Improving the Transmission/ Distribution interface Statement of Works process. March 2018 progress report

Transcription

1 Improving the Transmission/ Distribution interface Statement of Works process March 2018 progress report

2 Introduction The Statement of Works process has been under review nationally for the past three years. This report outlines what a Statement of Works is, the reasons for the review and the progress made by the end of March 2018, both nationally and within Northern Powergrid. It also gives an outline of the continuing work that will take place throughout the remainder of 2018 and in to What is a Statement of Works and why might I need one? The connection of generation to our network may have an impact on the GB transmission network, which is operated by National Grid. Embedding generation in our network cause changes in the overall flow of electricity in the network, though the impact is normally greatest near to the generator. As more generation connects to our network the impact on the transmission network becomes more significant and may result in parts of the transmission network needing to be reinforced. Our network connects to the transmission network through Grid Supply Point (GSP) substations. When the cumulative capacity of contracted generation within the network connected to a GSP reaches an agreed threshold then we will check with National Grid to see if there is any material impact on the transmission network. We request a Statement of Works from National Grid. The statement identifies whether the contracted generation has a material impact. If there is no impact then the generator can connect. However, if there is an impact then we must ask the generator if they still want to progress with their scheme. If the generator does want to progress then we will issue a confirmation of progression to National Grid. They will then develop a solution to reinforce the transmission network and present us with a formal modification offer laying out the works required and the costs / liabilities. These costs and liabilities are passed on to the generator by us. If they agree to the works then we will accept National Grid s offer and the work can commence. The generator may not be permitted to connect to the network until the works are complete. However, in some cases the generator can connect in advance of completion with or without constraints. How will I know if I need a Statement of Works? Sites with an overall generation capacity of less than 1MW are exempt from requiring a Statement of Works. If your site has an overall generation capacity of less than 50MW then we will let you know whether your offer is subject to a Statement of Works when we offer you a connection. Sites with a generation capacity of 50MW or greater will always need a Statement of Works. Why do we need to change the process? The existing process is effective in situations where the volume of generation wanting to connect to the network is small. Historically, we used to process two or three Statement of Works requests per year and we never received more than one generation request on a particular network at a time. The existing Statement of Works process typically takes six to nine months from beginning to end for a site where transmission works are required. It only deals with one customer on a

3 particular network at a time and can therefore cause long delays to project development while the generator is waiting to find out what additional liabilities they will be subject to. The combination of delay and uncertainty is not satisfactory for customers, especially in areas with high volumes of connection applications, where the sequential processing of Statement of Works requests introduces unacceptable delays. What are we doing about it? NPg are part of a national working group that is looking to reform the Statement of Works process. Over the past 18 months trials have been taking place at different places across the country to develop an improved process. The objective of the trial is to give the customer greater certainty of the transmission costs / liabilities as early as possible. Wherever possible we would like to be able to provide this information with the connection quotation, which takes up to three months to prepare. This will not always be possible, but the trials have already shown that many customers can receive this information with their connection offer. Although none of the main trials have been in our licence area, we have been able to learn from them and are now adopting the successful elements. The following processes are being developed within the different trials. They are listed here in order of complexity. Bulk Statement of Works requests - Rather than submitting a single request for each generator we can now collate a number of recently contracted generators together and issue a bulk request to National Grid. In areas with multiple generators contracting for a connection, this speeds up the time taken to identify whether any works are required. When works are required we are able to identify which generators are affected and whether any generators are able to connect without delay. Materiality limits where there is still spare capacity available on the transmission network, or the conditions for connection are already known, it may be possible to agree a materiality limit with National Grid. This allows us to self-manage generators up to an agreed capacity and to make offers to customers with a pre-agreed set of transmission conditions. If the cumulative contracted capacity exceeds the agreed materiality limit then we have to submit a new Statement of Works request to National Grid to agree a new limit, possibly with additional conditions. Typically the materiality limit is set at 50MW. This process requires us to share the current position with National Grid on a monthly basis but as long as we stay within the agreed limits we do not have to wait for National Grid s confirmation before customer s can connect. Planning limits in some cases it is possible to identify the specific amount of generation that would trigger additional works on the transmission network. Depending on what the limiting factor is, this might allow us to connect more than 50MW of generation into a network, but it will still be necessary for us to check with National Grid on a monthly basis in case the capacity is utilised by a generator connecting directly to the transmission network. There are potential interactivity issues between transmission and distribution customers and although this hasn t occurred yet, the working group is considering how it would be managed if it did happen.

4 Regional Development Programmes Some parts of the transmission network are so congested that adding generation on one part of our distribution network will reduce how much generation can be added to a different part of our network. In such circumstances a regional solution is required that groups the distribution networks together so that the same capacity is not accidentally used twice. Rollout within Northern Powergrid In 2017 we started submitting bulk Statement of Works requests to National Grid. All of our Statement of Works requests are now submitted on a bulk basis unless there is only one contracted customer in the GSP network. This is already reducing the timescales for obtaining details of the required transmission works. In addition, where we already know that some transmission-related works will be required, we now move straight to the Confirmation of Progression stage, also referred to as a Modification Application. This typically saves two months in the overall process by avoiding going through the initial Statement of Works request process. The bulk Statement of Works approach will suffice for areas where there are low levels of customer interest in installing generation. However, if the volume of applications is higher then the use of Materiality limits or Planning limits may be more appropriate. In February 2018 we received our first offer from National Grid with Materiality limits for Saltend North GSP. This arrangement will allow us to make further offers to other customers as well as allow the contracted customers that triggered the request to get connected. We are currently putting the necessary processes in place to allow us to share our contracted position with National Grid on a monthly basis so that any new customers can connect quicker. When we reach the agreed Materiality limit we will need to submit a new request to National Grid to identify if further headroom can be released. National Grid will be making a second offer to us in quarter two of 2018 using Materiality limits for West Melton GSP. We expect that going forward, our GSPs will transition to Materiality limits as and when we need to submit a Statement of Works request. Our aspiration is to eventually use Planning limits rather than Materiality limits, as they give greater visibility of the available capacity on the transmission network. However, it is more resource intensive for National Grid, as the limits may change on a regular basis due to interactivity across the transmission network. It is more likely that Planning limits will only be used where the volume of generation trying to connect makes it cost-effective for all parties. Regional Development Programmes (RDP) are only expected to be used in areas where there are significant constraints on the transmission network. We have not identified any parts of the transmission network within our area that would currently require this approach. However, we are continuing to monitor levels of activity in case an RDP is required. In December 2017 all of the network operators published their current plans for the rollout the different processes across their networks, on GPS by GSP basis. The publication can be found here. This is likely to be updated later in the year, as plans become more certain for each GSP.

5 Further work within the national working group in 2018 The national trials will continue to take place and our learning from Saltend North GSP, and from other sites where we are moving to Materiality limits, will be fed in to the overall trials. The development of the process for managing a GSP using Materiality limits is nearing completion and the working group is looking to submit the necessary code changes to formalise the trial arrangements on an enduring basis. This will not stop the detailed processes from continuing to be developed throughout 2018 to improve them. The process for using Planning limits is less well developed, though there has been more success in the trials in Scotland, as the works required when the Planning limit is exceeded had already been quantified for the networks being trialled. The trial model used in Scotland is being considered for use in England and Wales and may result in more Planning limits being established further south, but the work required to produce Planning limits remains significant. The trial use of RDPs will continue in the southeast and the working group will look to develop a standardised approach where an RDP is required. A customer feedback workshop was run in March 2018, which, as well as other things, identified that customers were not necessarily aware that they were in a trial area. The working group will be using the feedback received at the workshop to look for further improvements that can be made to the process and the way that information is shared with customers.