‘Hollow Mountain’ Cruachan Power Station set for £1M upgrade

Drax Group’s iconic Cruachan Power Station, a hydroelectric pumped storage plant built inside a hollowed-out mountain, is to undergo a £1million upgrade to modernise its turbine control system.

Employees working inside power station Where: Cruachan, Scotland

The upgrade will see the station’s current programmable logic controller (PLC) computer system replaced with a new design to put the station at the cutting edge of energy technology to improve Cruachan’s efficiency. World-leading control system builders ITI will undertake the design, installation and commissioning of the upgrade across the station’s four units.

Cruachan plays a critical role in stabilising the country’s electricity system throughout the Covid-19 pandemic due to its flexibility. The plant can generate power in less than a minute when needed and can also store excess electricity from the grid like a giant battery, a service which was called upon when the low electricity demand during the lockdown coincided with periods of high wind power in Scotland.

The plant’s reversible turbines pump water from Loch Awe to an upper reservoir on the mountainside to store excess power from the grid. The stored water is then released back through the turbines to generate power quickly and reliably when demand increases. In July, Cruachan became the first power station in Britain to provide critical system support services to the National Grid as part of a world-first stability contract aimed at reducing the threat of blackouts.

Ian Kinnaird, Drax Group’s Head of Hydro, said:

“Cruachan plays a critical role in supporting renewable energy in Scotland and stabilising the electricity grid.

“As the country continues to decarbonise, the station’s flexibility has never been more important. This upgrade will ensure the Hollow Mountain can deliver the fast, flexible power that hundreds of thousands of homes and businesses rely on for many decades to come.”

Control room operator at Cruachan Power Station

ITI has a long history with Cruachan and the other hydro assets which Drax owns and operates in Scotland. ITI is the new name for Servelec Controls, the systems integration experts who installed the current PLC control systems in 1987 and built the control system which allows the Lanark and Galloway Hydro Schemes to be remotely managed when needed from Cruachan’s underground cavern from a single interface.

Bryn Thomas, Sales Director for Power and Infrastructure at ITI said:

We’ve been working at Cruachan Power Station for over 30 years now, and in that time have developed a deep understanding of their assets, their systems and their operational requirements. It is these strong relationships with our customers that enable us to work with them on developing transformative solutions that enhance their operations, improve safety and support sustainable green energy production.”


Notes to editors

The three-year project will be run by a team of highly qualified and experienced engineers based out of ITI’s Glasgow office. The office is currently operating with strict social distancing and hygiene measures in place to allow the critical engineers to progress the project while their colleagues continue to safely work remotely, from home.

For more information visit www.drax.com/uk

Media contacts:

Aidan Kerr
Drax Group Media Manager
E: [email protected]
T: 07849 090 368

Stephanie Windmill
Head of Marketing
E: [email protected]
T: 07973 827360

About ITI

Originally formed in 1972, ITI, formerly Servelec Controls, is one of the leading independent systems integrators in the UK. From offices in Sheffield, Aberdeen, Glasgow and Warrington, it delivers on a local level, to leading owner operators in the oil and gas, renewables, power, infrastructure and defence industries.

About Drax

Drax Group’s purpose is to enable a zero carbon, lower cost energy future and in 2019 announced a world-leading ambition to be carbon negative by 2030, using Bioenergy with Carbon Capture and Storage (BECCS) technology.

Its 2,900-strong employees operate across three principal areas of activity – electricity generation, electricity sales to business customers and compressed wood pellet production.

Power generation:

Drax owns and operates a portfolio of flexible, low carbon and renewable electricity generation assets across Britain. The assets include the UK’s largest power station, based at Selby, North Yorkshire, which supplies five percent of the country’s electricity needs.

Having converted two thirds of Drax Power Station to use sustainable biomass instead of coal it has become the UK’s biggest renewable power generator and the largest decarbonisation project in Europe. It is also where Drax is piloting the groundbreaking negative emissions technology BECCS within its CCUS (Carbon Capture Utilisation and Storage) Incubation Area.

Its pumped storage, hydro and energy from waste assets in Scotland include Cruachan Power Station – a flexible pumped storage facility within the hollowed-out mountain Ben Cruachan.  It also owns and operates four gas power stations in England.


Through its two B2B energy supply brands, Haven Power and Opus Energy, Drax supplies energy to 250,000 businesses across England, Scotland and Wales.

Pellet production:

Drax owns and operates three pellet mills in the US South which manufacture compressed wood pellets (biomass) produced from sustainably managed working forests. These pellet mills supply around 20% of the biomass used by Drax Power Station in North Yorkshire to generate flexible, renewable power for the UK’s homes and businesses.

For more information visit www.drax.com/uk