This is an old revision of this page, as edited by Minhducthandan (talk | contribs) at 18:41, 25 July 2007 (What do you mean of SPAM?). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.
Revision as of 18:41, 25 July 2007 by Minhducthandan (talk | contribs) (What do you mean of SPAM?)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)
Small hydro is the application of hydroelectric power on a commercial scale serving a small community or medium sized industry. During 2005 small hydro installations grew by 8% to raise the total world small hydro capacity to 66 GW. Over 50% of this was in China (with 38.5 GW), followed by Japan (3.5 GW) and the United States (3 GW). China plans to electrify a further 10,000 villages by 2010 under their China Village Electrification Program using renewable energy, including further investments in small hydro and photovoltaics.
A generating capacity of up to 10 megawatts (MW) is becoming generally accepted as the upper limit of what can be termed small hydro, although this may be stretched to 25 MW and 30 MW in Canada and the USA. In contrast many hydroelectric projects are of enormous size, such as the generating plant at the Hoover Dam (2,074 megawatts) or the vast multiple projects of the Tennessee Valley Authority.
Hydroelectric power is the technology of generating electric power from the movement of water through rivers, streams, and tides. Water is fed via a channel to a turbine where it strikes the turbine blades and causes the shaft to rotate. To generate electricity the rotating shaft is connected to a generator which converts the motion of the shaft into electrical energy.
Small hydro is often developed using existing dams or through development of new dams whose primary purpose is river and lake water-level control, or irrigation. A small-scale hydroelectric facility requires a sizeable flow of water and a reasonable height of fall of water, called the head.
Small hydro can be further subdivided into mini hydro, usually defined as less than 1,000 kW, and micro hydro which is less than 100 kW. Micro hydro is usually the application of hydroelectric power sized for small communities, single families or small enterprise.
List of small installations
- Snoqualmie Falls#Power plants
- St Catherine's, a National Trust site near Windermere, Westmorland, UK.
See also
External links
- Advanced small scale hydro power
- Neo-Aerodynamic
- Scots inventor cracks centuries-old puzzle
- Small scale hydro power
- UK Small Hydro Development
References
- ^ Renewables Global Status Report 2006 Update, REN21, published 2006, accessed 2007-05-16