National Grid has energised the second of three new high voltage electricity circuits linking Dinorwig hydroelectric power station with the transmission network in North Wales.
The company said the milestone follows the first circuit going live in January last year as part of a project to replace infrastructure installed in the 1970s between Dinorwig and Pentir substation.
National Grid added that the work, delivered with Morgan Sindall Infrastructure and Siemens Energy, aims to ensure reliable clean electricity flows from the station for decades.
The Dinorwig pumped storage station in Elidir Fawr mountain in Gwynedd provides fast-response power generation to help stabilise the transmission network.
The facility is owned and operated by First Hydro, a company 75% owned by ENGIE.
Upgrades have been underway since autumn 2021, including reinforcement works at Dinorwig substation housed within the mountain.
The upgraded substation includes a hybrid solution using SF6 and clean air gas insulated switchgear technology.
National Grid is seeking to cut SF6 emissions from its network by 50% by 2030.
Focus now turns to completing the third circuit and continuing works at Pentir and Dinorwig substations.
“Switching on the second new circuit is a major step forward for this project. We’re strengthening a vital clean energy link in North Wales and ensuring Dinorwig can continue to power homes, businesses and communities for years to come,” said Mark Brindley, construction director at National Grid.
“We’re immensely grateful for the continued patience and understanding of local communities as we push ahead with the final phase of this complex once-in-a-generation project.”
“We’re proud to be delivering this important work in North Wales, helping to bring cleaner energy onto the UK national grid and strengthen the resilience of the network. Energising the second circuit is the latest success story of strong collaboration, as we apply an innovative approach to upgrading existing circuits and boosting capacity between the Dinorwig and Pentir substations in a challenging environment,” said Peter Kirk, managing director – energy at Morgan Sindall Infrastructure.
“It is fantastic to see the second circuit energised – another important step for Dinorwig’s future and enhanced reliability. As owner and operator, ENGIE is investing to extend the life of the station and is proud to be working with partners supporting its delivery; strengthening the flow of clean, flexible power from Wales to homes across the UK,” said Delphine Cherel-Sparham, managing director of ENGIE Hydro UK.