Each substation, whether existing or new, can have different configurations or equipment construction depending on what is needed, and to comply with regulations. Here we look at the different types of substations customers can connect into.
Useful key terms and equipment definitions:
In England and Wales, energy projects over 50 MW* typically connect to the transmission network via substations. These connections are made through designated “bays.” Large electricity users, such as data centres and factories, may also connect at a transmission level.
However, not all substations have spare capacity. If space and system conditions allow, substations can be extended to add new bays. National Grid Electricity Transmission (NGET) will construct the substation extension, while the customer is responsible for building their own bay.
The 200-tonne transformer will be transported to Overton Substation, completing delivery of all eight supergrid transformers to the new substations at Overton and Monk Fryston.
The transformer will be transported by a specialist delivery vehicle from Teesport Docks, in Middlesbrough, over 50 miles via the highway network to our substation on Overton Road. The delivery route will follow the A19, through villages including Birdforth, Thormanby and Shipton by Beningbrough before turning onto Overton Road where the Overton Substation is located.
As the Transmission Owner for England and Wales, we are key to connecting a variety of assets to the high voltage network. Before a customer is ready to connect, certain processes must be followed to ensure the safe operation of the network and surrounding equipment.
In a standard connection, the customer contracts with the National Energy System Operator (NESO), who then appoints National Grid Electricity Transmission (NGET) to build the connection.
To ensure the safety of our workforce and the public while this is carried out, we need to temporarily close a short section of Upper Road between 17 and 21 October 2025. The closure is expected to be in place between 08:00 and 17:30. Outside of these hours, the road will be reopened. The work will be carried out by Balfour Beatty, on behalf of National Grid.
To ensure the safety of our workforce and the public while this is carried out, traffic management measures are expected to be in place between 17 and 21 October 2025. These will operate between 08:00 and 17:30. Outside of these hours, the traffic management will be removed. The work will be carried out by Balfour Beatty, on behalf of National Grid.
During the times outlined above, temporary traffic lights will be in place. Advance warning signs have been displayed, and the work areas will be clearly marked with cones and barriers.
From September 29 to October 3, over 1,500 National Grid volunteers took part in more than 70 projects that included:
To ensure the safety of our workforce and the public while this is carried out, traffic management measures are expected to be in place between 14 and 24 October 2025. These will operate between 08:00 and 17:30. Outside of these hours, the traffic management will be removed. The work will be carried out by Balfour Beatty, on behalf of National Grid.
