National Grid Delivers 2.4 GW of New Transmission Connections in 2025

National Grid reported that it connected 2.4 gigawatts (GW) of new generation capacity to its electricity transmission network in 2025, including several large renewable energy projects. This follows the 3 GW of connections delivered in 2024 and brings the total generation capacity connected in England and Wales over the past five years to 12.6 GW.

In April, the 373 megawatt (MW) Cleve Hill Solar Park, described as Britain’s largest solar array, began exporting electricity after being connected to the grid at the Cleve Hill substation in Kent.

During the summer, Statera Energy’s Thurrock Storage project, identified as the country’s largest battery energy storage system (BESS), was connected at the Tilbury substation in Essex. The project provides 300 MW of flexible capacity to support electricity supply across London and the southeast.

In September, National Grid completed upgrades and commissioning work at the Lackenby substation in North Yorkshire to support the connection of RWE’s Sofia offshore wind farm, described as one of the largest offshore wind projects in the world.

A National Grid spokesperson said, “Connecting these landmark projects highlights the strong progress Britain is making towards its clean energy ambitions.”

In addition to these projects, National Grid completed work on more than 400 MW of additional battery energy storage connections. These included a 150 MW facility at Ferrybridge substation in West Yorkshire, a 100 MW project at Thornton substation in North Yorkshire, and further connections at substations in Enderby in Leicestershire, Rainhill in Merseyside, and Bredbury in Greater Manchester.

On the demand side, approximately 0.5 GW of new demand connections were delivered in 2025. This included the energisation of the Little Horsted substation in East Sussex in November, supporting UK Power Networks in supplying homes and businesses in the area.

Network upgrades also continued in Greater London, including commissioning a new power feed from the Willesden substation as part of the Willesden and Kensal Green Connection project to support a new data centre in Park Royal. Additional London Power Tunnels circuits were energised during the year to reinforce electricity supply in the capital.

National Grid stated that it is participating in the connections reform programme led by the National Energy System Operator to prioritise projects that are most ready and most needed to meet future energy system requirements.