Both transmission and distribution future energy scenarios have highlighted significant growth in energy storage within the UK over the next decade. Both National Grid ESO and WPD anticipate that a high growth scenario could see more than 10GW of energy storage being connected in the UK by 2030. WPD currently has over 840MW of energy storage either connected or accepted in the West Midlands licence area and this is beginning to impact on the reinforcement requirements for transmission assets at the T-D boundary.

The industry continues to develop flexibility services as an efficient option for the connection of embedded generation, giving generation customers more choice and lowering costs to consumers. Storage provides a similar function to generation; hence this RDP is looking to extend the flexibility arrangements given to generation so that they apply for storage demand. This will enable storage projects to become part of the solution to network capacity issues rather than capacity planning standards being a potential blocker to them.

This RDP seeks to allow energy storage, or other customers who can provide flexibility to the system, to participate in these emerging whole system energy markets and receive revenues for delivering services when the system needs flexibility to deliver capacity in constrained areas. A high-level plan of RDP deliverables can be found below.

High level plan

We are collaborating with UK Power Networks through a regional development programme for the South East Coast area of England. The aim of the programme is to maximise the opportunities for further efficient deployment of distributed resources and reduce overall system costs for energy consumers. The South East Coast area was the clear choice for this study, as it is one of the most complex network areas in Europe. It has several interconnections to continental Europe, either currently in service or due to be commissioned, a nuclear power station, and a significant volume of renewable and traditional energy resources connected to the distribution network.

The Regional Development Programme looks across the whole-system landscape to identify key areas of development to unlock additional network capacity, reduce constraints and open up new revenue streams for market participants. This project will significantly enhance transmission and distribution systems coordination and control, creating whole system efficiencies and providing new tools and resources to manage system constraints – ultimately reducing costs for customers. The Programme fosters innovation in a ‘design by doing’ environment that supports the effective management of the electricity network on a ‘whole-system’ basis. At the same time, it supports the development of DSO capabilities.

We are collaborating with Western Power Distribution through a regional development programme for the South West area of England. The exposed position of South West England has enabled it to become a favoured location for renewable generation. It is also an area where modelling indicates the network’s ability to absorb that energy may be an issue after 2020. If the region is to fulfil its potential of meeting future governmental green energy targets the programme needed to not only analyse the requirements and capabilities of the network but also ensure future capacity requirements can be managed.

The programme also had to tackle the question of what is the most cost-effective way of enabling renewable generation to connect to the whole network. Conventional means of increasing the network capacity by installing new infrastructure to enable the power to flow may not be the most cost-effective solution for renewable energy, due to its intermittent nature. As a result, other plans need to be on the table.

We are collaborating with both SP Transmission and SP Distribution through a regional development programme for the South West area of Scotland. There is great potential for renewable electricity generation in this region, but that requires extensive and costly network reinforcements to get the energy to where it is needed by conventional means; so, we are looking at new ways to use technology and operational methods to provide cost efficient outcomes for the renewable developments in the region.

In order for the System Operator to utilise the full potential of the future transmission network in South West Scotland in an economic and efficient manner, it has been identified that both transmission connected generation and Distributed Energy Resources should compete on a fair and equitable basis for access to the network. It is therefore proposed to develop innovative arrangements for the connection of developments to the network and provision of constraint management services to maximise the utilisation of the transmission network and allow the management of the system going forward. The Regional Development Program is designed to enable the necessary frameworks to be put in place to achieve this goal on a “Whole System” basis.

High Level Plan

The North-West part of the electricity network has high potential for wind resources. In particular, the Heysham GSP is at its’ limit in terms of thermal capacity for reverse power flow across the existing three Super Grid Transformers (SGTs) and switchgear fault level design limit. By 2020, the Heysham GSP is expected to have 564MW of DER connected to the distribution network. Installation of a new SGT was suggested to add more thermal capacity at the Heysham GSP. However, delivery of an SGT is often an expensive and time consuming solution and, in this case, the utilisation of the full capacity of the SGT would be restricted by the existing switchgear’s fault level limitations.

This Reginal Development programme (RDP) aims to analyse the Heysham GSP and the distribution network behind it as a ‘whole system’, in order to deliver the most economic solution for GB Consumers.

High level plan