Cruachan Power Station

Cruachan Power Station is a pumped-storage hydroelectric plant carved inside Ben Cruachan in Argyll and Bute. It stands beside Loch Awe, linked by tunnels and penstocks to a high reservoir 396 metres above. The scheme uses water moved between the loch and reservoir to store energy at night and release it by day. Only four such stations exist in the United Kingdom, and Cruachan can restart the National Grid without outside power. Construction began in 1959 and was opened by Queen Elizabeth II in 1965 after six years of work by thousands of labourers. The station’s engineering is remarkable. Four reversible turbines act as both pumps and generators, housed in a cavern 300 metres below the mountain’s surface. The turbine hall is 91.5 metres long, 23.5 metres wide and 38 metres high, with a transformer hall beside it. Water travels through 260-metre penstocks inclined at 56 degrees before splitting into four shafts. A 1-kilometre road tunnel leads to the hall, where tropical plants grow in the warm, damp air. Visitors find a visitor centre beside the outflow to Loch Awe, receiving around 50,000 tourists each year. Inside the mountain, the turbine hall and its massive machinery can be viewed, while outside the reservoir sits high above the loch. The dam wall contains the equipment to keep its appearance clean, and nearby the Falls of Cruachan railway station offers seasonal access. A modernist mural by Elizabeth Falconer lines the walls, celebrating the workers and legends tied to the mountain.