Flexibility in Great Britain


This page contains details of the Flexibility Services that Electricity Networks in Great Britain are utilising from Distributed Energy Resources (DER). The sections below will help you understand how Electricity Networks are enabling local Flexibility Markets and offering different types of Flexible Connections as part of their business as usual (BAU) operations. As the Electricity Networks drive consistency and commonality across all services across the country, the ENA Open Networks Project is setting the strategy and ensuring the implementation of Britain’s smart grid, and making sure that all users benefit from it.

Open Networks Project

The Open Networks Project is a major industry initiative that will transform the way our energy networks operate, underpinning the delivery of the smart grid. The project seeks to enable the uptake of innovation and low carbon energy sources by homes, businesses, and communities in the UK, allowing them to take advantage of these new technologies to take control of their energy and lower costs.

As part of the Open Networks Project, a workstream dedicated to Flexibility Services (WS1A) has been created to look at how best to facilitate markets for flexibility, develop good practice and standardisation, and support the wider use of Flexibility Services by removing barriers. As Flexibility Services become more common throughout the country, the learn-by-doing approach of the Electricity Networks will enable real world learning to be fed back into the strategy developed by the Open Networks Project.

To find out more information about Open Networks, click here.

Introduction to Flexibility

More and more DER is becoming flexible, which can mean a range of things but ultimately means the ability to control or schedule demand and/or generation. Flexible Technology can include batteries, solar+storage, CHP, Electric Vehicles (EVs) and other technologies. As well as enabling the buying and selling of energy at specific times (also known as energy arbitrage), these Flexible Technologies can provide ‘Flexibility Services’ to Electricity Networks, to help solve congestion issues on the grid and release additional capacity, which in turn allows connection of more low carbon technologies such as renewables. 

Flexibility Commitment

In December 2018, DNOs created the ENA Flexibility Commitment, an agreement that saw them help to boost the use of smart energy technologies to reduce the need for building new electricity grid infrastructure.

The commitment marked the first step in expanding Flexibility Markets at a local level, allowing new low carbon technology to compete and complement traditional forms of infrastructure to drive down cost and de-carbonise the networks.

The full text of ENA’s Flexibility Commitment can be found here.

Flexibility Commitment: Six Steps for Delivering Flexibility Services

Building on ENA’s Flexibility Commitment, Our Six Steps for Delivering Flexibility Services defines how Flexibility Markets will work in practice.

It ensures that Electricity Networks become a level playing field for all customers with connected resources, open and transparent for all to participate in, and will help customers understand the methodologies and criteria that are used to procure and dispatch Flexibility Services from their DER.

The full text of Our Six Steps for Delivering Flexibility Services can be found here.

We are monitoring the implementation of the Flexibility Commitment: Six Steps across the GB Transmission and Distribution Networks. The latest progress report for this implementation can be found here, and we will be updating this regularly.

Flexibility Figures

Since 2018, DNOs have been tendering and procuring for various Flexibility Services to help solve congestion in the local electricity grids. The below figures demonstrate the scale and size of these local Flexibility Markets across GB DNOs, as well as highlighting the National Grid ESO Contracted Flexibility Figures.

Last updated: April 2020

DNO Flexibility Stats

National Grid Flex Stats

ENA will be updating these figures every 6 months, to help customers understand the size of the market and ensure transparency across the country. 

A common defintion of the 4 real power products was developed and agreed through the Open Networks project and this can be found here. Currently most DNOs are procuring Flexibility Services that help solve network congestion (thermal constraints), but in the future this will expand to other services such as voltage and reactive power support.

Flexibility Timeline & Links 

Flexibility Services are now being procured by all Electricity Networks in Britian on a BAU basis. Below you can find a timeline of Flexibility Tenders across all of the GB DNOs for 2019 and 2020. We have also included the links to each of the GB DNOs Flexibility Tenders pages within the timeline, so you know how to get directly involved in these markets. 

A PDF or image of this schedule can be downloaded here.

Flexibility Projects

 A range of innovation projects are bring run by the Electricity Networks to trial, test and further understand how Flexibility Services can suport the planning and operation of Electricity Networks.

The ENA Smarter Networks Portal is to be the definitive place to find information, updates and learning from these flexibility related innovation projects. All outputs and learnings from these projects are open and publically available on the Portal.


Flexible Connections

What is a Flexible Connection?

Electricity Networks are planned and designed on the basis of meeting the local peak demand or peak generation placed on them. This peak might only occur for a few hours on a handful of days a year. When a new customer (demand or generation) requests a connection to the network, companies assess whether the capacity requested will breach demand or generation limits at this peak time. If it does, then reinforcement of the network is traditionally required. Under the distribution connection charging methodology (which is approved by Ofgem), connecting customers are required to make a financial contribution to the cost of that reinforcement.

On the back of successful trials, many companies are allowing new customers to connect to the network, without reinforcement, even where the capacity requested by that customer exceeds the peak network limits. Companies are allowing this, on the basis that the customer agrees to being constrained off when the network is reaching its capacity limits. This can reduce the cost of connecting to the network and also the time to connect, as works are not required. Flexible Connections are sometimes referred to as non-firm connections, constrained connections or active network management schemes. 

Network companies have also been offering customers alternative options to connect to the electrity grid beyond the traditional 'firm' connection. These offers allow customers to connect their DER cheaper and quicker than it would for a fully firm connection.

The table below shows the current scale of Flexible Connection solutions on the distribution networks in GB:

Flexible Connections Stats

Many of the Flexible Connections terms being offered by Electricity Networks have emerged from innovation projects and via the Customer Experience Workstream of the Open Networks Project (WS2). Under this Workstream a range of different Flexible Connection types were formed by networks, in collaboration with the industry. These can be found here.

Flexible Connections Contacts

All Electricity Networks are keen to ensure that these Flexible Connection products are made more widely available, to give customers choice when connecting to the Networks. Individual Networks will be able to advise on specific Flexible Connection application requests, and you can contact each of them as follows:

Electricity North West

National Grid Electricity Transmission

Northern Powergrid

SP Energy Networks

Scottish and Southern Electricity Networks

UK Power Networks

Western Power Distribution


For queries related to Flexibility please contact Randolph Brazier, Head of Innovation & Development at ENA: [email protected].

For Regulation specific queries, please contact John Spurgeon, Head of Regulatory Policy at ENA: [email protected]