Hornsea 3 & Norfolk Vanguard

Letter to The Rt Hon Greg Clark MP Secretary of State for Business, Energy and Industrial Strategy

The Rt Hon Greg Clark MP
Secretary of State for Business, Energy and Industrial Strategy 1 Victoria Street

Dear Greg,

Dear Jason Ormiston,

Re: Hornsea 3 and Norfolk Vanguard

Please quote our reference in all correspondence with this office

Our Ref: ZA32533-JK 29 November 2017

I write following a meeting I have had with three representatives of the ‘Friends of North Norfolk’ – Ian Shepherd, Chris Wheeler and Godfrey Sayers.

They came to see me to discuss concerns about both the Vattenfall project and the Orsted project.

I enclose a copy of a letter prepared by Ian Shepherd which he brought to the meeting. I also enclose a note focusing on the ‘Rochdale Envelope’ which was prepared by William Horabin.

I would be grateful if you could respond to all of the issues set out in the letter and the separate note.

I would like to focus on two specific issues which I would like your direct response to.

The representatives of Friends of North Norfolk made the point very strongly to me that leaving open the question of HVAC versus HVDC to a very late stage of the process means that there is not a proper debate about the competing impacts of the two technologies. It seems to the Friends of North Norfolk that local people are being denied a proper and open debate about this critical choice – apparently leaving it to the company and the regulator to decide at a very late stage. They make the point that the use of HVDC avoids the need for a relay station in open countryside. They also make the point that it appears as if the width of the land which will have to be protected, perhaps for many years, would be much wider with HVAC compared to HVDC. This will have a significant impact on the local environment, on farming, historic buildings and on the natural environment and they feel that this is a crucial issue that should be capable of being properly debated and considered as part of the main application. HVDC could be a significant mitigation of all these concerns. They also make the point that horizontal drilling (laying the cabling without disturbing the surface of the land) should be considered over more stretches of the route particular areas of important landscape value.

Finally, I would be most grateful if you could clarify with me some detail the difference in the width of the protected land for the cabling with HVAC versus HVDC. What width of land will need to be protected if the HVAC route approach is used? What width of land will be required to be protected if the HVDC approach is followed?

Are you prepared to release all of the technical specifications and impacts for HVAC versus HVDC so that there can be a proper and informed debate locally about these competing impacts.

For my part, I share the concerns of the representatives of Friends of North Norfolk and believe very strongly that there needs to be an open and full and informed debate about the competing impact of HVAC versus HVDC. I fail to understand why it is appropriate to leave this to the last possible moment without a sufficient and informed debate. I make all these points whilst being very clear that I am absolutely supportive of the developement of offshore wind energy– as are the Friends of North Norfolk. There is sometimes a conflation of these issues with claims against those with concerns that this means that they are anti- wind energy. This is unreasonable and there needs to be a clear distinction made. These are legitimate concerns being raised by local people which need to be properly considered.

I look forward to hearing from you as soon as possible. Yours sincerely,

The Rt Hon Norman Lamb MP
Member of Parliament for North Norfolk Dictated by Norman Lamb




  1. The Friends of North Norfolk support green energy and the use of efficient offshore wind farms to produce clean electricity. However, such wind farms and the necessary offshore/onshore infrastructure must not be allowed to result in major cumulative harm to the environment, specifically the landscapes, seascapes and ecology, all of which constitute priceless heritage assets that are designated as of the highest importance both nationally and internationally. Hornsea Project Three will, on its own, be one of the largest offshore wind farms in the world and the scale of it, when considering Hornsea Projects One and Two (for which Dong Energy already have approval and are currently developing) is massive and it seems likely that Hornsea Project Four will very likely follow on.
  1. Dong Energy have applied what is known as ‘The Rochdale Envelope Approach’ and reserve the option to choose between High Voltage Direct Current, (HVDC) or High Voltage Alternating Current (HVAC) Transmission schemes if they receive approval for both within the one application. The Rochdale Envelope Approach enables a Developer to avoid repeated applications for approval to changes in the design of a project and consequential delays in implementation. It should be used to encourage better designs and allowance for rapid advances in technology, which can reduce environmental impacts. In short, it is to allow for a project to evolve over a number of years but within clearly defined parameters. However, we strongly argue that the Rochdale Envelope Approach should not be allowed in cases such as this when changes in the features/ specifications of the design options are so fundamental, and where it allows for a Developer to manipulate a consent for purely profit motives rather than to gain a superior solution from an environmental perspective.


  1. Guidelines regarding the use of the Rochdale Envelope Approach were issued by the former Infrastructure Planning Commission (IPC) in IPC Note 9 (February 2011). They still remain relevant to the assessment process.
  2. The PEIR and Consultation by Dong Energy fail to meet these guidelines.


  1. Further, they do not satisfy the underlying principles applicable to public consultation over new development requiring Environmental Impact Assessment. Unless they are adequately addressed this current process will be legally flawed.


  1. The details provided in the PEIR and Non-technical Summary do not describe the Proposal as clearly and simply as possible. There are no proper accurate and detailed photo montages/ wireframe images, particularly for the very large offshore or onshore HVAC Compensator/ Booster Station Installations to enable a ready visualisation/ appreciation of their visual impact. No proper description of the equipment e.g. lightning protection equipment which might be up to 17.5 metres in height which is 5 metres higher than buildings/ equipment.


  1. It is noteworthy that Dong Energy changed the original consent for Hornsea Project One to add the option to use HVAC Transmission and have subsequently chosen the HVAC Transmission option albeit in a less sensitive landfall and cabling area. In the case of Race Bank, Dong Energy have changed the position of offshore substations so that where originally they were to be out of sight over the horizon they have been moved to within the turbine array area and will now be visible from many highly sensitive viewpoints within the Norfolk Coast AONB and the Norfolk Coast National Trail.


  1. There are clear and significant advantages of HVDC Transmission over HVAC Transmission. HVDC is used in long distance sub-sea and underground transmission systems linked to offshore and on-land power generation operations. Indeed it has cost advantages in terms of fewer cables and lower power losses for transmission distances over 50km. Hornsea Project Three Transmission will be over 170km in total length from offshore substations to the proposed grid connection at Norwich Main Substation. Most importantly in this case HVDC would clearly have a much less harmful environmental impact since it will not require massive offshore or onshore Reactive Compensation Booster Stations sited and visible in extremely sensitive locations.
  2. The flexibility allowed by use of the Rochdale Envelope should only be available to provide a choice of which design/ configuration of HVDC Transmission System is eventually utilised. It should not be allowed to provide the Developer with the option of the far more ecologically and environmentally harmful HVAC Transmission System purely on grounds of finance.


  1. The consequences of allowing such an accommodation would be perverse since in the quest and overall desire for clean energy, great harm to ecology and environment of the highest value would result.


  1. Dealing with the Hornsea Project Three Preliminary Environmental Impact Report (PEIR) and impacts/ consequences for North Norfolk, we would wish to draw attention to the following:-


ï    Cumulative and inter-relational impacts of the various elements of the Project during all phases, but most crucially the operational phase, have not been fully assessed or have been inaccurately assessed.


ï    Individual impacts have been incorrectly assessed as not significant and even if accurately assessed as not significant become significant when their inter-relationship is assessed.

ï    Critically the cumulative effects/ impacts with other major developments (such as Race Bank, Dudgeon and Sheringham Shoal offshore wind farms and cabling works and potential proposals such as the Bodham and Selbrigg wind turbines and the Vanguard/ Boreas wind farm) have not been recognised, let alone given due weight.


  1. We question the many deficiencies in PEIR Volumes 2 and 3 and the areas where Dong Energy has failed to properly assess/ consider such cumulative impacts.


  1. PEIR Volume 2, which deals with offshore, impacts because of inter-relationship and cumulative harm to/ with onshore receptors, notably:

–     Chapter 4 Marine Mammals. The importance of both grey and common seal colonies, as an ecological and tourist asset.

–     Chapter 5 Offshore Ornithology.

–     Chapter 6 Commercial Fisheries.

–     Chapter 10 Seascape and Visual Resources.


  1. HVAC Booster Stations will be visible from very important sensitive areas of AONB, Heritage Coast, SSSI, and RAMSAR sites – as evidenced by PEIR Volume 2, Chapter 10, and Figure 10.3 Zone of Theoretical Visibility of Offshore HVAC Booster Stations.


  1. Please note that Race Bank Offshore Wind Farm was presented as being barely visible but in reality has a significant impact upon a very sensitive and important stretch of coast, which holds AONB, and Heritage Coast Designations. The turbines can clearly be seen inland from other sensitive and important SSSI areas e.g. Kelling Heath.


  1. PEIR Volume 3, which deals with onshore impacts. We have great concerns that the additional cables, very large offshore and onshore Reactive Compensation Installations and works which would be required if HVAC Transmission is used would have a major adverse impact on very sensitive Receptors taken cumulatively with other major developments, either recently completed or proposed. Both the Dudgeon and Sheringham Shoal Wind Farms make landfall at Weybourne; and if HVAC Transmission is utilised it will mean more and very much greater works over a prolonged period both to the East and West affecting a key part of the Norfolk Coast AONB, Norfolk Heritage Coast and the Norfolk/ English National Trail.


–     Chapter 4 Landscape and Visual Resources.

–     Chapter 5 Historic Environment.

–     Chapter 6 Land Use and Recreation.

–     Chapter 8 Noise and Vibration.

–     Chapter 11 Inter Related Effects.


  1. Mitigation proposals of whatever means are not acceptable for long-term adverse impacts, causing such harm to the Norfolk Coast AONB, Heritage Coast, Nationally and Internationally Designated Sites.


  1. The majority of the North Norfolk Coastline is recognised, both nationally and internationally, for its exceptional landscape and ecological value with a number of overlapping Designations including the Norfolk Coast AONB, the North Norfolk Heritage Coast, many SSSI, SAC, RAMSAR sites and Marine Protection Areas/ MCZs.



  1. Panoramic sea views of the Coastal Edge, and the interaction between the landscape and sea are an essential part of its unique character made up by the dynamic coastal landforms and processes, ecological interdependences, biodiversity and cultural, architectural, economic, historic and archaeological features.


  1. The Coastal Plain from Holme-next-the-Sea to Weybourne in particular has a wilderness quality, which is rare in lowland England. Nationally, it is one of the few remaining examples of undeveloped coast with such a sense of remoteness and tranquillity.


  1. The Consultation and Response Timetable has been too tight to properly assess such a massive project, and the volumes of data and information – beyond the resources of most authorities and public bodies, let alone ordinary folk.


  1. We, the Friends of North Norfolk, request that the deficiencies in the PEIR and Consultation Documents provided by Dong Energy, which we have briefly outlined are properly addressed.


  1. Most importantly we would challenge the use of HVAC Transmission when HVDC Transmission would achieve a win, win, outcome for North Norfolk, the Environment and the Nation’s energy supply in a viable and sustainable way.


  1. We understand that in order to make their final decision as to which system to adopt, DONG have promised to undertake a full technical/feasibility appraisal of HVAC and HVDC So as to fulfill that promise completely we request that the conclusions of this appraisal are made know to all consultees and within a time frame for them to respond


  1. In conclusion, we request that all the foregoing are adequately and properly addressed before DONG submit their proposals to the Planning Inspectorate.


Thank you.


The Friends of North Norfolk.






























Single building: length ( 150
Single building: width (m) 30
Building: height (m) 125
Maximum lightning protection height (m)

3.8 Onshore infrastructure Onshore export cables

  • 8.1  Onshore export cables will be buried and connect to the offshore export cables at the landfall point (which has yet to be selected along the North Norfolk coast) and transfer the power onwards to the onshore substation (potentially via an onshore HVAC booster station in the case of HVAC, see 3.8.9 to 3.8.10). 

  • 8.2  Onshore export cables differ in design to offshore export cables due to the differing conditions they operate in (i.e. marine and terrestrial) as well as the differing installation methods employed. Whereas offshore export cables usually include multiple conductors within a single cable, onshore cables usually contain only a single conductor, and therefore there are more cables. 

  • 8.3  The offshore and onshore export cables will be jointed together at a location very close to the landfall on the landward side. Site investigations at the landfall (consisting of a borehole and resistivity survey) is due to be undertaken between Quarter 4 2016 and Quarter 1 2017 and will confirm the exact approach to installing export cables at the landfall. At the present time, horizontal directional drilling (HDD), trenching, dredging, jetting, ploughing, rock cutting or vertical injection are being considered as options for laying the cables at the landfall. 

Page 34 of 459

  • 8.4  Up to six export cable circuits will be required. The cables will be buried either in multiple separate trenches (up to six trenches, each containing one circuit), or with some circuits combined in a single larger trench. The cables may be installed directly into open trenches, or pulled through pre-installed ducting. The cables will be installed within an onshore ECR corridor, with an expected width of 80 m (this includes both the permanent installation area and temporary working area). The width of the permanent and/or temporary areas may change where obstacles are encountered. 

  • 8.5  Transition Joint Bays (TJB) will be required for the jointing between the offshore and onshore cables. This is a subsurface concrete box that will be accessed via a manhole. There will be up to eight TJBs with an area of approximately 250 m2 each. Those TJBs will be located above MHWS and will likely be completely buried, hence the need for manholes for access. 

  • 8.6  Joint Bays will be required along the onshore route in order to join sections of onshore cable together. They will be similar to the TJB, but with smaller dimensions of approximately 150 m2. They will be located approximately every 1 to 2.5 km along the onshore ECR. As with the TJBs, these will likely be completely buried, with manholes for access. 

  • 8.7  The exact onshore ECR corridor will be finalised prior to the EIA being completed once the landfall location is known. The cable routing will consider a wide range of human, biological and physical constraints as well as technical and commercial considerations. 

  • 8.8  The onshore export cable may need to cross infrastructure and obstacles such as roads, railways and rivers. The detail of how this will be carried out will be explored further when more is known about the onshore ECR corridor, however it is likely that a various methods will be used, including open cut trenching, and HDD, depending on the nature and complexity of each crossing. Hornsea Three will aim to undertake all major crossings, such as major roads, rivers and rail crossings using HDD. 
Onshore HVAC booster station 

  • 8.9  An onshore HVAC booster station is required for the HVAC transmission only; it is not required for HVDC transmission. 

  • 8.10  The onshore HVAC booster station would have the same purpose as an offshore HVAC booster station(s) and contain similar equipment. The equipment will either be housed within a single or multiple buildings, in an open yard or a combination of the above. The exact location, as well as requirements for landscaping, would be determined based upon a wide range of human, biological and physical constraints as well as technical and commercial considerations. The site selection methodology for the onshore HVAC booster station is described in Chapter 4: Site Selection Methodology and Consideration of Alternatives. The Design Envelope for the onshore HVAC booster station can be seen in Table 3.19 below. 
Table 3.19 Design Envelope: onshore HVAC booster station. 

* Note – the onshore HVAC booster station may comprise of a single building or multiple buildings on the same site.

Environmental Impact Assessment: Scoping Report

Parameter Maximum Design Envelope
Permanent area of site for all infrastructure* (m2) 25,000
Single building: length (m) 150
Single building: width (m) 30
Building: height (m) 12.5
Maximum lightning protection height (m) 17.5

Page 35 of 459

Onshore substation

  • 8.11  The onshore substation contains the electrical components for transforming the power supplied from the offshore wind farm to 400 kV and to adjust the power quality and power factor, as required to meet the UK Grid Code for supply to the National Grid. If a HVDC system is used it will also house equipment to convert the power from HVDC to HVAC. The equipment will either be housed within a single or multiple buildings, in an open yard or a combination of the above. 

  • 8.12  The Design Envelope for the onshore substation for both HVAC and HVDC options can be seen in Table 3.20 below. Hornsea Three will connect to the National Grid at the Norwich Main 400 kV substation, located between Swardeston and Stoke Holy Cross in South Norfolk. 
Table 3.20 Design Envelope for onshore substation. 
Grid connection export cable 

  • 8.13  A further section of buried onshore export cabling is required to connect the Hornsea Three onshore substation with the National Grid substation. This section of cabling will be similar in design to the onshore export cabling, but must be HVAC at 400 kV. 
Construction compounds 

  • 8.14  The onshore works at the landfall, the onshore HVAC booster station (if required) and onshore substation will require the establishment of temporary construction compounds for the storage of materials and plant, as well as space for small temporary offices, welfare facilities, security and parking. 

  • 8.15  Construction compounds of various sizes will also be required along the onshore ECR corridor, for laydown and storage of materials, plant and staff, as well as operations such as out drilling works, where there are crossings of other infrastructure. 

  • 8.16  The construction compounds, if deemed necessary, will be removed and sites restored to their original condition when construction has been completed. The exact number, location and size of the compounds required will be confirmed once a substation location and onshore ECR have been developed. New temporary roads or access tracks for construction traffic are likely to be required at various points along the route, connecting compounds and construction sites to existing nearby roads. All compounds will be reinstated to their former condition following the construction phase, unless it is considered necessary to retain the use of a compound for a longer period post-construction. 

A meeting of the Cabinet of North Norfolk District Council will be held in the Council Chamber at

The Council Offices, Holt Road, Cromer on Tuesday 05 September 2017 at 10.00am

Dear all,


Please find attached NNDC’s proposed response to DONG’s plans for bringing the cabling from the Hornsea Three Project ashore at Weybourne and the cabling route on to Norwich National Grid Substation. As it reads it would appear that NNDC have accepted (do they know something we don’t) that DONG will use HVAC power transmission over HVDC. Should DONG choose that option and as previously mentioned – they do not have to make a decision about which system to use until after the Secretary of State has given the project the go ahead- there would be a need for an off-shore booster HVAC booster station will be visible from within the Norfolk Coast AONB and many protected sites/special areas -see PEIR Volume 2 Chapter 10 page 15 Figure 10.3 Zone of Theoretical Visibility (all areas coloured yellow), plus another on-shore booster station which at the moment proposed for land between Edgfield and Little Barningham, some of the least spoilt rural landscape we have here. This is the current spec for it.


  • Table 3.19 Design Envelope: onshore HVAC booster station. 

* Note – the onshore HVAC booster station may comprise of a single building or multiple buildings on the same site.

Environmental Impact Assessment: Scoping Report

Parameter Maximum Design Envelope
Permanent area of site for all infrastructure* (m2) 25,000
Single building: length (m) 150
Single building: width (m) 30
Building: height (m) 12.5
Maximum lightning protection height (m) 17.5


Should Dong decide to use HVDC none of this would be required, which leaves me puzzled as to why NNDC (who have a responsibility re AONB status, Conservation Areas and Wildlife Sites) have not suggested that DONG take this option. The danger with NNDC’s acceptance of HVAC is that should DONG later decide to site their booster stations in other locations (and none of this is set in stone) NNDC have already accepted the idea in principle and would have some difficulty opposing it.

From the research we have done HVDC would seem to be the way forward, other wind farms are already using it for long distance power transmission, and it would integrate more readily with the proposed European HVDC super grid.


NNDC do have serious concerns regarding the disruption that bringing power from the largest wind farm in the world will have on the local economy with the real possibility that work on this project, and Hornsea Four following on behind could go on through three stages for 11 years. This is potentially one of the most significantly damaging projects the North Norfolk will see in any of lifetimes and we need to get our concerns on the table ASAP, we also need to persuade, NNDC (if only by our presence) that this needs a much more robust response than they are mounting at present. Through the lifetime of this project Dong will have benefitted from billions of pounds of taxpayers money, the least they can do is accept the concerns of these taxpayers. The difference in cost between HVAC & HVDC would, compared to the overall cost of this massive scheme be minuscule. So if you can spare the time please try to go along and stand at the back for this meeting.

Hornsea Project Three.

The Biggest Wind Farm in the World is to be built off the Yorkshire coast, but at present there are no plans to take the power ashore there. At the moment Dong Energy’s preferred route is to bring it ashore at Weybourne impacting one of the most beautiful

Untitled.jpegstretches of coast we have.  Burying the cable will result in considerable disruption,but once buried there would be little impact on the landscape, however, that is only the case if Dong were proposing to take the option of using HVDC = High Voltage Direct Current, but at present it looks as if they are going for HVAC = High Voltage Alternating Current which is cheaper but requires booster stations along its length to avoid power loss. The first of these stations would be needed at Weybourne and would be a very large and intrusive feature in the landscape; finding out more about what such a structure would look like is unsurprisingly very difficult, but all the information we have suggests a large structure  covering a large area. As it stands at the moment Dong will not be required to decide which of these voltage transmission options to take until after planning consent has been given, in other words after the horse has bolted. The wind farm is unstoppable as the relevant permissions have all been obtained, but where and how it comes ashore has not. We have had no answers to our questions as to why the Lincolnshire or Yorkshire coasts are unsuitable, or why they will not guarantee the use of HVDC.  The Friends of North Norfolk have a mighty task ahead if they are to influence any of this, it has government support and the huge momentum gathered by the bandwagon of climate change . We will need to recruit as much support as we can from those who love this coast. The Pros and Cons of electrical transmission can be seen here.






Hornsea Project Three Offshore Wind Farm

Phase 1.B: Consultation Summary Report

Onshore HVAC Booster Station

At the Phase 1.B events, we explained that if Hornsea Project Three is developed using a HVAC transmission system, then a booster station offshore and / or onshore could be

Several respondents expressed a strong preference for the Project to use the Direct Current option if feasible, the biggest concern being the potential visual effect the booster station might have on the rural environment. Several attendees stated it was dif cult to express a comment on this without being able to visualise what the

required. At the rst set of events (Phase 1) held 6 onshore HVAC booster station could look like. Any such onshore 123789

in October and November 2016, we presented
our original search area for the onshore HVAC booster station (up to approximately 10 km from the coast) and asked attendees to make us aware of aspects within this area that they would like us to take into consideration when siting this element.

At the Phase 1.B events, we consulted on three potential options for locating the onshore HVAC booster station (see gure 3). These options were selected following an initial constraint mapping exercise, which indicated that the southern half of our search area was preferable for locating this infrastructure. Further information on the site selection process will be available in the Site Selection chapter of our PEIR (to be issued in summer 2017) (see Next Steps). The three onshore HVAC booster station options and associated cable corridors were labelled B, A & C (from west to east/or north to south) and attendees were asked to comment on these options. We have subsequently given these options local names to aid identi cation. Option B, located closest to Holt, will hereafter be referred to as “Holt Farm”. Option A, the central route, will hereafter be referred to as “Pond Hills”. Option C, the most southerly route, will hereafter be referred to

as “Little Barningham”.

We received a considerable amount of feedback on this aspect of our proposal through our feedback forms, conversations at the events and through our communication channels. Residents expressed strong concerns about an onshore HVAC booster station being located at the site known as “Pond Hills”, explaining that this site is valued by local communities and is renowned for its natural beauty and diverse wildlife. Others were concerned about the proximity of the “Holt Farm” site to residential properties and raised concerns about the potential effect that the site might have on the Glaven Valley.

HVAC booster stations have not yet been developed in the UK. However, this point is very valid and therefore visualisations will be available at the next set of events for comment. The Project recognises these concerns and will attempt to minimise any potential effect on the local environment where possible. However, at this point in time it is necessary to retain the exibility for both HVAC and HVDC transmission systems. HVDC technology has yet to be applied for offshore wind farms in the UK and hence the technical feasibility

of this option cannot yet be guaranteed for this Project.





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