The recent Triton Knoll decision shows the approach which the Secretary of State can take where the Generation elements of an Offshore Wind Farm project are promoted ahead of the Offshore Transmission and Onshore Grid Connection elements.

It is an important decision because it shows how the commercial realities of large-scale Offshore development (where grid connection and transmission elements can remain uncertain during the application for the wind-farm) can be accommodated in planning decisions.

The project was promoted by Triton Knoll Offshore Wind Farm Limited (TKOWFL). Approval was granted on 11 July 2013 for The Triton Knoll Offshore Wind Farm Order 2013, a Development Consent Order under the Planning Act 2008. The wind farm comprises up to 288 wind turbines, with up to 1200MW capacity.

The Offshore Wind Farm application did not include subsea export cabling or onshore grid connection infrastructure. The reason was that the prospective grid connection points had changed during the pre-application stage, and TKOWFL had decided to proceed with the preparation of the wind farm application and Environmental Statement with reference to an indicative grid corridor to avoid significant delay. It was made clear that the Offshore/Onshore Transmission and Grid Connection elements would be the subject of subsequent consenting applications.

Given the preliminary nature of the Offshore Transmission and Onshore Grid Connection elements, the Triton Knoll decision required the Secretary of State to consider the approach to be taken to three important questions: (1) the approach to Environmental impact Assessment, (2) whether there could be more than one application for different elements of the overall project, and (3) whether there should be any restriction linking development of the Wind Farm to the subsequent Transmission and Connection works.

  1. Environmental Assessment

The Secretary of State specifically noted that the question of adequacy of the ES in covering the effects from consequential development (connecting infrastructure outside the Order application site and not provided for within the Order) was raised by Interested Parties and the Panel during the Examination process. One Interested Party had specifically queried the degree to which it was possible to assess the whole proposal in the absence of clarity about the detail of the grid connection.

The Secretary of State referred to relevant National Energy Policy, the EC Directive on environmental assessment, and the UK EIA regulations, and concluded that the environmental information provided and the EIA process undertaken were adequate for the purpose of considering the wind farm application.

National Policy Statement EN-3 states that where the precise location of cabling routes/substations is not known, a cabling/substation corridor should be identified and the EIA should assess the effects of including this infrastructure within that corridor.

Overarching National Policy Statement NPS-1 also envisages that an applicant can proceed with a proposal without a firm grid connection offer (noting the commercial risks associated with such a step rest with the applicant alone) but in such circumstances the applicant needs to provide sufficient information to satisfy the requirements of the EC Directive, including indirect, secondary, and cumulative effects, encompassing information on grid connections.

The Triton Knoll decision noted that the EC Directive allows EIA information to be limited to that “which is relevant to a given stage of the consent procedure and to the specific characteristics of a particular project or type of project and of the environmental features likely to be affected”. The Directive also allows submitted information to be limited by the current state of knowledge. The UK EIA Regulations provide that the information required is limited to that which can be “reasonably required”, having regard “in particular to current knowledge”.

Taking these requirements into account, the Panel had concluded that the ES provided adequate assessment of indirect, secondary and cumulative effects of the development and “on grid connections to the extent necessary for this offshore proposal”. The Secretary of State agreed with the Panel’s broad conclusions on the environmental information submitted by TKOWFL and the EIA process undertaken, and considered it was adequate for the purposes of his consideration of the wind farm application.

He also stated that he was satisfied that “it was not necessary or indeed possible for TKOWFL to submit detailed information about the anticipated grid connection for the proposal as part of the Application or to assess this in the supporting ES, given in particular that any grid connection will have to be the subject of subsequent approval(s) and assessment(s)”.

  1. One or more applications?

Overarching National Policy Statement EN-1 describes the approach to be taken to Grid Connection. It recognises that it may be the case that the applicant has not received or accepted a formal offer of a grid connection from the relevant network operator at the time of the application, although it is likely to have applied for one and discussed it with them, and that this is a commercial risk the applicant may wish to take for a variety of reasons.

So although the government envisages that wherever possible applications for new generating stations and related infrastructure should be contained in a single application, or in separate applications submitted in tandem which have been prepared in an integrated way, this may not always be possible, nor the best course in terms of delivery of the project in a timely way.

It is explicitly recognised in EN-1 that the level of information on the different elements may vary, and that in some cases applicants may decide to put in an application that seeks consent only for one element but contains some information on the second. Where this is the case the applicant should explain the reasons for the separate application. The applicant must also ensure that they provide sufficient information to comply with the EIA Directive including the indirect, secondary and cumulative effects (encompassing information on grid connections), and the Secretary of State must also be satisfied that there are no obvious reasons why the necessary approvals for the other element are likely to be refused.

In the Triton Knoll decision the Secretary of State restated these requirements of policy, and agreed with the view of the Panel that “there are no obvious reasons why the connection elements of the project would be likely to be refused, given the applicant would be able to bring forward a number of alternative routes or solutions to those indicated”.

  1. Linkage of Wind Farm to Transmission infrastructure?

The Secretary of State rejected a recommendation by the Panel for the inclusion of a requirement in the Order that no works on the offshore generating station or associated offshore development should commence until the Secretary of State had confirmed in writing that all the necessary consents for the connection and transmission works had been obtained.

This had been proposed by the Panel for a combination of two reasons: firstly, so that any assessment of mitigation for the onshore works and assessment of contributions by the developer under a s.106 agreement would relate to the project as a whole and would not be restricted in scale only to the subsequent applications for the grid connection infrastructure; and secondly so that there would be a “functional and consenting link between two elements of the same project” that would allow onshore and offshore elements to be considered cumulatively when the onshore impacts of the wind farm were better known at the time of subsequent applications for connection elements.

On the question of cumulative assessment, the Secretary of State noted that NPS EN-1 envisages that any impacts of further development will normally be dealt with in the consenting process for that development, and continued “in particular the Secretary of State notes that any subsequent supporting EIA assessment for grid connection infrastructure would also need to consider cumulative impact with the offshore wind farm development”.  Following the detailed assessment of the Triton Knoll project the Panel had found that the visual impacts of the offshore development are very limited, and that to the extent that a judgment can be made, the limited offshore effects of construction in the DCO area, due to its distance from the shoreline, will significantly limit cumulative effects as observed from the same coastal locations. The Secretary of State therefore considered that “the potential cumulative impact of the offshore element of the overall project is not likely to be a significant component of the impact of the onshore element of the project”.

On the question of mitigation, the Secretary of State commented that “the consenting processes in place in relation to the onshore infrastructure are sufficiently robust to ensure that the impacts of the infrastructure are appropriately mitigated”, and given his conclusions on potential cumulative impact he also rejected the suggestion of a requirement linking the offshore and onshore elements for the purpose of assessing mitigation and Section 106 contributions.