There are four Francis turbines, which operate as both pumps and generators. These are housed in a cavern within Ben Cruachan, which is long, wide and high, with an adjacent transformer hall. The chamber is at a depth of around , and is located within a hard granite intrusion. Construction of the power station required the removal of of rock. Access to the hall is gained by a road tunnel long, high and wide, which is warm and humid enough to allow tropical plants to grow.