ScottishPower Renewables is investigating the potential for a new offshore windfarm in the southern north sea, called East Anglia TWO.
The proposed site, being developed by East Anglia TWO Ltd, is approximately 31km from its nearest point onshore; the port of Lowestoft and 32km from Southwold. It would cover an area of 255km2 and would have an operational capacity of up to 900 megawatts which is enough to power approximately 742,412 UK households*.
*Calculated taking the number of megawatts (800) multiplied by the number of hours in one year (8,766), multiplied by the average load factor for offshore wind (36.7 %, published by the Digest of United Kingdom Energy Statistics), divided by the average annual household energy consumption (3,900 kWh).
The proposed East Anglia TWO Offshore Windfarm has the potential to make a substantial contribution to UK 2030 energy targets by meeting nearly 5% of the UK offshore wind cumulative deployment target for 2030.
The proposed offshore development area comprises of:
- Wind turbines – up to 75 wind turbines would cover an area of 255km2. The maximum height to the blade tip would be 300m above sea level.
- Offshore platforms – up to four electrical platforms connected by platform link cables to collect the electricity, a construction, operation and maintenance platform and a meteorological mast.
- Subsea cables – up to 200km of inter-array cables connect the turbines to the offshore electrical platform. A maximum of two export cables, buried or protected on the seabed will then transport the electricity to shore. The two cable routing options are the preferred choice in terms of engineering and environmental constraints, in particular avoiding the geological Coralline Crag sea bed feature.
The onshore development area comprises of:
- Landfall location – Horizontal Directional Drilling (HDD) will be required to install the ducts to avoid any construction works on the beach, and a minimum setback distance of 85m from the cliff top will allow for natural coastal erosion based on the potential 100-year erosion prediction and will not compromise the integrity of the cliff.
- Underground cables –Up to six single core onshore cables and up to two Fibre Optic cables will be buried for a maximum of 9km. For the majority of the route, trenching will be undertaken in which to place the ducts through which the cables are pulled. Manhole covers may be required at some locations to allow for maintenance. Where certain features need to be avoided/crossed, HDD techniques may be used to minimise environmental impacts and disruption.
- Public highways – a number of road improvements or modifications could be required to facilitate the safe ingress and egress from the public highways for construction access or at locations on the existing public road network in order to facilitate construction traffic and/or construction-related deliveries.
- Onshore substation – a maximum building height of 15m and external electrical equipment of up to 18m in height is proposed and the substation will cover an area of 36,100m2 (190x190m).
- National Grid substation – to accommodate the electricity produced by East Anglia TWO (and East Anglia ONE North) an Air Insulated Switchgear (AIS) or Gas Insulated Switchgear (GIS) substation would be required. The maximum height of the AIS would be 13m with a footprint of 140x325m and the maximum height of the GIS would be 16m with a footprint of 140x120m.
- National Grid realignment works – one additional pylon within the vicinity of the National Grid substation as well as up to four cable sealing ends and potential additional replacement or upgrade works will also be required for East Anglia TWO (and East Anglia ONE North).
Consultation is a key driver of the Environmental Impact Assessment (EIA) process, and continues throughout the lifecycle of the projects, from initial stages through to consent and post-consent. Extensive community and stakeholder consultation has informed the designs (particularly the site selection) and helped to develop an environmentally sustainable proposal for East Anglia TWO.
Phase 1 Consultation (October to November 2017)
- Introduced East Anglia ONE North and East Anglia TWO to new stakeholders
- Consulted on potential constraints to the locations for onshore infrastructure
- Explained the EIA scoping process
- Introduced the projects to those potentially impacted by the visual impacts of the offshore windfarm.
As part of the consenting process ScottishPower Renewables (SPR) submitted Scoping Reports for East Anglia TWO and East Anglia ONE North to the Planning Inspectorate (PINS) for their consideration in November 2017. These Scoping Reports requested a Scoping Opinion to agree the methodology for undertaking the full EIA.
Phase 2 Consultation (March to April 2018)
- Phase 2 marked the start of statutory consultation which involves engagement with bodies and organisations as required by the Development Consent Order (DCO) process
- It provided further information on the Onshore Study Area within which SPR intends to site the projects’ onshore electrical infrastructure
- Set out the refinement of the study area
- Sought opinions on the viewpoints selected to assess the visual impact of the offshore wind turbines
Phase 3 Consultation (May to August 2018)
- Consulted on the refinement of the Indicative Onshore Development Area
- Presented Zone 7 in Friston as the preferred substation location
- Consulted on mitigation that the projects could adopt, particularly in terms of cable routing and at the substation location
Phase 3 Consultation was designed to focus on consultation regarding the Indicative Onshore Development Area and aimed to gather the community’s views on mitigation.
Phase 3.5 Consultation (September to November 2018)
- An additional phase of consultation to present Broom Covert, Sizewell, as an alternative substation site option
- Explored options to relocate the existing Sizewell C reptile mitigation land
- Proposed improvements to parts of the local road network
- Presented refinement of the proposed area required for National Grid Electrical Transmission (NGET) to connect their proposed substation to the existing Overhead Line
Following this additional phase of consultation, with a primary focus of exploring the viability of an alternative substation site, Grove Wood, Friston was concluded to remain SPRs preferred site location.
Phase 4 Consultation (January to March 2019)
The consultation focused on the Preliminary Environmental Information Report (PEIR), which set out the proposed infrastructure, its potential impacts and the environmental, social and economic effects and mitigation measures proposed.
During Phase 4 Consultation, prescribed consultees, local authorities and those with an interest in the land were consulted in accordance with Section 42 and Section 44 of the Planning Act. Views were sought on the project proposals as well as on the PEIR, which included information on the following:
- Need for the Project
- Policy and Legislative Context
- Site Selection
- Environmental Impact Assessments
- Project Description
Feedback received during the consultation phase in response to the PEIR will further refine the proposed East Anglia TWO project design and the Environmental Impact Assessment (EIA).
Development Process Update
Further refinement of the project design and Environment Impact Assessment (EIA) will be based on consultation responses received in relation to the PEIR. The final results of the EIA will be presented in the Environmental Statement which will accompany the Consultation Report in the final DCO application.
The proposed East Anglia ONE North project is also in the pre-application stage and its application programme runs in parallel with East Anglia TWO, however they will be submitted as separate DCO applications. The proposed onshore development area has been developed to allow for the construction of both projects. At this stage it is not known whether both projects would be constructed simultaneously or sequentially. Therefore onshore topic assessments will include the two cumulative assessment scenarios.