Renewable energy company Drax has announced a £80 million investment to refurbish its Cruachan pumped storage hydro power station in Scotland.
Drax has appointed global hydropower technology supplier ANDRITZ, which has previously installed approximately 470GW of capacity, as the main contractor for the Cruachan upgrade project.
The £80 million project will see the generating capacity of two of the plant’s four units increased by a combined 40MW to raise the facility’s total generating capacity to 480MW.
Site works will commence in 2025, with ANDRITZ to install new main inlet valves and then unitised outages in 2026 and 2027 for units 3 and 4, respectively.
Pumped storage plants act like large water batteries, using reversible turbines to pump water from a lower reservoir to an upper reservoir, which stores excess power from sources such as wind farms when supply outstrips demand.
These same turbines are then reversed to bring the stored water back through the plant to generate power when the country needs it.
Drax’s investment is underpinned by the award of a 15-year capacity market agreement worth around £221 million.
The Cruachan upgrade project is separate from Drax’s plan to build a new 600MW pumped storage power station adjacent to the existing Cruachan facility; no investment decision has been made, and development remains subject to an appropriate regulatory framework.
The Cruachan site received development consent from the Scottish government in December 2023 and was awarded a capacity market agreement by the UK government in February 2024.
Drax’s interim COO, Penny Small, said: “Pumped storage hydro is vital to the UK’s energy security; it’s a technology which works in partnership with renewables.
“These plants play a critical role in stabilising the electricity system, helping to balance supply and demand through storing excess power. When wind turbines are generating more power than we need, Cruachan steps in to store the renewable electricity so it doesn’t go to waste.”
Managing director at ANDRITZ HYDRO Germany, Dominik Fust, said: “We are proud to have been entrusted with the refurbishment of the Cruachan Pump Storage Power Plant. This project aligns with our mission to contribute to the global transition toward sustainable energy generation.”
The UK’s pumped storage hydro power
Considering hydro power storage can use excess power from wind farms, Scotland is a prime location for its development, given the country’s wind portfolio and natural abundance of wind.
Therefore, it is no surprise that this is not the first project set up in the UK’s northern nation, with Norwegian energy firm Statkraft set to acquire a 450MW pumped storage hydro project being developed near Loch Ness in Scotland.
Statkraft announced that it has secured the Red John Pumped Storage Hydro Scheme from Intelligent Land Investments Group (ILI), a clean energy development company based in Hamilton, Scotland, in December 2023.
Red John, which is being developed approximately 14km southwest of Inverness, a city located in the Scottish Highlands, was first conceived in 2015 and granted consent by the Scottish government in June 2021.
England has not been completely left out, however, with long-duration ‘hydro-energy storage’ developer RheEnergise having agreed to build its first-of-a-kind system demonstrator at Sibelco’s mining operations at Cornwood, near Plymouth.
Mining company Sibelco’s Cornwood site produces kaolin, mainly for sanitary ware, ceramics, tiles and industrial applications. RheEnergise’s 500kW so-called ‘high-density’ pumped hydro energy storage (PHES) project will support the organisation in decarbonising its operation.
It is worth noting that Stephen Crosher, chief executive of RheEnergise, aims to have the “first 10MW grid-scale project in operation within two years”.
The project is being supported via the UK government’s Longer Duration Energy Storage (LODES) Demonstration Programme, and Devon County Council has provided permission for its development.
