7.4.4.2 Landfall Onshore Cable Route
Total Page:16
File Type:pdf, Size:1020Kb
Environmental Statement Volume 4 – Introductory Annexes Annex 4.4.2 Landfall, onshore cable route and converter/substation location selection PINS Document Reference: 7.4.4.2 APFP Regulation 5(2)(a) January 2015 sdf Copyright © 2015 All pre-existing rights reserved. The concepts and information contained in this document are the property of Sinclair Knight Merz (Europe) Limited. Use or copying of this document in whole or in part without the written permission of Sinclair Knight Merz constitutes an infringement of copyright. SMart Wind Limited Hornsea Offshore Wind Farm Liability Project Two – Environmental Statement This report has been prepared by Sinclair Knight Merz, with all reasonable skill, Volume 4 – Introductory Annexes care and diligence within the terms of their contracts with SMart Wind Ltd. Annex 4.4.2 – Landfall, onshore cable route and converter/substation location selection This report has been prepared on behalf of and for the exclusive use of Sinclair Knight Merz (Europe) Limited’s Client, and is subject to and issued in connection with the provisions of the agreement between Sinclair Knight Merz and its Client. Sinclair Knight Merz accepts no liability or responsibility whatsoever for or in respect of any use of or reliance upon this report by any third party. Document release and authorisation record PINS document reference 7.4.4.2 Report number UK06-050200-REP-0022 Date January 2015 Client name SMart Wind Limited SMart Wind Limited 11th Floor 140 London Wall London EC2Y 5DN Tel 0207 7765500 Email [email protected] i sdf Foreword The proposed onshore cable route and HVDC converter/HVAC substation for Project Two is immediately adjacent to Hornsea Project One. The synergies were identified at an early stage and the route/site selection was designed to inform the EIA for both Project One and Project Two. As of such this report while initially produced for Project One is directly applicable to Project Two and sets out the factors that influenced the onshore export cable route selection and HVDC converter/HVAC substation site selection for both projects. ii sdf Table of Contents Table of Figures 1 Introduction .......................................................................................................................... 1 Figure 1.1 Project One area of search. ...................................................................................2 1.1 Purpose ................................................................................................................ 1 Figure 3.1 ‘Long list’ of identified landfall sites. .......................................................................6 1.2 Background ........................................................................................................... 1 Figure 4.1 Desktop environmental constraints summary. .......................................................9 2 Assumptions ........................................................................................................................ 3 Figure 4.2 National Grid gas pipelines and electrical infrastructure. ..................................... 10 2.1 Search Area .......................................................................................................... 3 Figure 4.3 North of the Humber ‘long list’ of routes and constraints. ..................................... 11 2.2 Overhead Lines/Cable .......................................................................................... 3 Figure 4.4 South of the Humber ‘long list’ of routes and constraints. .................................... 12 2.3 Impact Assessment Approach .............................................................................. 3 Figure 4.5 Overview of alternative route 11b. ....................................................................... 17 2.4 Technology ........................................................................................................... 3 Figure 5.1 Onshore HVDC converter/HVAC substation site identification. ............................ 19 2.5 Number of Cables and Easement Required ......................................................... 3 Figure 6.1 Project One final onshore cable route. ................................................................. 21 2.6 Onshore HVDC Converter/HVAC Substation Land Requirements ....................... 4 2.7 Programme Requirements .................................................................................... 4 Table of Tables 2.8 Assessment Evaluation Criteria ............................................................................ 4 Table 2.1 HVDC and HVAC technologies. .............................................................................3 3 Selection of Landfall Site ..................................................................................................... 5 Table 3.1 Landfall assessment. .............................................................................................7 3.1 Initial Identification ................................................................................................ 5 Table 4.1 Onshore route ranking matrix (without Humber crossing assessment). .................8 3.2 Site Investigation .................................................................................................. 5 Table 4.2 Humber crossing ranking assessment. ................................................................ 14 3.3 Short Listing .......................................................................................................... 7 Table 4.3 Preferred route ranking assessment (including Humber crossing assessment). .. 16 3.4 Selected Landfalls ................................................................................................ 7 Table 5.1 Onshore HVDC converter/HVAC substation location assessment. ...................... 20 4 Selection of Onshore Cable Route ....................................................................................... 8 4.1 Initial Route Design ............................................................................................... 8 4.2 Initial Short Listing ................................................................................................ 8 4.3 Further Site Investigations .................................................................................. 13 4.4 Humber Crossing Assessment ........................................................................... 13 4.5 Identification of Preferred Onshore Cable Route ................................................ 16 4.6 Finalisation of Preferred Route ........................................................................... 16 4.7 Accessibility for Project Two ............................................................................... 16 4.8 HVAC Connection Technology ........................................................................... 16 5 Selection of Onshore HVDC Converter Station Site .......................................................... 18 5.1 Potential Site Identification .................................................................................. 18 5.2 Site Investigation and Stakeholder Engagement ................................................ 18 5.3 Identification of Preferred Onshore HVDC Converter Station Site ...................... 20 5.4 HVAC Substation ................................................................................................ 20 6 Conclusion ......................................................................................................................... 20 iii sdf Acronyms Acronym Full term ES Environmental Statement FGP Fisher German Priestner – Land Ownership Consultants GIS Geographic Information System HDD Horizontal Directional Drill HVAC High Voltage Alternating Current HVDC High Voltage Direct Current Metoc-Intertek Energy and Water Consultants NGET National Grid Electricity Transmission SKM Sinclair Knight Merz – Engineering Consultants TEC Transmission Entry Capacity iv sdf 1 INTRODUCTION 1.1 Purpose 1.1.1 The purpose of this document is to outline the optioneering and selection process which was accomplished to determine the optimum landfall site, onshore cable route corridor and onshore HVDC converter/HVAC substation location for the connection of the SMart Wind Limited Hornsea offshore wind farm Project One. 1.2 Background 1.2.1 Project One is located over 100 km from the East Yorkshire and East Lincolnshire coast. In addition, National Grid Electricity Transmission (NGET) identified Killingholme 400 kV substation to be the connection point for Project One, some 20 km inland from the coast and on the south bank of the River Humber with a capacity of up to 1.2 GW. 1.2.2 The second project from the Hornsea offshore wind farm is also proposed to be connected to Killingholme 400 kV substation. Potential efficiencies could be gained from both projects utilising the same connection corridor and this was considered throughout the selection process, although focus was made primarily on Project One. 1.2.3 Considering the length of connection required to the offshore wind farm and the generation capacity, it was assumed that a High Voltage Direct Current (HVDC) connection would be required. The initial assessments made to identify the optimum connection were based on HVDC technology, the suitability for a connection using HVAC was however also considered. 1.2.4 An appropriate area of search for offshore cable route corridors, landfall sites, onshore cable route corridors and onshore