Cruachan Underground Power Station

At current capacity, the Drax 440MW Cruachan Pumped Storage Hydro Power Station in Scotland can provide enough clean hydroelectric power for more than 500,000 homes. Using pump storage hydro, the facility provides flexible, responsive power generation from its “Hollow Mountain” power station deep within Ben Cruachan.

When Drax saw potential to expand generating capacity by 600MW, Stantec’s environmental, planning and engineering design teams provided support. Our teams engaged with primary stakeholders, including Network Rail, Transport Scotland, local authorities, the Renewables Alliance, and the public to showcase the plan — which helps meet net zero targets while enhancing domestic energy security. The public consultation enjoyed a high level of engagement from local residents, for many of whom the original Cruachan power station is a source of local pride.

We developed the concept and feasibility design for the 600MW expansion, with a plan for a new underground power cavern complex, associated 7km of tunnels up to 7.5m diameter, 1.4km of shafts and new intake and lower control works at the upper and lower reservoirs. 

The project successfully gained consent from the Scottish Government in 2023, and with the right support and appropriate regulatory framework (among other considerations), aims to link to the National Grid in 2030.