Feeds

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

The hollowing heroes who reversed nature

Top 5 reasons to deploy VMware with Tegile

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.

Security for virtualized datacentres

More from The Register

next story
Voyager 1 now EIGHTEEN LIGHT HOURS from home
Almost 20 BEEELION kilometres from Sol
Ex-Soviet engines fingered after Antares ROCKET launch BLAST
Speculation rife, but Orbital claims it's too early to tell
MEN: For pity's sake SLEEP with LOTS of WOMEN - and avoid Prostate Cancer
And, um, don't sleep with other men. If that's what worries you
Jim Beam me up, Scotty! WHISKY from SPAAACE returns to Earth
They're insured for $1m, before you thirsty folks make plans
ROGUE SAIL BOAT blocks SPACE STATION PODULE blastoff
Er, we think our ISS launch beats your fishing expedition
NASA: Spacecraft crash site FOUND ON MOON RIM
'What fun!' exlaims NASA boffin who found the LADEE
Comet Siding Spring revealed as flying molehill
Hiding from this space pimple isn't going to do humanity's reputation any good
BAE points electromagnetic projectile at US Army
Railguns for 'Future fighting vehicle'
prev story

Whitepapers

Why and how to choose the right cloud vendor
The benefits of cloud-based storage in your processes. Eliminate onsite, disk-based backup and archiving in favor of cloud-based data protection.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Saudi Petroleum chooses Tegile storage solution
A storage solution that addresses company growth and performance for business-critical applications of caseware archive and search along with other key operational systems.
Simplify SSL certificate management across the enterprise
Simple steps to take control of SSL across the enterprise, and recommendations for a management platform for full visibility and single-point of control for these Certificates.