A Brief History

Using the power of water is not new, a walk along many rivers will show evidence of leats and weirs. The new aspects to water power are the current drive on renewable and sustainable technology which is developing to ease our reliance on oil, and the associated financial incentives. This increased awareness, and more targets from government, are giving schemes better chances at the planning committee stage also. Modern technology is being deployed to allow a high degree of automation, reducing the need for continuous monitoring, and hence labour costs.

Water power was a driving force behind the industrial revolution, before the advent of steam engines it was recognised as an excellent energy source. Waterwheels abounded, powering workshops (for example Finch Foundry), pumped water from mines (Morwellham Quay), ground corn (many examples), and powered the first factories. With the advent of steam power, and later electricity and the internal combustion engine, many wheels fell out of use. Waterwheels are a simple method of extracting energy from water, but to extract the energy from a drop a wheel is required which is at least equal to the size of the drop. Hence they can be very large (for example the Laxey Wheel, or Welsh Slate Museum, Llanberis), and hence can rotate exceptionally slowly. This is not ideal for modern purposes of power generation. Water supply infrastructure usually required periodic maintenance and constant supervision and the water available did not always match the requirements for use. For these reasons, and the relatively low price of fossil fuels, mills often fell into disrepair, especially as the small mills themselves became unviable.

In the late 19th century new machines emerged, the design of which are still used today in some circumstances. They were small, and ran at high speed. This lent itself to power generation, and many early power plants were built using water power (for example Chagford).

Development continued through the 20th century, but again technology allowed fossil fuels to develop much further, as they tend to fit the centralised power generation system better. Where large potentials exist they have been exploited, as extensively in Scotland and elsewhere through the UK. Many early hydro electric power stations are still in use, some with original equipment, as their high initial cost is balanced by very low ongoing costs, creating a long term solution. Pumped storage systems have been used, as at Ffestiniog and Dinorwic which help the national grid to balance supply and demand, although these are not renewable energy sources, but essentially batteries. There are now changes occurring, in terms of how the grid is managed, which are tending to encourage small scale, local generation (‘embedded’ or ‘distributed’ in the jargon), and this is where small schemes can often now fit in.