National Grid is holding a series of public information events on its proposals to reinforce and refurbish the electricity network between Pentir and Trawsfynydd.
The events run from today at venues across Gwynedd.
The existing transmission system was largely built in the 1960s and was designed to connect electricity mainly generated in coal-fired power stations to homes in Wales and England. To allow new sources of renewable energy to be connected to the network, we need to reinforce and refurbish the existing electricity network between Pentir and Trawsfynydd. This will help to keep the network secure and resilient by enabling more clean energy to be delivered to homes and businesses.
The project is part of The Great Grid Upgrade, the largest overhaul of the electricity grid in generations.
Suzanne Crouch, Portfolio Director for Pentir to Trawsfynydd, commented: “This reinforcement and refurbishment project between Pentir and Trawsfynydd is essential to carry more clean energy to homes and businesses across Wales.
“We’re looking forward to sharing our plans with communities and encourage anyone interested to come to our events.”
We currently expect construction to start in Spring 2026 for completion in spring 2029, though this is subject to obtaining the necessary planning, licences and other agreements.
The refurbishment and reinforcement work includes:
• Installing new and replacement underground cables and other equipment within the existing substation sites at Pentir and Trawsfynydd
• Constructing a new substation south of Bryncir
• Replacing one side of the overhead line between Bryncir and Trawsfynydd
• Replacing the underground cables that run beneath the Glaslyn Estuary at Porthmadog from Wern to Minffordd
• Connecting the new Glaslyn cables to the Eryri Visual Impact Provision (EVIP) project cables at Minffordd with new equipment, and removing the existing equipment nearby
The National Grid team will be on hand to discuss the project with communities at a series of public information events being held throughout May. Draft technical plans will be available to show our work in progress and our team will be happy to answer queries.
Those unable to attend an in-person event can go to an online webinar, in both Welsh and English, on Wednesday, 28 May, 6pm-7pm.
For further details on the project or to register for our webinar visit our website at: www.nationalgrid.com/electricity-transmission/network-and-infrastructure/infrastructure-projects/pentir-trawsfyndd-reinforcement-project
The first public information event is today, Friday 9 May, 4pm–7pm, at Garndolbenmaen Village Hall, Garndolbenmaen, LL51 9SQ.
Tomorrow, Saturday, 10 May, 10am-1pm*, Byw’n lach Glaslyn, Stryd Y Llan, Porthmadog LL49 9HW, host an event.
On Tuesday, 13 May, 4pm-7pm, you can attend Porthmadog FC Function Room and Conference Centre, Y Traeth, Porthmadog LL49 9PP.
On Thursday, 15 May, 4pm-7pm, go to Tremadog Memorial Institute, Market Square, Tremadog LL49 9RA, and on Tuesday, 20 May 11am-2pm*, you can go to Neuadd Goffa Penrhyndeudraeth, Griffin Terrace, Penrhyndeudraeth LL48 6LP.
* The EVIP project team will be present at the events marked with this symbol.