Feeds

Boffins, Tunnel Tigers and Scotland's world-first power mountain

The hollowing heroes who reversed nature

The essential guide to IT transformation

Geek's Guide to Britain In the middle of a Scottish mountain is a man-made cavern 90 metres high and 36 metres long - tall enough to stuff an entire Cathedral in its belly - which is only accessible through a kilometre-long rock tunnel. This is the home of the Cruachan Power Station.

In 1921 - with one world war down and one to go - the British government surveyed its mountains with a view to generating hydro-electric power. That survey established that Cruachan, near Oban on the west coast of Scotland, would make an ideal site for storing power - if only the technology existed to make it practical.

One world war later, the technology had arrived. Within a decade, nuclear power was generating an overnight excess in need of storage, so in 1959 they broke ground to build the world's first reversible-turbine power station, which essentially uses large amounts of water to store excess energy.

A boffin

Only boffins of this calibre could realise the dream.
Still from Cruachan, The Hollow Mountain, National Library of Scotland.

That power station now comprises an artificial loch, dammed with 200,000 tonnes of concrete and storing 7 gigawatt-hours' worth of water - 22 hours supply with a 12-hour reserve. That water drops down a sloping 305 metres into four turbines housed in the middle of the mountain, where we're allowed to visit them.

The idea is simple to explain, rather harder to realise: water falls from the loch above through turbines to generate electricity, 440MW of it at peak, but at night the same turbines are turned (using excess power) to push the water back to the top loch again, making the whole thing a huge storage battery designed to buffer between the constant generation and variable consumption of electricity.

Pylons

The outwards sign of something significant within

Not that you'd know it driving past Cruachan. The only signs that give away what lies beneath are the suspicious number of pylons - and a large sign pointing visitors towards the centre. Once you've got there, you can buy tea and cake, buy postcards and novelties, press buttons in the exhibition and board the minibus which takes visitors to the heart of the mountain.

A tunnel

Descending into the bowels of the earth, The Channel Tunnel should look like this

Cruachan's biggest problem in becoming a hydro plant was the lack of upper loch from which water could flow. The mountains had a nice valley but it drained neatly into Loch Awe, so the first order of business was to build an enormous dam. That took two years, thanks to the remote location and inclement weather, and below the dam shafts were dug at a 55° incline to ensure a smooth flow of water to the four generators below in their huge machine room. It is that scale of construction which most impresses.

Three contractors took on the project: one for the aqueducts, one for the tunnelling and one for the fitting out. Each brought in gangs of workers from around the UK, totally 1,300 men at its peak, accommodated in temporary camps which promptly became rife with drinking and gambling as the self-styled "Tunnel Tigers" relaxed in the way unique to young men whose employment involves considerable risk to limb and life.

Men placing explosives

Real men packing real explosives into the wall.
Still from Cruachan, The Hollow Mountain, National Library of Scotland

Thirty-six men died in all, 15 underground digging out the cavern and the rest in the construction of the tunnels and network of aqueducts feeding the upper loch.

There are four-and-a-half kilometres of aqueduct and more than 14km of tunnels catching rainwater from the surrounding hills. That rainwater took nine months to fill the reservoir and still contributes about 10 per cent of the power generated.

Having driven the kilometre into the mountain, visitors leave the bus and climb a short flight of steps to a sloping path past the fire system - where 20,000 gallons of water sit just in case they're ever needed. Our guide, the slightly over-enthused Ian, tells us that the system is tested twice a week, but has never been used.

From there we're led past tropical plants, carefully placed to emphasise the heat - that far underground it remains a steady 18°C - and some of the tools used to dig out the caverns.

Gartner critical capabilities for enterprise endpoint backup

More from The Register

next story
Boffins attempt to prove the UNIVERSE IS JUST A HOLOGRAM
Is this the real life? Is this just fantasy?
Our LOHAN spaceplane ballocket Kickstarter climbs through £8000
Through 25 per cent but more is needed: Get your UNIQUE rewards!
China building SUPERSONIC SUBMARINE that travels in a BUBBLE
Shanghai to San Fran in two hours would be a trick, though
LOHAN tunes into ultra long range radio
And verily, Vultures shall speak status unto distant receivers
SpaceX prototype rocket EXPLODES over Texas. 'Tricky' biz, says Elon Musk
No injuries or near injuries. Flight stayed in designated area
Galileo, Galileo! Galileo, Galileo! Galileo fit to go. Magnifico
I'm just a poor boy, nobody loves me. But at least I can find my way with ESA GPS by 2017
Astronomers scramble for obs on new comet
Amateur gets fifth confirmed discovery
prev story

Whitepapers

Best practices for enterprise data
Discussing how technology providers have innovated in order to solve new challenges, creating a new framework for enterprise data.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Advanced data protection for your virtualized environments
Find a natural fit for optimizing protection for the often resource-constrained data protection process found in virtual environments.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?