Triton Knoll Offshore Wind Farm Limited TRITON KNOLL ELECTRICAL SYSTEM Environmental Statement Volume 1 Chapter 4: Site Selection and Alternatives April 2015, Revision A Document Reference: 6.2.1.4 Pursuant to: APFP Reg. 5(2)(a) Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement - Volume 1 Copyright © 2015 Triton Knoll Offshore Wind Farm Limited Triton Knoll Offshore Wind Farm Limited All pre-existing rights reserved. Triton Knoll Electrical System Liability Copyright © 2014 Triton Knoll Offshore Wind Farm In the preparation of this document, Triton Knoll Offshore Environmental Statement Limited Wind Farm Limited (TKOWFL), a joint venture between RWE InnogyAll preUK-existing (RWE) rights and reserved.Statkraft UK, and subconsultants Volume 1: Chapter 4 – Site Selection and Alternatives working on behalf of TKOWFL, have made reasonable efforts to ensure that the content is accurate, up to date and complete for the purpose for which it was prepared. Neither April 2015 TKOWFL nor their subcontractors make any warranty as to Copyright © 2014 Triton Knoll Offshore Wind Farm the accuracy or completeness of material supplied. Other thanLimited any liability on TKOWFL or their subcontractors detailed in theAll precontracts-existing between rights reserved. the parties for this work neither TKOWFL or their subcontractors shall have any liability for Drafted By: RWE any loss, damage, injury, claim, expense, cost or other consequence arising as a result of use or reliance upon any Approved By: Kim Gauld-Clark information contained in or omitted from this document. Date of Approval April 2015 Any persons intending to use this document should satisfy themselves as to its applicability for their intended purpose. Revision 2 Where appropriate, the user of this document has the obligation to employ safe working practices for any activities referred to and to adopt specific practices appropriate to local conditions. Triton Knoll Offshore Wind Farm Ltd Trigonos Triton Knoll Offshore Wind Farm Limited have been awarded Great Western Way EU TEN-E funding to support the development of the Triton Swindon Knoll Offshore Wind Farm Electrical System located in both UK Territorial waters and the UK’s Exclusive Economic Zone. The Wiltshire, SN5 8ZT funding which is to be matched will support a number of surveys, engineering reports, and environmental impact assessment studies for the Triton Knoll Electrical System. The T +44 (0)845 720 090 studies will form part of the formal documentation that will F +44 (0)845 720 050 accompany the Development Consent Order which will be submitted to the Planning Inspectorate. The sum of €1,159,559 I www.rweinnogy.com has been granted and the process to reclaim this funding is ongoing. www.rweinnogy.com/tritonknoll [email protected] ii Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement - Volume 1 Table of Contents 4 SITE SELECTION AND ALTERNATIVES ........................................................................ 4-1 Introduction .......................................................................................................................... 4-1 Legislation and Policy Context ............................................................................................. 4-2 Site Selection and Alternatives Process .............................................................................. 4-2 Transmission Technology .................................................................................................... 4-3 Interface Selection Assessment ........................................................................................... 4-4 Subsequent changes to ISA assumptions ......................................................................... 4-13 Site Selection Assessment................................................................................................. 4-15 iii Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement - Volume 1 1 4 SITE SELECTION AND ALTERNATIVES The location and nature of the Unlicensed Works at the existing National Grid Bicker Fen Substation. Introduction 4.3 The various components above collectively comprise the TKES. TKOWFL has undertaken extensive consultation with both statutory and non-statutory consultees on 4.1 This Chapter of the Environmental Statement (ES) has been prepared by Triton Knoll many aspects of the scheme as part of its consideration of alternatives. That Offshore Wind Farm Limited (TKOWFL) to set out the main alternatives considered consultation has provided important information and insight into the views and during the development of the Triton Knoll Electrical System (TKES). These concerns of statutory consultees and the public. However, given the engineering alternatives primarily relate to the locational choice for various components of the constraints of the electrical system TKOWFL has focussed its consultation on those TKES. However, alternatives were also considered with respect to the type of elements of the electrical works (such as the siting of the IEC and substation and technology that should be used. The process of the consideration of alternatives for micrositing of the onshore cable route) where those being consulted could genuinely Triton Knoll Offshore Wind Farm comprised two key phases: influence the final proposals. 1) The Interface Selection Assessment, being a process to decide where the TKES 4.4 Consultation was carried out on the shortlist of substation and IEC options that had should connect into the existing high voltage electricity transmission network been identified as feasible through detailed analysis, rather than an extensive longlist (known as the national grid); and of options which had not yet been filtered and therefore may not have been suitable. 2) The Site Selection process, which subsequently identified where all the elements This approach was taken to ensure statutory consultees and the public could influence of the Electrical System should be located and also included the selection of the the decisions being taken on genuine alternatives. Consultation undertaken with electrical technology that should be used. respect to alternatives is set out in each relevant section of this Chapter. TKOWFL and National Grid took the decision not to consult on the selection of the Onshore Interface 4.2 The two-stage process set out above commenced in 2009 with the acceptance by Point because, once appraised for technical feasibility, the process of evaluating the TKOWFL of a connection into the high voltage transmission network that is owned and identified options involved using high-level principles to primarily differentiate cost and operated by National Grid. Over a subsequent period extending from 2009 until 2014 high level environmental impact. Similarly, the selection of the landfall was principally TKOWFL has continued to evaluate and refine the options available to determine: driven by high level environmental issues and engineering and commercial constraints dictated by the practicalities of construction at the landfall, including the potential A suitable offshore cable route and cable landfall (including accommodation of impact of landfall location on offshore and onshore cable routing. Transition Joint Bays at the landfall); 4.5 Extensive detail on the alternatives process undertaken from 2009 to 2014 is contained A suitable location for an Intermediate Electrical Compound (IEC) approximately in four key documents: midway along the entire offshore and onshore cable route; The ‘Interface Selection Assessment Report’ and its appendix the ‘Interface A suitable onshore cable route from the landfall to the Onshore Interface Point, Selection Report’ (Application Document 8.18); including connection via the IEC and the Triton Knoll substation; The ‘Site Selection and Design Report’ and its appendix the ‘Alternatives A suitable location for a new Triton Knoll substation required to increase the Consultation Report’ (Application Document 8.17 and Appendix B of that voltage of the power exported by the offshore wind farm to the voltage of the 400 document). kilovolt (kV) transmission system; and 1 “Unlicensed works” are electrical works needed to connect Triton Knoll to the National Grid substation at Bicker Fen that National Grid is not required pursuant to its transmission licence to carry out itself. 4-1 Triton Knoll Offshore Wind Farm Ltd Triton Knoll Electrical System Environmental Statement - Volume 1 4.6 This Chapter meets the requirements of The Infrastructure Planning (Environmental 4.12 Furthermore Transmission Licence holders, being National Grid and the future OFTO, Impact Assessment) Regulations 2009, as set out in the next section. are bound by section 9 of the Electricity Act which requires them: Legislation and Policy Context ‘(a) to develop and maintain an efficient, co-ordinated and economical system of electricity transmission; and 4.7 TKOWFL has formally provided notification to the Secretary of State under Regulation (b) to facilitate competition in the supply and generation of electricity.’ 6(1)(b) of the EIA Regulations 2009, that it proposes to provide an Environmental 4.13 The above obligations on Licence holders generally and Transmission Licence holders Statement in respect of the proposed development. Therefore, in accordance with specifically, apply regardless of the consenting regime ultimately entered into or the Regulation 4(2)(a) of the EIA Regulations