It’s T-time! All T-pylons now erected on Hinkley Connection Project

  • All 116 world-first T-structures now complete as part of the Hinkley Connection Project

  • Last of 232 diamond ‘earrings’ lifted onto a T-pylon between Yatton and Kenn in North Somerset

  • 36 of the new T-pylons between Woolavington and Loxton were energised in March

National Grid’s Hinkley Connection Project reached another milestone with the completion of all 116 of its iconic new T-pylons, which will connect six million homes and businesses in the South West to home grown, low-carbon energy. 

The last of the T-structures’ 232 diamond-shaped insulators – which hold the high-voltage conductors in a diamond ‘earring’ shape – was recently lifted by crane into place on a T-pylon between Yatton and Kenn in North Somerset by National Grid and principal contractor Balfour Beatty.

Representing a world first for pylon design, the first T-pylon to be built was constructed in September 2021 near East Huntspill.

T-pylons are quicker to erect than traditional lattice pylons, and 47 more T-pylons were completed – including installation of the conductors – by the end of 2022.

36 new T-pylons between Woolavington and Loxton were energised in early 2023, meaning high voltage electricity is now running along the new T-pylons, through cables under the Mendip Hills Area of Outstanding Natural Beauty and via the newly built substation at Sandford.

At the same time work began to build the 68 T-pylons running north of Sandford substation to Portbury. With the hanging of final diamond insulator, those 68 T-pylon structures are now complete. 

All the T-pylons will be energised by the end of 2024. Before then, conductors will be hung from the T-pylons, and the last of 249 traditional lattice pylons and 67km of overhead wires will be removed from the landscape to make way for the new electricity connection.

Roxane Fisher-Redel, Senior Project Manager for National Grid on the Hinkley Connection Project, said: "National Grid’s T-pylons are the first new design for overhead electricity lines in over a century and will play a central role in connecting low-carbon energy to millions of people when Hinkley Point C begins generation.

"Erecting all the 116 T-pylon structures is a huge milestone and now we look ahead to 2025 and full completion of this project, which will play such a key role in transmitting cleaner, homegrown energy around the UK – enough to power six million homes and businesses."

The T-pylons were designed to reduce the visual impact of the 57km connection route on the landscape as a direct response to community feedback.

At 35m high, they are a third shorter than National Grid’s traditional lattice transmission pylons and take up less room on the land.