The dam at Loch Awe, which is at the foot of Ben Cruachan mountain

Inside the hollow mountain

We drive Audi’s all-new Q7 e-tron hybrid SUV right inside a mountain
to visit Cruachan Power Station in the Scottish Highlands

I love mountains. I love walking up them and I love driving through them. But I never imagined that one day I would get the chance to drive right inside one. However, that is just what’s about to happen. The massive electric steel security gate in front of me slides back and I begin easing the Audi Q7 e-tron forwards. As the SUV glides eerily through the rocky tunnel in silent electric mode, it feels like I’m sneaking into a Bond villain’s layer, or maybe about to participate in a Tom Baker-era Dr Who adventure.

The Audi Q7 on the bridge leading to Cruachan Power Station

The dam at Loch Awe

Happily, I meet no aliens attempting to repair a crashed spacecraft, nor any super-baddies plotting to blow up the planet. But what I do discover would certainly be worthy of a film, for the story of Cruachan Power Station near Oban is a truly remarkable one. Constructed between 1959 and 1965, this pumped-storage hydroelectric power station is the second largest of its kind in the UK.

But what makes this Cruachan facility so unique is that its four massive pump-turbine units – capable of producing a combined 440MW of electricity, sufficient to power a city the size of Edinburgh – are all located in a vast hall deep within Ben Cruachan. And it takes a staggering 19 miles of tunnels and aqueducts to deliver water to the pump-turbine units.

The Audi Q7 driving through the Scottish Highlands

That water comes from two sources: from Loch Awe at the foot of Ben Cruachan, and from a massive 10,000,000m3 man-made reservoir situated near the summit of the mountain. ‘At times of low demand on the National Grid, or in breezy weather when wind farms are producing excess electricity, we use it to pump water up from Loch Awe to the reservoir about 400 metres above the turbines,’ explains Ross Galbraith, Head of UK Hydro for Scottish Power. ‘Then when there is a high demand on the National Grid, we release the water stored in the reservoir and use it to power the turbines and produce electricity. With two clicks of a mouse button, we can go from rest to full power in just two minutes. Provided the top reservoir is full, we can run on full load for 14½ hours if need be.’

The head of UK Hydro for Scottish Power Ross Galbraith

Inside Cruachan Power Station

The ingenious manner in which the power station balances energy use is reminiscent of the Audi Q7 e-tron. On my 900-mile round trip to the west coast of Scotland, the hybrid SUV switches seamlessly between turbodiesel and electric power, and sometimes a combination of both – whatever is required to make the journey as efficient as possible.

Cruachan can also be called upon to perform what is known as a Black Start, which definitely sounds like something out of a Bond novel. ‘In the event of complete failure of the National Grid, you need stations that can come back on remotely and start supplying electricity to get the grid back up and running,’ reveals Ross. ‘We have a diesel generator and the station is manned 24 hours, so even if the country’s entire electricity supply is down, we can get up and running and help turn the lights back on.’

The Audi Q7 parked in the Ben Cruachan Mountain tunnel

The control desk at Cruachan Power Station

A worker at Cruachan Power Station

Cruachan Power Station Visitor Centre attracts around 50,000 tourists every year. We had to get special permission to drive our Audi Q7 e-tron into the mountain, but visitors can enjoy a bus ride through the tunnel and a guided tour of the facilities. If you pack your walking boots and don’t mind a good long hike, you can also walk up to the reservoir near the summit of Ben Cruachan. Plus there’s all that wonderful Highland scenery to drive through. It’s well worth a trip – after all, it’s not every day you get to go inside a mountain. Written by Angus Frazer. Photographs by Alex Shore.


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