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Tickenham to Portishead
Current construction activity
Date from | Date to | Activity |
June 2021 | Late 2024 | |
May 2021 | 2024 | |
| October 2021 | 2023 | Removing existing pylons |
2018 | Ongoing |
Overview – Winter 2023
National Grid started work to build the north section of the Hinkey connection between Sandford and Seabank substations in July 2022.
We’re building 68 new T-pylons between Sandford and Portbury, and 27 traditional lattice pylons in Avonmouth to make the final connection into Seabank substation.
Using the innovative T-pylon design, reduces the height of the new infrastructure by a third. Standing at around 35 metres high – the T-pylon is a third shorter than traditional 400,000 volt steel lattice pylons which stand at around 48 metres. It also has a smaller footprint and uses less land.
To reduce the visual impact of the new 400,000 volt pylons, National Grid is removing 249 existing 132,000 volt lattice pylons, and overhead wires stretching 67 kilometres from the Somerset landscape.
Thank you from everyone working on the project for your patience and understanding as we progress with this vital work to connect six million homes and businesses to new sources of homegrown, low carbon energy, and help the UK meet its net zero ambitions.
Tickenham to Portishead timeline
Early 2020 to mid 2021
Underground the 132,000 volt overhead line between Nailsea and Portishead Substation
What we're doing:
Building temporary entrances and access roads to allow construction traffic to enter site from the local highway. You can find more information on our construction information page.
Building temporary construction compounds.
Building a 132,000 volt underground cable between Nailsea and Portishead Substation.
Building a new CSE pylon to connect the existing overhead line at Nailsea to the new underground cables.
This new underground cable section is being built as a direct result of feedback received during our consultation. It will enable us to completely remove the existing 132,000 volt overhead line that currently runs very close to people’s properties.
Mid 2021 to mid 2025
Build new 400,000 volt overhead line
What we're doing:
In this area, to minimise disruption, we will be sharing temporary construction compounds, and temporary entrances and access roads built for other elements of the build.
Building a new 400,000 volt overhead line from Sandford Substation to Seabank Substation (approximately 31.2km).
We will use T-pylons in this area.
Mid 2021 to mid 2025
Remove existing 132,000 volt overhead line
What we're doing:
Removing approximately 9 km of existing overhead line between Nailsea and Portishead substation that currently runs very close to people’s properties. We are removing this as a direct result of feedback received during our consultation.
Removing overhead line from the A368 in Sandford to Avonmouth, which will make way for, and minimise the visual impact of the new connection.
Early 2021 to mid 2025
Modify Portishead Substation and the overhead line to the east of the substation
What we're doing:
Making changes to the inside of Portishead Substation to enable the connection of the new 132,000 volt underground cable from Nailsea.
Building a temporary construction compound to the east of the substation.
Building temporary entrances and access roads to allow construction traffic to enter the undergrounding site from the local highway. You can find more information on our construction information page.
Removing a section of 132,000 volt overhead line to the east of the substation and replacing it with underground cable. This will enable the 400,000 volt overhead line to pass safely overhead.
Installing a Cable Sealing End (CSE) pylon to connect the new underground cable to the existing overhead line.