Tuesday, 1 December 2009

Small scale hydroelectic schemes work

As someone who really is concerned about the environment and how we have the ability to mess it up it might seem strange that I am less than convinced that we should have massive wind farms all over the countryside. It's where I part company with 'Friends of the Earth' and other 'green' organisations of similar mind who think that anything to which you can attach a label that says "renewable" has to be supported no matter what. I can't go along with that outlook I'm afraid.

One particular renewable I've been enthusiastic about for a very long time however is that of small scale water power. I'm very pleased that on the BBC news website you can read here and here about how a Welsh hill farmer is utilising the energy of a fast flowing stream on his land to provide power some of which at least can go into the National Grid and give him a useful extra income. The thing is that we have huge numbers of streams and small rivers, not to mention long pipelines of water from reservoirs, all of which have the potential to turn turbines or Archimedes Screws to generate electricity. This is an absolutely classic instance of "small is beautiful" as they say - two massive plusses of these schemes are (1) that the generating equipment is compact and unobtrusive and hence is not blighting the landscape, and (2) by having these small schemes close to the user the huge power losses resulting from electricity being carried over huge distances from the large traditional power stations exist to a far far lesser extent.

OK I'm realistic enough to understand that such sources of power can only supply a little of our needs but the technology is well proved. The water used is only borrowed for goodness sake so, unlike fossil fuels which go on getting depleted, the water will continue to be available. It's not only in the Welsh hills that this potential exists: I understand that there is a river (or maybe more than one) in South Somerset from which numerous waterwheels for mills obtained their power. A number of these are in a scheme whereby the old water wheels have been replaced powerwise by modern turbines. So there is proved potential in the lowlands as well.

In my neck of the woods there is an interesting example of water power usage which dates in fact to before the Second World War. The water is taken from the River Tavy, one of England's fastest flowing rivers. The engineers utilised some existing leats originally used for mining purposes and built a small power station at Mary Tavy just off the western edge of Dartmoor. Later, down in Tavistock, some of the Tavy's water goes into the Tavistock Canal (a feature again resulting from the old mining boom). Terminating high above the old port of Morwellham the water is now diverted down a pipe into another hydro electric plant on the Devon bank of the Tamar.

The middle Tamar Valley was home to many leats in its industrial heyday as was Dartmoor as I hinted at in my last paragraph. Why can't the powers that be see the immense potential inland waterways and pipelines could have in generating electricity. A large part of the answer I'm sure is that each of the small schemes I enthuse about is exactly what I've said - "small". Unlike the wind energy people who no doubt are very powerful lobbyists in the corridors of power there is no one really to bend the ear of a Minister for the little projects which in total could add up to a lot.

Just one other example I'll mention here and that is one of my favourite locations - the twin villages of Lynton and Lynmouth on Devon's north coast. The West Lyn river drops rapidly off Exmoor to join its sister the East Lyn at, unsurprisingly, Lynmouth. In its short course the West Lyn not only powers a hydro electric station but also provides the means by which the steep cliff railway linking the two villages functions.

That's proper green energy for you!

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