Major £300 Million Investment Approved for North Wales Hydro Power Stations
A significant £300 million investment has been officially approved for the Dinorwig and Ffestiniog pumped storage hydro stations in North Wales. This substantial funding forms a crucial part of a larger £1 billion investment programme initiated by the joint owners of these two plants, First Hydro Company, which is a collaborative venture between French energy giant ENGIE and investment firm La Caisse.
Historic Sites with Vital Regional Role
These hydroelectric facilities have long played an indispensable role in the local communities and across the wider region. The Ffestiniog station commenced operations in 1964, while the larger Dinorwig plant opened two decades later in 1984. The investment has received formal approval from the boards of ENGIE, which holds a 75% stake in First Hydro Company, and La Caisse.
This financial commitment will enable the first two generating units at Dinorwig to undergo comprehensive replanting and modernization. These upgraded units are projected to return to commercial operation in 2028 and 2029 respectively. Importantly, during the extensive construction period, the remaining four units at Dinorwig will continue to operate at full capacity, ensuring no disruption to energy supply.
Engineering Marvels Beneath the Mountains
Located approximately 500 metres beneath Elidir Fawr in Gwynedd, the engineering works will involve replacing major components at Dinorwig. This includes installing new turbine and generator shafts weighing around 160 tonnes each, alongside generator motor rotors that can reach up to 460 tonnes in weight.
The sheer scale of the underground cavern housing the station is remarkable, being large enough to accommodate St Paul's Cathedral. At peak output, Dinorwig can generate up to 1,800 megawatts of power, sufficient to supply electricity to approximately 1.5 million homes. Collectively, these two stations represent 5% of the United Kingdom's total installed power generation capacity and an impressive 74% of the nation's pumped storage hydro capacity.
Economic and Employment Benefits
At the peak of construction activity, this investment programme will involve more than 250 skilled workers and professionals, providing a significant boost to the local economy and employment in North Wales. ENGIE is further strengthening the talent pipeline in the region through collaborations with Bangor University and Wrexham University, as well as partnerships with Ambition Wales and the North Wales skills portal.
Broader Strategic Context
This announcement follows ENGIE's recent agreement to acquire UK Power Networks, one of Britain's largest electricity distribution companies, for an equity value of £10.5 billion. Miya Paolucci, UK chief executive of ENGIE, emphasized that "Wales plays a central role in ENGIE's UK strategy. Reaching financial close on this latest tranche of our pumped hydro investment demonstrates our long-term confidence in these vital assets and in the role flexible storage plays in the energy transition."
First Hydro Company has already invested £250 million since 2017 on replanting works at Ffestiniog and preliminary activities at Dinorwig, highlighting the ongoing commitment to these facilities.
National Grid Infrastructure Upgrades
Simultaneously, the National Grid has activated the second of three new high voltage electricity circuits connecting the Dinorwig hydroelectric power station with the transmission network in North Wales. This marks another critical step in future-proofing an essential component of Britain's energy grid.
This follows the energization of the first new circuit in January of the previous year and forms part of National Grid's comprehensive project to replace infrastructure originally installed in the 1970s between Dinorwig and Pentir substation. Since autumn 2021, National Grid, along with delivery partners Morgan Sindall Infrastructure and Siemens Energy, has been upgrading this connection to ensure clean electricity from the power station continues to flow reliably for decades to come.
Mark Brindley, construction director at National Grid, stated: "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. 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."
