Drax submits application to expand Cruachan ‘hollow mountain’ power station

Renewable energy firm Drax has applied for planning consent to more than double the electricity generating capacity at its Cruachan facility in Scotland.

The new underground pumped storage hydro power station of up to 600MW, Cruachan Two, would be located inside Ben Cruachan – Argyll’s highest mountain – and increase the site’s total capacity to 1.04GW. If approved, it could be operational in 2030.

The new plant will use reversible turbines to pump water from Loch Awe to the upper reservoir on the mountainside and store excess power from wind farms and other low carbon technologies when supply outstrips demand and then use this stored water to generate renewable power when it is needed.

Around two million tonnes of rock will be excavated to create a new, hollowed-out cavern large enough to fit Big Ben on its side as well as adjoining tunnels to house the facility.

The development – which could be the first newly constructed plant of its kind in the UK in more than 40 years – will potentially support around 900 jobs during six years of construction across a range of industries from quarrying and engineering, to transport and hospitality. Around 150 on-site local construction jobs will be created during the development.

Ready to move mountains

According to Claire Mack, Scottish Renewables chief executive, pumped storage hydro is a critical technology needed to meet net zero.

“Over the last decade we have managed to develop the technologies to decarbonise the power system such as wind and solar, but what we really need now is greater flexibility to fully optimise those technologies,” she said.

“That’s why the success of long-duration storage projects such as Cruachan Two is absolutely vital to Scotland and the whole of the UK.”

In order to deploy this technology, however, Drax must secure consent under Section 36 of the Electricity Act 1989 from the Scottish Government – a process which will take around one year to complete from the application’s submission.

Alongside a successful Section 36 application, the project will also require an updated policy and market support mechanism from the UK Government.

The existing lack of a framework for long-duration electricity storage and flexibility technologies means that private investment cannot currently be secured in new pumped storage hydro projects, with no new plants built anywhere in the UK since 1984 despite their critical role in decarbonisation.

According to Ian Kinnaird, Drax’s Scottish assets director, the plan to expand Cruachan will strengthen the UK’s energy security by enabling more homegrown renewable electricity to come online and power homes and businesses across the country – helping to end reliance on imports and cut costs.

“This major infrastructure project will support hundreds of jobs and provide a real boost to the Scottish economy,” he added. “Only by investing in long-duration storage technologies can the UK reach its full renewable potential, and Drax is ready to move mountains to do just that.”

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