijksdienst voor Ondernemend Nederland; RVO.nl) regarding the physical environment of the Borssele area. This document is developed for information purposes only and is not intended to replace any legal or formally communicated rules, regulation or requirements. 1.2 Reading Guide The Project & Site Description is a snapshot overview of the project progress and aims to provide all relevant information to interested parties as soon as possible. Therefore, multiple revisions of the Project & Site Description are planned. This revision of the Project & Site Description covers the following aspects in the different chapters: 1. Chapter 1 Objectives & Reading Guide (this chapter) 2. Chapter 2 (General Introduction & Legal Framework) provides a general introduction in the history and the current state of the Dutch offshore wind farms. Moreover, the process towards the large scale rollout of offshore wind is described, including the Offshore Wind Energy Law and wind farm site decisions. 3. Chapter 3 (Process & Quality Assurance) contains information on the process towards optimal site information for tender applicants. 4. Chapter 4 (BWFZ - Site Description) contains general information on the Borssele wind farm zone, the location, surroundings, its bathymetry, exclusion zones and the design bandwidths of offshore wind turbines allowed in the wind farm zone 5. Chapter 5 (Site Data) is a summary of all the studies that have currently been performed on the Borssele wind farm zone, and addresses the following aspects: Soil characteristics based on geological desk study Morphodynamical desk study Archaeological assessment; UXO characteristics based on UXO desk study Metocean characteristics, based on the metocean desk study Assessment Wind Measurement Campain options 6. Chapter 6 (Electrical Infrastructure) shows the planned location and characteristics of TenneT offshore High Voltage platforms 7. Chapter 7 (Next Steps) is an overview of the process towards the tendering of Borssele wind farm sites I and II in 2015 and the expected updates to the site data to be included in the next revisions of the Project & Site Description 8. Chapter 8 contains a list of Applicable Documents 5

6 2 General introduction & Legal Framework 2.1 Offshore wind farms in the Netherlands The existing offshore wind farms and those under construction in the Netherlands have a capacity approximately 1,000 MW. The first two wind farms built in the North Sea off the coast of the Netherlands are the offshore Wind Farm Egmond aan Zee (OWEZ, 2006) and the Princess Amalia Wind Farm (2008). The Egmond aan Zee Offshore Wind Farm lies km off the coast and exists of 36 Vestas 3 MW turbines, is owned by Noordzeewind, a joint venture between utility company NUON and oil company Shell. Utility company Eneco owns the Princess Amalia Wind Farm, located outside the 12-mile zone, 23 km off the coast. It exists of 60 Vestas 2 MW turbines. Two projects are currently (2014) under construction: Wind farm Luchterduinen and the Gemini wind farm. Wind farm Luchterduinen is owned by Eneco and Mitsubishi Corporation and exists of 43 Vestas 3 MW turbines located 23 km off the coast. It is expected that this wind farm will be fully operational in The Gemini wind farm will be constructed with 150 Siemens 4 MW turbines on the twin locations Buitengaats and Zee-Energie, 85 km off the coast. Gemini is owned by Northland Power, Siemens, Van Oord and HVC. This wind farm is expected to be fully operational in The roadmap towards 4,500 MW offshore wind power In 2013 more than forty organisations laid the basis for a robust, future-proof energy and climate policy for the Netherlands in the Energy Agreement for Sustainable Growth (Energieakkoord voor Duurzame Groei) [1]. An important part of this agreement is scaling up offshore wind power. In September 2014 the Minister of Economic Affairs presented a road map to the parliament [2] enabling the Government to achieve this expansion of offshore wind in accordance with the time line agreed upon in the Energy Agreement. The road map foresees an annual tendering of 700 MW in the period , with the requirement that the cost of offshore wind power will decrease by 40% in the coming years. Wind farms will become operational within four years after a decision on funding and can use the state-of-the-art technology available at that time. The legal bases of this road map will be a new Offshore Wind Energy Law. 2.3 The Offshore Wind Energy Law As mentioned before, the Dutch government requires a cost reduction of 40% when providing future offshore wind grants. As part of this strategy, they developed a systematic framework in which the Dutch government creates designated offshore wind areas with different sites that are tendered. These sites already have a permit, an exploitation subsidy and a grid connection to the main land. Moreover, most geological and meteorological surveys have already been performed. This procedure is expected to be much cheaper than the previously tendered wind farms, in which developers were required to apply for a permit for a certain part of the North Sea and perform desk studies and surveys themselves. Finally, when large amounts of costs already were incurred, they could apply for a subsidy. 6

7 This new approach is presented in the Offshore Wind Energy Law (Wet Windenergie op Zee), which is expected to enter into force at the 1st of July The bill was sent to the parliament on October 17th The new system for offshore wind energy introduced with this law was designed in consultation with the sector. It contributes to a higher efficiency in the use of space, cost reduction and it accelerates the deployment of offshore wind energy. The system consists of five distinct aspects, as described in the paragraphs below Wind farms are only allowed in designated wind farm zones Under the National Water Plan [3], wind farm zones have been designated as shown in Figure 1. Only on sites within these zones, the construction of wind farms will be allowed. Any location outside these wind farm zones will not be consented. Figure 1 Designated wind farm zones in the Netherlands continental shelf: A: IJmuiden Ver, B: Borssele (off the Zealand coast), C: Off the Holland Coast, D: North of the Dutch Wadden Isles. Current wind farms are shown in red/brown. 7

8 2.3.2 Wind farm sites consented by government ( Kavelbesluiten ) In these wind farm zones the government decides on sites where wind farms can be constructed. Each zone can contain several sites. The Ministries of Economic Affairs and of Infrastructure and the Environment will decide on the so-called wind farm site decisions ( kavelbesluiten ). A wind farm site decision is the necessary consent required to build a wind farm and specifies the location for the wind farm and the conditions under which it may be constructed and operated. These conditions will provide flexibility for the design of the wind farm. This gives commercial parties the best opportunities for choosing the best technical option within the natural and environmental framework and realise their project at the lowest possible costs. Wind farm site decisions are subject to an environmental impact assessment (EIA), which will be commissioned by the Ministries of Economic Affairs and of Infrastructure and the Environment Government provides site data The Government investigates the physical environment of the wind farm site: the soil- wind- and water conditions. This site data will be made public and provides commercial parties information for their FEED studies and to make competitive bids in the tendering procedure for the grant possibilities. The Netherlands Enterprise Agency (RVO.nl) will make the site data available. This site data includes: Geological, morphodynamical and geomorphological data Archaeological and UXO analysis Metocean data Wind resource assessment Geophysical and geotechnical data (based on surveys) Wind data (for Borssele based on in situ floating LiDAR campaign) TSO TenneT realises grid connection To create economies of scale the national electricity Transmission System Operator TenneT will construct five standardised platforms with a capacity of 700 MW each in the wind farm zones. They will each be connected to the national grid with two 220kV export cables. As soon as a 380kV subsea cable is available, this will be used to reduce the amount of required cables. Connecting wind turbines directly to the TenneT platform implies no need for an OWF platform investment Grant tendering Grants for the wind farm sites will be awarded through a dedicated call for tender under the Stimulation of Sustainable Energy Production (SDE+, Stimulering Duurzame Energieproductie). Under this scheme, producers receive financial compensation for the electricity they generate for a fixed number of years. The lowest bidder will be awarded. The bid must be equal or lower than the maximum amount (in /kwh) set for the specific wind farm site. The lowest bidder will be rewarded with both the grant and the consent to build and operate a wind farm according to the wind farm site decisions. 8

9 2.4 Wind farm zones The Government has decided that three offshore wind farm zones will be used for the deployment of the 3,500 MW new offshore wind power as agreed upon in the Energy Agreement: Borssele (1,400 MW), South Holland coast wind farm zone (1,400 MW) and North Holland coast wind farm zone (700 MW). Figure 2 shows a schematic representation of the deployment. Wind farms 700 MW Wind farms in operation or under construction Designated areas Proposed areas Figure 2 Tender planning for the Dutch Offshore Wind Rollout 9

10 The tenders to select parties for realising the offshore wind farms will be done according to the schedule below. Year Power Wind farm zone MW Borssele wind farm zone MW Borssele wind farm zone MW South Holland coast wind farm zone MW South Holland coast wind farm zone MW North Holland coast wind farm zone 2.5 The 2015 Tender: Borssele wind farm zone In 2015 and 2016, the Borssele wind farm zone will be tendered under the Dutch Offshore Wind Energy Law. This Project & Site Description provides information on the project, the process and site data for the first tender which is planned to open in December 2015 and comprises two wind farm sites with a total capacity of 700 MW. 10

11 3 Process & Quality Assurance 3.1 Process The Dutch Ministries of Economic Affairs and of Infrastructure and the Environment are responsible for the execution of the Offshore Wind Energy Law. One of the key aspects is the preparation of a wind farm site decision ( Kavelbesluit in Dutch) for the tendered locations, in this case the Borssele wind farm zone (BWFZ). The Netherlands Enterprise Agency (RVO.nl) is responsible for collecting all relevant site information that potential bidders require for preparing their bid when competing in the SDE+ tenders for the BWFZ. The site information package should be of sufficient detail and quality. For this, RVO.nl has sought guidance and information by consulting different sources. The organisation in Denmark responsible for organising the Danish offshore wind tenders (Energinet.DK) has shared their lessons learned and shown RVO.nl how these projects are managed in Denmark. Further, RVO.nl, the Ministry of Economic Affairs, Rijkswaterstaat (part of the Ministry of Infrastructure and the Environment) and TenneT organised several workshops on various subjects with market parties, who were broadly invited by the Dutch Wind Energy Association (NWEA) and other communication channels. RVO.nl has selected BLIX Consultancy as the primary consultant assisting RVO.nl in managing the process. BLIX is one of the leading offshore wind consultants in the Netherlands and is specialised in project management of large (offshore) wind energy projects. The consultants of BLIX have been involved in several offshore wind farm projects in the Netherlands, Germany and Belgium and were, amongst others, responsible for managing and contracting site studies and investigations for these projects. 3.2 Project Management The first step in the process was the creation of the Work Breakdown Structure (WBS) and a planning for the project. On the basis of the WBS and the planning, the interfaces with other work streams in the project were managed. The WBS of the project mainly consisted of three blocks: 1. Desk studies 2. Site selection / prioritisation 3. Detailed site investigations These activities are interrelated with the other work streams being; 1. Defining the legal framework for Offshore Wind Energy projects by the Ministries of Economic Affairs and of Infrastructure and the Environment, 2. The spatial planning and sea use as managed by the Ministry of Infrastructure and the Environment and, 3. The realisation of the offshore grid under the responsibility of TenneT. Through weekly project meetings between the parties involved these processes were aligned and information was exchanged. The overall planning and the WBS were shared with market parties in a meeting organised by RVO.nl and NWEA in order to identify possible omissions and to obtain input on objectives and content of the site studies and investigations that were put on the market. 11

12 3.3 Procurement Limited tenders The procurement of the different studies was carried out in compliance with the applicable procurement procedures within RVO.nl. The desks studies have been procured through a limited tender where, for each study, at least two expert parties were invited to submit their proposal. The proposals have been selected on the basis of determining the economic most advantageous offer. This means that the proposals have been assessed and scored (by at least three assessors) on several aspects such as: track record, quality of the proposal and the price offered. Studies that have been procured through a limited tender are the following: 1. Geological desk study 2. UXO assessment 3. Archaeological assessment 4. Morphodynamical desk study 5. Metocean desk study Public tenders The site investigations which exceeded the expected budget for a limited tender were procured through a public European tender. These investigations included the investigations that are actually carried out offshore: 1. Geophysical soil investigations 2. Geotechnical soil investigations 3. Wind Measurements The offshore site investigations that need to be carried out have not yet started since the procurement process is still in progress. It is expected that these investigations will start in the first quarter of

13 3.4 Quality Assurance RVO.nl and BLIX maintained a rigorous quality assurance procedure to provide accurate and usable studies. First, the scope of the different studies was determined using the following steps: 1. RVO.nl and BLIX determined the preliminary scope of the different studies; 2. Where applicable, input was provided on these scope descriptions by internal experts of other governmental departments, agencies or external experts; 3. At market consultation sessions, the scope descriptions were discussed with market parties and input on completeness was provided by the attendees of these workshops. In the case of studies where the results will become part of the design basis of the developer, the certifying authority DNV-GL was contracted to confirm the completeness of the scope. After the tender, during the execution of the work by the specific executor, quality assurance was performed as follows: 1. The project team and experts of other ministries reviewed several drafts of the report, provided feedback and assured that the execution of the scope was in compliance with the scope description; 2. The draft report was reviewed by the independent internal and external experts; 3. The certifying authority (DNV-GL) reviewed the report and provided a statement of compliance (Metocean, Morphodynamics) to assure the results were acquired in compliance with the DNV-OSJ101 and other applicable industry standards. These statements of compliance are added to the report if applicable. Internal experts that have provided input in the process include: 1. The Cultural Heritage Agency (Archaeological desk study) 2. The Ministry of Infrastructure and the Environment (Morphodynamical desk study) External experts that have provided input in the process include: 1. Windsupport Ltd (Geotechnical site investigations) 2. Reynolds International Ltd (Geophysical site investigations) 13

14 4 Borssele Wind Farm Zone Site Description 4.1 General Description The Borssele wind farm zone (BWFZ) is located at the southern border of the Netherlands Exclusive Economic Zone (EEZ); 0.5 km from the Belgium EEZ. The zone borders on a sand extraction area in the southeast and a piloting area in the east. Anchoring areas and a shipping lane are located at the north side of the zone. The Belgian dedicated offshore wind zone is located directly to the southwest. Figure 3 shows the location of the Borssele wind farm zone, the Belgian Zone and the location of cables and pipelines. Figure 3 The Borssele wind farm zone and surrounding areas 4.2 Layout & coordinates The wind farm zone of approximately 344 km2 is sub-divided into four wind farm sites. In total, 1,400 MW offshore wind is planned in the zone, roughly 350 MW per site. Figure 4 and Figure 5 show the general coordinates of the Borssele wind farm zone and its different sites. In the attached memo [5] all coordinates of different sites and investigation zones of the wind farm zone are shown. Site I and II (total capacity 700 MW) are expected to be tendered by the end of 2015; Wind Farm Site III & IV will follow in

15 Borssele Wind Farm Zone Site - zone Site IV Site I Sources: Copyright Service for the Kadaster and the public registers, Apeldoorn Copyright Dienst Landelijk Gebied No rights can be derived from this map Site III Site II 12 Nautical mile zone A4 - scale1: ,5 1 2 NM km Legend Wind Farm Belgium Status (situation 2014) Application Licensed In operation Nautical 12 mile TenneT platform Alpha TenneT export cables Territorial sea Exclusive Economic Zone of the Netherlands Cables safety zone 750m Pipelines safety zone 500m TenneT Cable Safety Zone 500m Overlap piloting zone incl 500m safety zone Designated Wind Farm Zone Designated Wind Farm Zone + 500m Location helicopter approach routes not yet included This geographical information is based on the data available on October 28th Updates will be made available on Consultant: date: revisie: mapnr: RH Figure 4 The 4 sites within the Borssle wind farm zone including the location of the TenneT platform Alpha 15

16 Site II is an undivided parcel of around 68 km². Site I of around 63 km² is subdivided into 4 parcels as a result of pipelines and cables in the areas. All square kilometres mentioned in this paragraph are exclusive of safety zones, export cables, TenneT platform and potential helicopter flight paths. Geographical coordinates (ETRS89) UTM (ETRS89, zone 31) Point Nr Degrees N Degrees E Easting Northing 1 51, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,30 Figure 5 The 4 sites of the Borssele wind farm zone and their coordinates. 16

17 4.3 Exclusion Zones The Dutch-Belgian border is located immediately south of the BWFZ; the Belgian dedicated offshore wind zone is situated on the direct opposite of this border. Paragraph 4.8 provides an overview of the Belgian Wind Farms and their characteristics. To the east, the BWFZ is bordered by the 12-mile zone and the pilotage zone Steenbank (the blue area in Figure 4). Moreover, several pipelines and telecommunication cables are located within the zone, as shown in paragraph 4.7. These pipelines and cables, together with their safety zones (500 metres for pipelines and 750 metres for cables), are excluded from the different parcels. The part of the wind farm zone, which overlaps with the pilotage zone and an additional safety zone of 500 metres is excluded for wind farms as well. A detailed overview of the safety zones around cables and pipelines can be found in the Integrated North Sea Management Plan 2015 [6]. Table 1 provides an overview of the preliminary safety zones to be respected around wind farms: Table 1 Required safety zones around wind farms Function Explanatory Single width safety zone High voltage cables and pipelines Contain high levels of metal, hence relatively easy to detect. Damages and related repairs exceptional. 500 m Telecom cables Relatively small, hence hard to detect and vulnerable for damages, repairs are likely to occur. Repair vessels need extra space for maneuverer. 750 m Helicopter flight paths Apart from avoiding collisions, helicopters are affected by the wind turbine wakes. Dependent on rotor diameter. Sand extraction areas Lowers the seabed, which could affect the sand coverage of cables or scour protection around foundations. 500 m Shipping lanes Intention is to allow marine traffic up to 24 meters of the wind farm zone. Decision Q in National Water Plan m Please note that the distances to respect are preliminary. In some cases, i.e. the distance to shipping lanes, it is not clear yet if this should be measured from the tower or from the tower plus rotor blade. In most cases the proximity agreement between de cable or pipeline owner and the wind farm operator foresees in switching off the wind turbines closest to the cable or pipeline during repair activities. 17

18 4.4 Specific characteristics of the wind farm zone The Borssele wind farm zone has the following general characteristics, as show in Table 2. Table 2 Characteristics of the Borssele wind farm zone Water depth 16 to 38 m Distance from shore From 22.2 km (12 nautical miles ) Surface area (incl. safety zones) 344 km2 Surface area (excl. safety zones) 234 km2 Surface of Wind Farm Site I 44 km2 (plots of 24, 16, 1 and 3km2) Wind Turbine Density site I 8 MW/km2 Surface of Wind Farm Site II 68 km2 Wind Turbine Density site II 5,2 MW/km2 The basic bathymetry of the BWFZ is shown in Figure 6. More detailed bathymetry and morphodynamical information of the zone are provided in the next chapters. Figure 6 Bathymetry of the Borssele wind farm zone in

19 4.5 Bandwidth of design characteristics As indicated before, both the permitting and EIA-procedures have already started. By allocating plots with different possibilities for wind turbine arrangements and -types and methods for foundations, within a certain range, a flexible arrangement of the plots is possible. The developer has the freedom to make an optimal design for the wind farm in terms of costs and energy yield. By assuming a worst-case scenario with regard to the possible impacts, all the different configurations that are possible in the plots are investigated in the EIA. Table 3 shows the bandwidth for different design parameters that have been chosen in the draft Memorandum Scope and Level of Detail, currently under investigation in the EIA. Table 3 Bandwidth of design characteristics for the Borssele wind farm Subject Power individual wind turbines Tip height individual wind turbines Tip lowness individual wind turbines Rotor diameter individual wind turbines Spacing between wind turbines Bandwidth 3 10 MW meter meter meter 4x rotor diameter Number of blades per wind turbine 2 3 Type of substructures Type of foundations Installing piles In the case of hammering: hammer energy related to turbine type / pile Monopile, jacket, tripile, tripod, gravity based structure (Mono)piles, suction buckets, gravity based structures Vibratory, hammering, boring, suction 1,000 3,000 kj, depending on soil conditions and diameter foundation In the case of hammering: diameter pile(s) and number of piles per turbine: In the case of a foundation without hammering: dimensions at seabed: Electrical infrastructure, voltage level infield cables Jacket Monopile Tripod Gravity Based Suction Bucket 33kV or 66kV 4 piles of 1,5 3,5 meter 1 pile of 4-10 meter 3 piles of 2-4 meter 40 x 40 meter Diameter bucket: t.b.d. If environmental requirements cannot be fulfilled, a limit of the design options on the plots will be put in place; the bandwidth in the table will be (slightly) reduced in the final wind farm site decision where appropriate. Therefore the bandwidth presented here is not final. Developers interested in the Borssele tender should keep their designs within the abovementioned characteristics in order to stay within bandwidth of the wind farm site decisions. 19

20 4.6 Environmental Impact Assessment Procedure The procedure for an Environmental Impact Assessment (EIA) is prescribed in national and European legislation in case of activities with potentially significant environmental effects. The Environmental Impact Assessment examines the first two sites that will be tendered in 2015 and The EIA discusses the environmental impacts associated with the establishment of wind farms on these sites. The impacts are compared with the applicable environmental requirements, whereby it is assessed if they meet these requirements. The level of detail of the EIA will be in such a way that prior to the construction of the two wind farms on the basis of the site decisions, an extra EIA is not necessary. The EIA has been prepared and is currently available for comments. Moreover, the Netherlands Commission for environmental assessment has already positively reviewed the draft EIA. Based on the comments from the market and environmental organisations, the EIA will be finalised. 20

21 4.7 Existing infrastructure Several operational cables and pipelines cross the wind farm zone. Furthermore, several abandoned cables/ pipelines run through the Borssele area. Figure 7 shows the Borssele wind farm zone and infrastructure crossing the zone. Name Type Status TAT14 Telecommunications Exclusion Zone Franpipe Natural Gas-pipeline Exclusion Zone SeaMeWe 3 Telecommunications Feasibility of relocating cable Farland North Telecommunications Exclusion Zone Zeepipe Natural Gas-pipeline Exclusion Zone Figure 7 Cables and pipelines in the Borssele wind farm zone Currently, talks between RVO.nl and the operators of cables concerning possibilities for relocation of cables, crossing- and or proximity arrangements are underway. 21

22 4.8 Nearby Belgian wind farms Mermaid Belwind Seastar Northwester 2 Northwind Rentel C-Power Norther Name Hubheight [m] Rotor diameter [m] Assumed individual capacity [MW] Nr Total capacity [MW] Status Belwind I Fully commissioned Belwind II 165 Under development BW-Pilot Under construction Northwind Fully commissioned C-Power I Fully commissioned C-Power II , Fully commissioned C-Power III , ,7 Fully commissioned Rentel Consent received Seastar Consent received Norther Consent received Mermaid Consent received Northwester Consent received Figure 8 The location of the Belgian Offshore Wind Farms directly southward of the BWFZ Several Belgian wind farms are operational or under construction directly south of the Dutch-Belgian Border. Figure 8 shows a map of the Belgian dedicated offshore wind zone, the different wind farms in the zone and their status and characteristics. 22

23 4.9 Applicable laws for activities in the Borssele wind farm zone In the Exclusive Economic Zone (EEZ) outside the Dutch territorial sea (the 12-mile zone), only the laws declared in force for that zone by the legislator are applicable. These include the Water Act, the Mining Act and the Earth Removal Act. The Flora and Fauna Act and the Nature Conservation Act will eventually also enter into force within the EEZ. 23

24 5 Site data 5.1 Geological Desk Study Introduction The Geological Desk Study provides insight into the soil conditions at the Borssele wind farm zone, more specifically: Insight in the geological stratification of the Borssele wind farm zone on the basis of sufficient and relevant cross sections of the site. Information on the uniformity of the geological stratification and the presence of possible disturbances in the uniformity of layers as a result of e.g. ancient streambeds, boulders, etc. Description of the soil characteristics of the geological layers and possible disturbances. Description of the possible impact (design & installation) of the different geological layers on generic wind turbine foundation concepts Supplier A consortium of CRUX, edigeo and GisSense performed the geological desk study [7]. CRUX has experience in soil research for both onshore as well as offshore projects, providing soil stability analysis during the lifting of the Costa Concordia and geotechnical research on the consequences of gas production in Groningen Results Because of limited commercial interest in the area, both geological and geotechnical data in the Borssele area are scarce. For example, only few borings with a depth of 1-5 meters are available and none are available with a longer depth. The water depth of the zone ranges from 10 to 40 meters, with dispersed sand banks of up to 20 meters high. The subsurface consists of Pleistocene (sand) and Holocene (sand, clay, peat) formations in the upper 10 to 30 meters, on top of stiff clay Tertiary deposits, as shown in Figure 9. Figure 9 Top of Tertiary (left) and Pleistocene (right) 24

25 5.1.4 Conclusion From a geological perspective, the soil conditions of Borssele are suitable for offshore wind developments using all common installation techniques and foundation types. However, based upon data currently available, it is impossible to identify areas with more optimal or less optimal soil conditions within the site. 5.2 Morphodynamical Desk Study Introduction This study provides insight in the sea bed dynamics at the Borssele wind farm zone and consists of the following elements: 1. Improve the understanding of the seabed morphology at the Borssele wind farm zone. 2. Improve the understanding of the seabed morphodynamics at the Borssele wind farm zone over the lifetime of a wind farm (25 years). 3. Define design reference seabed levels at the Borssele wind farm zone over the lifetime of a wind farm (25 years). 4. Input for soil investigations still to be carried out Supplier Deltares has performed the morphodynamical desk study [8]. The institute has an extensive track record in offshore wind, with most studies related to topics such as scour prediction and protection, metocean conditions, wave loads, cable burial depth and morphodynamics. Deltares has previously performed similar studies for other offshore wind farms, such as Princess Amalia wind park, Butendiek, Luchterduinen Nordergründe and Belwind. The Belwind site is adjacent to the Borssele site, on the Belgian side of the border. Therefore, Deltares also has in depth knowledge of the morphology of this specific part of the North Sea. DNV-GL has been contracted to assess the methodology and the results of the study. This process has taken place with a positive outcome and will be confirmed by a statement of compliance which is expected soon Results High quality bathymetry data from 2010 were compared with combined data of around 2000 in order to gain insight into the soil morphology of the system. The site has highly dynamic soil morphology, consisting of static, shore-parallel sand banks overlaid with dynamic shore-perpendicular sand waves. Within the area, opposing migration directions were found, as shown in Figure

26 Figure 10 Morphodynamics: Sand dune movement in the Borssele wind farm zone The shore perpendicular sand waves have a typical average length of 230 meters, height of 4 meters and migration speeds are in the order of -1.7m/yr. (NE-direction) to 3.2m/yr. (governing SW-direction). From the data, the reference seabed level (RSBL) was determined, indicating the predicted lowest seabed level during the lifetime of the wind farms in the Borssele area. Comparison of the RSBL with the most recent bathymetry from 2010 showed a predicted maximum seabed level lowering of approximately 8 meters Conclusion Borssele wind farm zone (BWFZ) has a highly dynamic soil morphology that can lead to a maximum seabed lowering of approximately 8 meters. This lowering should be taken into account when designing the offshore constructions. In the second phase of this study, all findings will be updated and validated using an up to date (still to be performed), high-resolution bathymetrical dataset. The findings will be complemented with GIS-files with different recommendation zones for foundations and electricity cables. 26

27 5.3 Archaeological assessment Introduction The purpose of the study is insight in archaeological aspects that can play a role in the development of the wind farm zone Borssele. The main objectives of the study are: 1. Assess whether there are (indications for) areas with specific archaeological interest (wrecks and prehistoric life) at the Borssele wind farm zone. 2. If present, define expected location, size and dating of the areas with specific archaeological interest. 3. Determine the possible effect of the installation of offshore wind farms on the areas with specific archaeological interest. 4. Assess possibilities to mitigate the disturbance of areas with specific archaeological interest as a result of installing offshore wind farms. 5. Identify whether any further investigations should be carried out from archaeological point of view and make a recommendation on the scope and specifications of these investigations. 6. Define requirements for any activity carried out in the wind farm zone (investigations or monitoring activities, installation activities, operational activities) that could have an effect on archaeological aspects in the wind farm zone Supplier Vestigia Coastal & River Archaeology has been selected to perform the Archaeological desk study [9]. This subsidiary of Vestigia BV combines the offshore archaeology expertise of Vestigia and cooperating partners. Cotswold Archaeology, one of the largest suppliers of maritime archaeological expertise in the UK, ADC Maritiem and several freelance experts in the Netherlands and abroad are among the partners. Vestigia has a track record in maritime archaeological preparatory research for offshore wind and other offshore activities. For example, they provided research for NUON s offshore wind prospects, the Maasvlakte 2 and the COBRAcable between the Netherlands and Denmark Results The report assesses both the presence of early prehistoric sites from an era when the North Sea was still land, as well as historic shipwrecks, lost cargo and crashed airplanes. Prehistoric sites: 1. No early prehistoric sites have been identified within the wind farm itself, the nearest being 9 miles southeast of the wind farm zone. 2. If present at all, prehistoric remains are located at a depth of about 30 to 40 meters below present day sea level. This means that the site has been submerged by the expanding North Sea around 7000 BCE and therefore possible settlements will most likely be older. However, population density in North-western Europe during these early stages of prehistory was very low. Therefore, the density of archaeological traces of those people is also very low and the chance that the traces are well preserved even lower. Conclusion, the chances of encountering prehistoric archaeology within the wind farm zone are small (low sensitivity). 27

28 Historic shipwrecks: 1. Three shipwrecks have been found within the wind farm zone. The only identified wreck within the wind farm zone is the Alca Torda, a steel fishing vessel of 54 tons which sank in 1973.This wreck can be considered of no archaeological value. There are a number of unidentified obstructions reported within the wind farm zone at present. These could either be wrecks, part of wrecks or anchors, cargo or garbage. They may also be the remains of aircrafts, lost in the World War II. In the immediate vicinity of the wind farm zone several historic wrecks are attested, most from the 19th of 20th century. The best-known wreck, of high archaeological importance, is the East Indiaman t Vliegend Hert, which sunk in The recorded shipwrecks and objects may or may not be of archaeological significance. As long as it is impossible to determine the significance, these locations are best avoided during development. 2. Vestigia has found no records of systematic surveys with side-scan sonar or other geophysical techniques within the wind farm zone, mainly because the area has never been of commercial interest. The reported finds are therefore more or less random discoveries and their low number is in no way a reflection of the actual density of historic archaeological sites. More undiscovered shipwrecks and other historical objects are therefore very likely present within the wind farm zone. Therefore, the chance to encounter historic archaeology (shipwrecks, airplanes, etc.) for the entire wind farm is average (medium sensitivity). Figure 11 Chart from Spiegel der Zeevaerdt (1588). BFWZ is approximately located inside the red rectangle. Note: the North is in the left bottom corner 28

29 5.3.4 Conclusions and recommendations No early prehistoric sites have been identified within the wind farm itself and the chance to encounter prehistoric archaeology within the wind farm zone is small. Therefore, further archaeological survey with the intention to establish prehistoric sites is not recommended. Historic shipwrecks have been identified in the area and shipwrecks of high archaeological significance have been found in the vicinity, leading to an average chance to encounter historic archaeology. It is recommended to perform a geophysical area survey (side scan sonar or multi beam, for example simultaneously with UXO surveys). Based on the recommendations of Vestigia, RVO.nl has determined to start a geophysical survey in Q1 of Upon discovery of an archaeological site, its historic and scientific value has to be assessed. In case of archaeological significance, one can either avoid the site or salvage the remains, the latter incurring high costs. 5.4 Unexploded Ordnance (UXO) assessment Introduction The UXO desk study gives insight in the areas in the Borssele wind farm zone with an increased risk of encountering unexploded ordnances (UXO s). The main objectives of this study are: 1. Identify constraints for offshore wind farm related activities in the Borssele wind farm zone as a result of the presence of UXO s. 2. Identify areas within the Borssele wind farm zone that should preferably not be used for the installation of offshore wind farms and/or cables. 3. Identify requirements from UXO perspective that should be taken into account for: a. Determining the different concession zones in the wind farm zone. b. Carrying out safe geophysical & geotechnical investigations. c. Safe installation of wind turbine foundations. d. Safe installation of cables Supplier REASEuro has performed the UXO Desk study [10]. The company has experience in offshore UXO studies; most notably serving dredging, wreck recovery and offshore wind construction. Since 2012, REASEuro has been involved with several offshore projects in the Persian Gulf performing data analysis, project risk assessment and coordination of demining activities. The project team members for this assessment have specific North Sea-experience from their previous employment at Van Oord Dredging and the demining department of the Royal Dutch Navy. 29

30 5.4.3 Results The wind farm zone Borssele and its surrounding areas were the scene of many war related activities in World War I and World War II. In both world wars a large number of naval mines were deployed in the North Sea, which where only partially recovered after the war. Moreover, the wind farm zone Borssele is located in the main flight path of Allied bomber raids. As a consequence a large number of aircrafts have crashed in the North Sea and many bombs were dropped in the North Sea (see Figure 12). Figure 12 A scan of the sea bed in the English Channel shows the Dornier-17 German bomber, buried under the sand since World War II Finally, after the war, ordnances could have been moved as a result of fishing, tidal streams and seabed migration. Due to the previous facts the entire wind farm zone Borssele is to be considered a UXO risk area. This result is validated by the fact that since 2005 fishermen have found over 20 UXO s. The UXO can be sensitive to hard jolts, change in water pressure and acceleration with an amplitude >1m/s 2. A detonation can lead to serious damage to equipment and injuries to crewmembers. The possible presence of UXO in the area, however, is no constraint for offshore wind farm related activities. With proper UXO Risk Management the risks can be reduced to a level that is as low as is reasonably practicable (ALARP). A main challenge in UXO Risk Management at Borssele wind farm zone is de abovementioned movement of the UXO over the sea bottom. This can lead to resurfacing UXO s that were buried during preliminary scanning and introduction of new UXO s by sea currents or fishing activities. Therefore, monitoring needs to be a crucial aspect of all development phases, closely integrated into the UXO Risk Management. 30

31 The report provides a number of recommendations for each phase in the development: 1. Preparation phase a. A geophysical (bathymetric) survey in order to gain insight in geomorphology and identify objects. RVO.nl has determined to start with a geophysical survey in Q1 of 2015, based on the recommendations of REASeuro. b. In case of any soil intrusive operations, the area affected by the operations has to be searched for and cleared from UXO s. The clearance operation has to be conducted by a certified EOD-company. 2. Execution Phase a. UXO related risk assessment based on the first draft of the wind farm design and optimisation of the design based on the outcomes. b. UXO risk mitigation strategy, which includes a search for and safe removal of UXO. Because the validity of the collected data is limited in time, it s recommended to minimise the time lapse between the survey and the actual installation works. 3. Operational phase a. Because of tidal streams, mobility of sand waves and seabed usage the possibility that UXO are moved within the wind farm zone after completion of the construction activities has to be taken in to account. b. Maintenance & Monitoring Plan. Figure 13 shows an example of UXO risk management campaign during the development of an offshore wind farm. Figure 13 UXO Risk Management in each phase of the wind farm development Conclusion and recommendations UXO from both world wars can be present at the site. The site is therefore considered an UXO risk area. However, with proper UXO Risk Management the risks can be reduced to a level that is as low as is reasonably practicable (ALARP). Due to the highly dynamic soil morphology, it is recommended to conduct the UXO search and removal operations at short notice prior to the construction activities. The validity of the collected magnetometer survey data in regards to tidal streams, mobility of sand waves and seabed usage has to be taken into account when planning the survey and construction operations. Time lapse between project phases has to be limited as much as possible. 31

32 5.5 Metocean Study Introduction The Metocean Desk Study defines the relevant meteorological and oceanographic (metocean) data that are input for design calculations of tenderers for the Borssele offshore wind zone. The study covers the following aspects: 1. Identification of all meteorological and oceanographic parameters that will become part of the design basis to be used to carry out design calculations for offshore wind farm in the Borssele wind farm zone. 2. Identification of relevant meteorological and oceanographic parameters that are input for wave and wind persistence tables for the wind farms and offshore high voltage stations in the Borssele wind farm area Supplier Deltares has performed the Metocean desk study [11]. The institute has an extensive track record in offshore wind, with most studies related to topics such as scour prediction and protection, metocean conditions, wave loads, cable burial depth and morphodynamics. Moreover, Deltares has an extensive track record on other offshore wind farms in the near vicinity of the Borssele wind farm zone. DNV-GL has been contracted to certify the methodology and the results of the study. The study is currently finished, but certification is still pending. Therefore, the results of the study, provided below, are still preliminary Results The general objective of this study is to determine the metocean conditions (wind, wave, current and other meteorological parameters) present at the Borssele wind farm zone. The metocean report is setup for each of the four wind farm sites separately. In each report, the data presented is related to a specific reference point that has been selected a representative point for the total site. In order to determine the local variation over each one of the four sites of the BWFZ, dedicated numerical modelling is required for wave, water level and current related parameters. The local modelling simulations cover a relative long period (20 years), sufficient for deriving the requested metocean parameters. These local variations in the metocean parameters are mainly caused by the variation in the bathymetry, i.e. the presence of sand banks and sand waves. Therefore, the numerical modelling will take into account the bed level variation in detail. The wind conditions are based on the high resolution HARMONIE data for KNMI. The project was conducted partly in collaboration with KNMI. The metocean conditions are assessed by means of detailed analyses of available model (reanalysis) and measurement data. These data are analysed statistically for each selected output location. The analyses comprised normal conditions and extreme conditions, for several recurrence periods of 1, 2, 5, 10, 50 and 100 years, depending on the requirements following the DNV-GL standard. The wind, wave and current normal conditions are computed empirically and given in terms of frequencies of joint occurrences and the extreme climate in terms of return values obtained by means of extreme value analyses. The parameters specifically related to hub height are determined for heights of 70m, 80m, 90m, 100m and 150m. 32