Hydroelectric dam in cross section

The upper reservoir and dam of the Ffestiniog Pumped-Storage Scheme in north Wales.The power station at the lower reservoir has four water turbines which can generate 360 megawatts of electricity within 60 seconds of the need arising. The water of the upper reservoir (Llyn Stylan) can just be glimpsed on the right.

Hydroelectricity is a form of hydropower used to produce electricity. Most hydroelectric power comes from the potential energy of dammed water driving a water turbine and generator. Less common variations make use of water's kinetic energy or undammed sources such as tidal power. Hydroelectricity is a renewable energy source. Image File history File links Hydroelectric_dam. ... Image File history File links Hydroelectric_dam. ... The upper reservoir (Llyn Stwlan) and dam of the Ffestiniog Pumped Storage Scheme in north Wales. ... The upper reservoir (Llyn Stwlan) and dam of the Ffestiniog Pumped Storage Scheme in north Wales. ... This article does not cite its references or sources. ... Hydraulic turbine and electrical generator. ... Electricity is a general term applied to phenomena involving a fundamental property of matter called an electric charge. ... Potential energy is stored energy. ... Scrivener Dam, in Canberra, Australia, was engineered to withstand a once-in-5000-years flood event A dam is a barrier across flowing water that obstructs, directs or retards the flow, often creating a reservoir, lake or impoundment. ... Kaplan turbine and electrical generator cut-away view. ... An electrical generator is a device that produces electrical energy from a mechanical energy source. ... Kinetic energy is energy that a body has as a result of its speed. ... Tidal power is a means of electricity generation achieved by capturing the energy contained in moving water mass due to tides. ... Renewable energy (sources) or RES capture their energy from existing flows of energy, from on-going natural processes, such as sunshine, wind, flowing water, biological processes, and geothermal heat flows. ...

The energy extracted from water depends not only on the volume but on the difference in height between the source and the water's outflow. This height difference is called the head. The amount of potential energy in water is directly proportional to the head. For this reason, it is advantageous to build dams as high as possible to produce the maximum electrical energy. In fluid dynamics, head refers to the constant right hand side in the incompressible steady version of Bernoullis equation. ... Potential energy is stored energy. ... This article is about proportionality, the mathematical relation. ...

While many hydroelectric schemes supply public electricity networks, some projects were created for private commercial purposes. For example, aluminium processing requires substantial amounts of electricity, and in Britain's Scottish Highlands there are examples at Kinlochleven and Lochaber, designed and constructed during the early years of the 20th century. Similarly, the 'van Blommestein' lake, dam and power station were constructed in Suriname to provide electricity for the Alcoa aluminium industry. General Name, Symbol, Number aluminium, Al, 13 Chemical series poor metals Group, Period, Block 13, 3, p Appearance silvery Atomic mass 26. ... The Scottish Highlands are the mountainous regions of Scotland north and west of the Highland Boundary Fault. ... Kinlochleven is a village in Scotland and lies at the eastern end of Loch Leven, a sea loch cutting into the western Scottish Highlands. ... Lochaber (Scottish Gaelic, Loch Abar) refers to a large area of the central and western Scottish Highlands. ... The backbone of Surinames economy is the export of alumina and small amounts of aluminum produced from bauxite mined in the country. ... Alcoa NYSE: AA is the world’s leading producer of primary and fabricated aluminum, and alumina with operations in 43 countries. ...

In most parts of Canada (the provinces of British Columbia, Manitoba, Ontario, Quebec and Newfoundland and Labrador) hydroelectricity is used so extensively that the word "hydro" is used to refer to any electricity delivered by a power utility. The government-run power utilities in these provinces are called BC Hydro, Manitoba Hydro, Hydro One (formerly "Ontario Hydro"), Hydro-Québec and Newfoundland and Labrador Hydro respectively. Hydro-Québec is the world's largest hydroelectric generating company, with a total installed capacity (2005) of 31,512 MW Motto: Splendor Sine Occasu (Splendour without diminishment) Other Canadian provinces and territories Capital Victoria Largest city Vancouver Lieutenant-Governor Iona Campagnolo Premier Gordon Campbell (BC Liberal) Area 944,735 km² (5th) • Land 925,186 km² • Water 19,549 km² (2. ... Motto: Gloriosus et Liber (Glorious and free) Other Canadian provinces and territories Capital Winnipeg Largest city Winnipeg Lieutenant-Governor John Harvard Premier Gary Doer (NDP) Area 647,797 km² (8th) • Land 553,556 km² • Water 64,241 km² (14. ... Motto: Ut Incepit Fidelis Sic Permanet (Loyal she began, loyal she remains) Other Canadian provinces and territories Capital Toronto Largest city Toronto Lieutenant-Governor James K. Bartleman Premier Dalton McGuinty (Liberal) Area 1,076,395 km² (4th) • Land 917,741 km² • Water 158,654 km² (14. ... The first European explorer of what is now Quebec was Jacques Cartier, who planted a cross either in the Gaspé in 1534 or at Old Fort Bay on the Lower North Shore and sailed into the St. ... Motto: Quaerite Prime Regnum Dei (Seek ye first the kingdom of God) Other Canadian provinces and territories Capital St. ... Electricity is a general term applied to phenomena involving a fundamental property of matter called an electric charge. ... BC Hydro is a public utility that is the major provider of electricity in British Columbia, Canada. ... Founded in 1961, Manitoba Hydro is the electric power and natural gas utility in the province of Manitoba, Canada. ... Hydro One Incorporated delivers electricity across the Canadian province of Ontario. ... Hydro-Québec headquarters in downtown Montreal, with logo Hydro-Québec is a government-owned corporation that provides hydroelectric power for Quebec, Canada. ... In 1975 the Newfoundland and Labrador Power Commission, a crown coporation originally established to assist in rural electrification, was renamed Newfoundland and Labrador Hydro Corporation (Hydro). ... 2005 (MMV) is a common year starting on Saturday of the Gregorian calendar. ...

Importance

Hydroelectric power, using the potential energy of rivers, now supplies 20% of world electricity. Norway produces virtually all of its electricity from hydro, while Iceland produces 83% of its requirements (2004), Austria produces 67 % of all electricity generated in the country from hydro (over 70 % of its requirements). Canada is the world's largest producer of hydro power and produces over 70% of its electricity from hydroelectric sources. 2004 is a leap year starting on Thursday of the Gregorian calendar. ...

Apart from a few countries with an abundance of it, hydro capacity is normally applied to peak-load demand, because it can be readily stored during off-peak hours (in fact, pumped-storage hydroelectric reservoirs are sometimes used to store electricity produced by thermal plants for use during peak hours). It is not a major option for the future in the developed countries because most major sites in these countries having potential for harnessing gravity in this way are either being exploited already or are unavailable for other reasons such as environmental considerations. Diagram of the TVA pumped storage facility at Racoon Mountain Pumped storage hydroelectricity is a method of storing and producing electricity to supply high peak demands by moving water between reservoirs at different elevations. ...

Advantages and disadvantages

House flooded since 1955, revealed following prolonged dry weather

The chief advantage of hydro systems is elimination of the cost of fuel. Hydroelectric plants are immune to price increases for fossil fuels such as oil, natural gas or coal, and do not require imported fuel. Hydroelectric plants tend to have longer lives than fuel-fired generation, with some plants now in service having been built 50 to 100 years ago. Labor cost also tends to be low since plants are generally heavily automated and have few personnel on site during normal operation. Image File history File links Download high resolution version (1024x768, 161 KB) Summary Photograph of Upper Glendevon Reservoir, Fife, Scotland. ... Image File history File links Download high resolution version (1024x768, 161 KB) Summary Photograph of Upper Glendevon Reservoir, Fife, Scotland. ... Oil is a generic term for organic liquids that are not miscible with water. ... Natural gas (commonly refered to as gas in many countries, but note that gas is also an American and Canadian shortening of gasoline) is a gaseous fossil fuel consisting primarily of methane. ... Coal is a fossil fuel extracted from the ground by deep mining, coal mining (open-pit mining or strip mining). ...

Hydroelectric plants generally have small to negligible emissions of carbon dioxide and methane due to reservoir emissions, and emit no sulfur dioxide, nitrogen oxides, dust, or other pollutants associated with combustion. Since the generating units can be started and stopped quickly, they can follow system loads efficiently, and may be able to reshape water flows to more closely match daily and seasonal system energy demands. Hydroelectric plants with reliable hydrological histories are dispatchable and can be considered firm capacity. Consequently, in normal water years hydroelectric plants designed for a firm load will have a useful amount of surplus energy that may be exportable if transmission is available. Carbon dioxide is an atmospheric gas comprised of one carbon and two oxygen atoms. ... R-phrases S-phrases , , , Flash point −188 °C Autoignition temperature 537 °C Explosive limits 5–15% Supplementary data page Structure and properties n, εr, etc. ... Sulfur dioxide (or Sulphur dioxide) has the chemical formula SO2. ... Dust is a general name for minute solid particles of diameters less than 500 micrometers (otherwise see sand or granulates) and, more generally, for finely divided matter. ...

Pumped storage plants currently provide the most significant means of storage of energy on a scale useful for a utility, allowing low-value generation in off-peak times (which occurs because fossil-fuel plants cannot be entirely shut down on a daily basis) to be used to store water that can be released during high load daily peaks. Operation of pumped-storage plants improves the daily load factor of the generation system. Diagram of the TVA pumped storage facility at Racoon Mountain Pumped storage hydroelectricity is a method of storing and producing electricity to supply high peak demands by moving water between reservoirs at different elevations. ... Load Factor (LF) – The percentage of seats filled. ...

Reservoirs created by hydroelectric schemes often provide excellent leisure facilities for water sports, and become tourist attractions in themselves. Multi-use dams installed for irrigation, flood control, or recreation, may have a hydroelectric plant added with relatively low construction cost, providing a useful revenue stream to offset the cost of dam operation. There are a large number of sports that involve water. ...

In practice, the utilization of stored water is sometimes complicated by demand for irrigation which may occur out of phase with peak electricity demand. Times of drought can cause severe problems, since water replenishment rates may not keep up with desired usage rates. Minimum discharge requirements represent an efficiency loss for the station if it is uneconomic to install a small turbine unit for that flow. High-altitude aerial view of irrigation in the Heart of the Sahara Irrigation (in agriculture) is the replacement or supplementation of rainfall with water from another source in order to grow crops. ...

Concerns have been raised by environmentalists that large hydroelectric projects might be disruptive to surrounding aquatic ecosystems. For instance, studies have shown that dams along the Atlantic and Pacific coasts of North America have reduced salmon populations by preventing access to spawning grounds upstream, even though most dams in salmon habitat have fish ladders installed. Salmon smolt are also harmed on their migration to sea when they must pass through turbines. This has led to some areas barging smolt downstream during parts of the year. Turbine and power-plant designs that are easier on aquatic life are an active area of research. Environmentalist is a person or a group that supports any goal of the environmental movement. ... In ecology, an ecosystem is a naturally occurring assemblage of organisms (plant, animal and other living organisms—also referred to as a biotic community or biocoenosis) living together with their environment (or biotope), functioning as a loose unit. ... The Atlantic Ocean is Earths second-largest ocean, covering approximately one_fifth of its surface. ... For other meanings of Pacific, see Pacific (disambiguation). ... World map showing North America A satellite composite image of North America North America is a continent in the northern hemisphere bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the south by the Caribbean Sea, and on the west by the... The Chinook or King Salmon is the largest salmon in North America and can grow up to 58 long and 126 pounds. ... Frog spawn Spawning is the production or depositing of eggs in large numbers by aquatic animals. ... Pool-and-weir fish ladder at Bonneville Dam on the Columbia River Fishways, most commonly referred to as fish ladders but also known as fish passes, are structures placed on or around man-made barriers (such as dams and weirs) to assist the natural migration of diadromous fishes. ... A young salmon at the stage intermediate between the parr and the grilse, when it becomes covered with silvery scales and first migrates from fresh water to the sea. ... Kaplan turbine and electrical generator cut-away view. ... Self propelled barge carrying bulk crushed stone A barge is a flat-bottomed boat, built mainly for river and canal transport of heavy goods. ...

Generation of hydroelectric power can also have an impact on the downstream river environment. First, water exiting a turbine usually contains very little suspended sediment, which can lead to scouring of river beds and loss of riverbanks. Second, since turbines are often opened intermittently, rapid or even daily fluctuations in river flow are observed. In the Grand Canyon, the daily cyclic flow variation caused by Glen Canyon Dam was found to be contributing to erosion of sand bars. Dissolved oxygen content of the water may change from preceding conditions. Finally, water exiting from turbines is typically much colder than the pre-dam water, which can change aquatic faunal populations, including endangered species. The Grand Canyon is a colorful, steep-sided gorge, carved by the Colorado River, in northern Arizona, USA. The canyon appears on many versions of the Seven Natural Wonders of the World list, although none of these lists are by any means authoritative. ... Glen Canyon Dam Glen Canyon Dam is a dam on the Colorado River at Page, Arizona. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Chalcogens Group, Period, Block 16, 2, p Appearance colorless Atomic mass 15. ... The American bison numbered as few as 750 in 1890 due to extreme overhunting. ...

The reservoirs of hydroelectric power plants in tropical regions may produce substantial amounts of methane and carbon dioxide. This is due to plant material in newly flooded and re-flooded areas being inundated with water, decaying in an anaerobic environment, and forming methane, a very potent greenhouse gas. The methane is released into the atmosphere once the water is discharged from the dam and turns the turbines. According to the World Commission on Dams report, where the reservoir is large compared to the generating capacity (less than 100 watts per square metre of surface area) and no clearing of the forests in the area was undertaken prior to impoundment of the reservoir, greenhouse gas emissions from the reservoir may be higher than those of a conventional oil-fired thermal generation plant [1]. In boreal reservoirs of Canada and Northern Europe, however, greenhouse gas emissions are typically only 2 to 8 percent of any kind of conventional thermal generation. R-phrases S-phrases , , , Flash point −188 °C Autoignition temperature 537 °C Explosive limits 5–15% Supplementary data page Structure and properties n, εr, etc. ... Carbon dioxide is an atmospheric gas comprised of one carbon and two oxygen atoms. ... Top: Increasing atmospheric CO2 levels as measured in the atmosphere and ice cores. ... Boreal means northern from the eponymous Boreas, god of the North Wind in Greek mythology. ...

Another disadvantage of hydroelectric dams is the need to relocate the people living where the reservoirs are planned. In many cases, no amount of compensation can replace ancestral and cultural attachments to places that have spiritual value to the displaced population. Additionally, historically and culturally important sites can be lost, such as the Three Gorges Dam project in China, the Clyde Dam in New Zealand and the Ilisu Dam in Southeastern Turkey. The Three Gorges Dam (Chinese: 三峡大坝; pinyin: ) spans the Yangtze River (the third longest river in the world) at Sandouping, Yichang, Hubei province, China. ... The Clyde Dam The Clyde Dam is New Zealands largest hydroelectric dam and was built along the Clutha River, near the town of Clyde. ... Ilisu Dam is one of the 21 dams of the Southeastern Anatolia Project of Turkey. ...

Some hydroelectric projects also utilize canals, typically to divert a river at a shallower gradient to increase the head of the scheme. In some cases, the entire river may be diverted leaving a dry riverbed. Examples include the Tekapo and Pukaki Rivers. The Canal du Midi in Toulouse, France Canals are man-made waterways, usually connecting existing lakes, rivers, or oceans. ... The Tekapo River flows through the Mackenzie Basin, Canterbury, in New Zealands South Island. ... The Bukaki River flows through the Mackenzie Basin, Canterbury, in New Zealands South Island. ...

Hydro-electric facts

Oldest

• Cragside, Rothbury, England completed 1870, Water commercial service at Minneapolis.
• Duck Reach, Launceston, Tasmania. Completed 1895. The first publicly-owned hydro-electric plant in the Southern Hemisphere. Supplied power to the city of Launceston for street lighting.
• Decew Falls 1, St. Catharines, Ontario, Canada completed 25 August 1898. Owned by Ontario Power Generation. Four units are still operational. Recognised as an IEEE Milestone in Electrical Engineering & Computing by the IEEE Executive Committee in 2002.

Cragside is a country house near Rothbury in Northumberland, England. ... Rothbury is a town in Northumberland, England, located on the River Coquet near the Simonside Hills and the Northumberland National Park. ... Wikimedia Commons has media related to: England Inter. ... 1870 was a common year starting on Saturday (see link for calendar). ... This article is about the city in Minnesota. ... Duck Reach Power Station was the first publicly-owned hydro-electric plant in the Southern Hemisphere, and provided the Tasmanian city of Launceston with hydro-electric power from its construction in 1895 to its closure in 1955. ... St. ... Motto: Ut Incepit Fidelis Sic Permanet (Loyal she began, loyal she remains) Other Canadian provinces and territories Capital Toronto Largest city Toronto Lieutenant-Governor James K. Bartleman Premier Dalton McGuinty (Liberal) Area 1,076,395 km² (4th) • Land 917,741 km² • Water 158,654 km² (14. ... Ontario Power Generation (OPG) is a public company whose shares are wholly owned by the government of Ontario. ... The Institute of Electrical and Electronics Engineers or IEEE (pronounced as eye-triple-ee) is an international non-profit, professional organization incorporated in the State of New York, United States. ...

Largest hydro-electric power stations

Itaipu Dam

The La Grande Complex in Quebec, Canada, is the world's largest hydroelectric generating system. The eight generating stations of the complex have a total generating capacity of 16,021 MW. The Robert-Bourassa station alone has a capacity of 5,616 MW. A nineth station (Eastmain-1) is currently under construction and will add 480 MW to the total. An additional project on the Rupert River, currently undergoing environmental assessments, would add two stations with a combined capacity of 888 MW. Itaipu Dam File links The following pages link to this file: Electricity generation Itaipu Hydroelectricity ... Itaipu Dam File links The following pages link to this file: Electricity generation Itaipu Hydroelectricity ... La Grande River is a river in northwestern Quebec which rises in the highlands of north central Quebec and flows roughly 900 km west to drain into James Bay. ... The first European explorer of what is now Quebec was Jacques Cartier, who planted a cross either in the Gaspé in 1534 or at Old Fort Bay on the Lower North Shore and sailed into the St. ...

Fully operational

These are ranked by maximum power. Itaipu Dam Itaipu (Guarani: Itaipú; pronounced ) is a dam that includes the largest hydroelectric power plant in the world. ... The Guri Dam is one of the biggest in the world. ... Grand Coulee Dam Grand Coulee Dam is a hydroelectric gravity dam on the Columbia River in Washington State, built by industrialist Henry J. Kaiser. ... Енисей Length 5,550 (4,102) km Elevation of the source  m Average discharge 19,600 m³/s Area watershed 2,580,000 km² Origin  ? Mouth  Arctic Ocean Basin countries Russia The Yenisei basin, Lake Baikal, and the cities of Dikson, Dudinka, Turukhansk, Krasnoyarsk, Irkutsk The Yenisei (Енисе́й) is the greatest river... Churchill Falls, Labrador, Canada Churchill Falls are spectacular waterfalls, 245 ft (75 m) high, on the Churchill River in Labrador, Canada. ...

In progress

• Three Gorges Dam, China, First power July 2003,Scheduled completion, 2009, 18,200 MW

The Three Gorges Dam (Chinese: 三峡大坝; pinyin: ) spans the Yangtze River (the third longest river in the world) at Sandouping, Yichang, Hubei province, China. ... 2003 (MMIII) is a common year starting on Wednesday of the Gregorian calendar. ... 2009 by topic 2009 (MMIX) is a common year starting on Thursday of the Gregorian calendar. ...

Countries with the most hydro-electric capacity

• Canada, 341,312 GWh (66,954 MW installed)
• USA, 319,484 GWh (79,511 MW installed)
• Brazil, 285,603 GWh (57,517 MW installed)
• China, 204,300 GWh (65,000 MW installed)
• Russia, 160,500 GWh (44,000 MW installed)
• Norway, 121,824 GWh (27,528 MW installed)
• Japan, 84,500 GWh (27,229 MW installed)
• India, 82,237 GWh (22,083 MW installed)
• France, 77,500 GWh (25,335 MW installed)

These are 1999 figures and include pumped-storage hydroelectricity schemes. Diagram of the TVA pumped storage facility at Racoon Mountain Pumped storage hydroelectricity is a method of storing and producing electricity to supply high peak demands by moving water between reservoirs at different elevations. ...

References

1. New Scientist report on greenhouse gas production by hydroelectric dams.
2. International Water Power and Dam Construction Venezuela country profile
3. International Water Power and Dam Construction Canada country profile
4. Tremblay, Varfalvy, Roehm and Garneau. 2005. Greenhouse Gas Emissions - Fluxes and Processes, Springer, 732 p.

See also

Wikimedia Commons has media related to:

Hydroelectricity

• Hydropower
• List of energy topics
• Wave power
• Tital power
• List of reservoirs and dams
• Tennessee Valley Authority
• Small hydro
• Pumped-storage hydroelectricity
• Environmental concerns with electricity generation
• William George Armstrong, 1st Baron Armstrong an early private hydro-electric station

Image File history File links Commons-logo. ... The Wikimedia Commons (also called Commons or Wikicommons) is a repository of free content images, sound and other multimedia files. ... Hydraulic turbine and electrical generator. ... This list identifies articles and categories that relate to energy. ... When an object bobs up and down on a ripple in a pond, it experiences an elliptical trajectory. ... Tidal power is a means of electricity generation achieved by capturing the energy contained in moving water mass due to tides. ... The List of reservoirs and dams is a link page for any reservoir or dam in the world. ... President Franklin D. Roosevelt signs the TVA Act The Tennessee Valley Authority is a New Deal agency created to generate electric power and control floods in a seven-U.S.-state region around the Tennessee River Valley. ... Micro hydro in North-West Vietnam Small hydro is the application of hydroelectric power on a commercial scale serving a small community or medium sized industry. ... Diagram of the TVA pumped storage facility at Racoon Mountain Pumped storage hydroelectricity is a method of storing and producing electricity to supply high peak demands by moving water between reservoirs at different elevations. ... Assembly of an Enercon E-70 wind turbine Modern technology uses large amounts of electrical power. ... William George Armstrong, 1st Baron Armstrong - Wikipedia, the free encyclopedia /**/ @import /skins-1. ...

External links

• Hydroelectric power
• World Commission on Dams report on environmental and social effects of large dams, including discussion of greenhouse gas emissions
• Hydroelectricity - Water potential powered systems, focusing on non-impactive small hydro. (FreeEnergyNews.com)
• River Energy - river turbine systems, not dam. (FreeEnergyNews.com)