On January 7th the 200-metre-long tunnel boring machine called Eliza Jane broke through the side of a mountain in Scotland after sixteen months of grinding. The resulting five mile tunnel will take water from a reservoir up on the Monadhliath plateau down to Loch Ness, via an underground cavern housing a hydro-electric power station. It’s the biggest civil engineering project in Scotland, and the first major hydro scheme in Britain since the fifties I think. As such, it’s tremendously exciting: as I’ve mentioned before, hydro power sets me all a-trembling with fascination and a smidgin of dread. So indulge me.
The water head – the vertical distance from the turbine to the intake at the reservoir, is 600 metres, the highest in Britain. That’s just as well, because there aren’t any big rivers up there, and to get a half-decent flow they’re having to gather together a number of burns.
http://www.topomatika.hr/Applications/turbine-en.htm
The power station will use a Pelton turbine. The American Lester Allan Pelton invented it in about 1870, and it’s still going strong. It’s pretty much the most efficient way of getting the energy out of a jet of water. It works by getting energy from the force of a high-speed jet, not from the pressure of the head of water. And with a high head of 600 meteres you can get a pretty fast flow going.
We’re not about to run out of rain any time soon – any more than we’re about to run out of wind – so it’s as sustainable as you can get. Some members of the walking community were opposed to it, at least in the beginning, but it’s generally viewed favourably by environmentalists and it’s popular with the locals. (As it is, the area isn’t much frequented by walkers anyway, and it’s primarily been only a deer and grouse hunting area for a long time.) It’ll have a capacity of 100 megawatts, which is a huge contribution to the country’s energy – the equivalent of 50 wind turbines.
Scottish & Southern Energy seem to have been very careful not to disturb any important or sensitive species of wildlife. Concerning the water vole, they even went as far as to establish that the dam and reservoir will destroy only a few disused burrows. Whether the presence of a single water vole at the bottom of the valley would have stalled the project, I’m not sure.
If you can’t get enough of all this water engineering, the scheme featured in a radio program by Adam Hart-Davis a couple of years ago, when construction was just beginning. You can still listen to it here. Also, have a look at my other posts, on the Great Man-made River Project and the Loch Sloy Power Station.
BBC report
Edinburgh Evening News report
Glendoe scheme official site
I used to be a homeless rodeo clown but now I am a world class magician !