Project development and appraisal process

When considering the need for new infrastructure, National Grid Electricity System Operator (NGESO) and National Grid Electricity Transmission undertake a phased Options Appraisal process. This has been used to identify our Strategic Proposal for the Yorkshire GREEN project. 

In doing so, we have balanced technical, socio-economic, environmental, programme and cost considerations in accordance with our statutory and licence obligations. 

When refining the design and routeing of new electricity transmission lines for Yorkshire GREEN, we have undertaken a phased Options Appraisal process, which includes the consideration of alternatives to the Project. This process involves the following key stages:

What is the Options Appraisal process?

Our Options Appraisal is carried out in two parts: a Strategic Options Appraisal and then a more focused Options Appraisal. 

The Strategic Options Appraisal process is a robust and transparent methodology which we use to compare different options for new infrastructure and to assess associated advantages and disadvantages across a range of criteria, including environmental, socio-economic, cost and technical factors. 

We begin by looking at all of the technically feasible options which meet the determined need, which may cover a very wide geographical area and a number of different technologies. We then narrow down the options through a process of careful analysis with engineers, environmental consultants and internal National Grid experts.  

The Strategic Options Appraisal concludes with the preparation of a Strategic Proposal Report, which also takes account of our licence commitments. For the Yorkshire GREEN project, the Strategic Proposal is for a new section of overhead line to link together two existing overhead lines.   

The next stage of the Options Appraisal is to focus in on broad corridor locations for the new overhead lines, and identified siting areas for specific elements of infrastructure, such as substations. These are assessed by environmental consultants, engineers and other experts to consider and understand the environmental, socio-economic, cost and technical factors.  

We then hold internal workshops on how to minimise known effects, taking account of the technical solutions and environmental implications. The whole Options Appraisal process concludes with a Corridor and Preliminary Routeing and Siting Study. In the case of the Yorkshire GREEN project, this report identifies the preferred corridor for the overhead lines, together with broad siting areas for the associated infrastructure.  

At each stage of the process we gain more detailed information about the constraints and issues that might affect a particular option. As we learn more, we back-check at each stage to see if any new information has come to light which affects any conclusions previously made regarding technology or options. 

Why do we do Options Appraisal?

Options Appraisal provides a framework that allows us to identify and balance technical, socio-economic, environmental and cost considerations in selecting a Strategic Proposal. It also enables us to document, in a transparent way, the information on which we have based our judgements. 

The information we collect as part of Options Appraisal informs our discussions with stakeholders, including the public. Alongside community and stakeholder consultation, Options Appraisal is a key tool in helping us develop and make decisions on projects. All projects are different, and where we need to deviate from this process, we will explain the reasons and ensure that we meet our obligations.