Hydro-electricity is electricity generated by water flowing through turbines. THe water flow can be generated through pipes dropping from a reservoir or using the natural flow of a river. With its high rainfall and steep topography Scotland is ideally placed to use the water in her rivers and lochs to drive turbines to generate electricity. Hydropower is the original renewable energy source, with the first scheme at Foyers above Loch Ness coming onstream in 1896 to power an aluminium smelting plant. The Power from the Glens campaign in the 1940s and 50s gave Scotland a reliable, large scale and green electricity supply and bought electricity to thousands of remote Highland homes
Hydro schemes are of two main types. Storage schemes use a dam to collect water in a reservoir, which allows generation when rainfall is low and river levels are dropping, while run-of-river schemes use the natural flow of the river, with the consequence that electricity output goes up and down with the flow volume. A third type of scheme, pump storage, uses cheap off-peak electricity to pump water back uphill to a top reservoir then releases this water to allow it to flow back down the hill through the turbines at times of peak demand. This third type of hydro scheme has great potential as a way of storing surplus power generated through intermittent renewables such as wind. One great advantage of all three types of system is that they can be switched on and off in minutes, making them a very useful componoent in managing variable demand.
Scotland currently has 1.4GW of hydro-electric generating capacity. There is potential for expansion, but environmental campaigners tend to object to large scale flooding of glens these days so new schemes are likely to be smaller, with a growing interest in so called “micro-hydro” projects. These small-scale developments, often run-of-river schemes, have become more viable for farmers and landowners with the introduction of the Feed-in Tariffs now available to small scale renewables projects.
|Hydro Energy Factsheet from HiEnergy|
|A basic guide to micro hydro schemes - how a typical run of river scheme works, financial and planning considerations plus a step by step guide to the initial assessment of a potential hydro scheme.|
|Pumped Storage Hydro In Scotland|
|An article discussing how pumped storage works and looking at its role as a storage medium for surplus wind-generated electricity and the capacity for future expansion.|
|Power From The Glens|
|Fascinating and detailed PDF publication from Scottish and Southern Energy detailing all the Scottish hydro installations with sections on the history and building of the schemes and their interaction with nature.|