Represa Hidroeléctrica
Páginas: 12 (2900 palabras)
Publicado: 19 de noviembre de 2012
Hydroelectricity
Hydroelectricity is the term referring to electricity generated by hydropower; it is considered a renewable energy resource because it uses the Earth's water cycle to generate electricity. Water evaporates from the Earth's surface, forms clouds, precipitates back to earth, and flows toward the ocean.
History
Hydropower has been used since ancient times to grindflour and perform other tasks. In the mid-1770s, French engineer Bernard Forest de Bélidor published Architecture Hydraulique which described vertical- and horizontal-axis hydraulic machines.
The technology to take advantage of falling water and get useful mechanic energy is old. The history of hydropower started over 2000 years ago, when water wheels were being used by the ancient Greeks to grindgrain. It was not until the Middle Ages that the technology was spread to Europe.
Hydroelectric power was also important during the industrial revolution at the beginning of the 1800′s and provided mechanical power for textile and machine industries.
Probably the most important year in hydropower history was in 1831 when the first electric generator was invented by Michael Faraday. This laid thefoundation for us to learn how to generate electricity with hydropower almost half a century later, in 1878. [pic]
The first hydroelectric power plant, located in Appleton, Wisconsin, began to generate electricity already in 1882. The power output was at about 12.5 kW. 7 years later, in 1889, the total number of hydroelectric power plant solely in the US had reached 200. [pic]
In the19th century these power plants got an increased amount of commercial attention and was built rapidly in suitable areas all over the world. 1936 marks an important year – the largest hydroelectric power plant, the Hoover Dam, was opened and generated 1345 MW (installed capacity later increased 2080MW) from the flowing water in the Colorado River. Below is a picture of the Hoover Dam HydroelectricPower Plant.
[pic]
During the first half of the 1900’s hydropower became the world’s most important source of electricity.
In 2008, Three Gorges Dam in China was built. This is the largest power plant at current date, generating 22.500 MW, adding to China’s installed hydroelectric capacity of 196.79 GW (2009).
Hydropower is considered a mature technology contributes about 16% of globalelectricity generation today and will contribute even more in the future. There is almost 30 major hydroelectricity projects with at least 2.000 MW capacity under development, most of which are located in China.
[pic]
Hydroelectricity, how it works
The movement of water as it flows downstream creates kinetic energy that can be converted into electricity. A hydroelectric power plant convertsthis energy into electricity by forcing water, often held at a dam, through a hydraulic turbine that is connected to a generator. The water exits the turbine and is returned to a stream or riverbed below the dam.
Hydropower is mostly dependent upon precipitation and elevation changes; high precipitation levels and large elevation changes are necessary to generate significant quantities ofelectricity. Therefore, an area such as the mountainous Pacific Northwest has more productive hydropower plants than an area such as the Gulf Coast, which might have large amounts of precipitation but is comparatively flat.
[pic]
Actually, hydroelectric and coal-fired power plants produce electricity in a similar way. In both cases a power source is used to turn a propeller-like piece called aturbine, which then turns a metal shaft in an electric generator, which is the motor that produces electricity. A coal-fired power plant uses steam to turn the turbine blades; whereas a hydroelectric plant uses falling water to turn the turbine. The results are the same.
[pic]
Generating methods
Conventional (dams)
Most hydroelectric power comes from the potential energy of dammed...
Hydroelectricity is the term referring to electricity generated by hydropower; it is considered a renewable energy resource because it uses the Earth's water cycle to generate electricity. Water evaporates from the Earth's surface, forms clouds, precipitates back to earth, and flows toward the ocean.
History
Hydropower has been used since ancient times to grindflour and perform other tasks. In the mid-1770s, French engineer Bernard Forest de Bélidor published Architecture Hydraulique which described vertical- and horizontal-axis hydraulic machines.
The technology to take advantage of falling water and get useful mechanic energy is old. The history of hydropower started over 2000 years ago, when water wheels were being used by the ancient Greeks to grindgrain. It was not until the Middle Ages that the technology was spread to Europe.
Hydroelectric power was also important during the industrial revolution at the beginning of the 1800′s and provided mechanical power for textile and machine industries.
Probably the most important year in hydropower history was in 1831 when the first electric generator was invented by Michael Faraday. This laid thefoundation for us to learn how to generate electricity with hydropower almost half a century later, in 1878. [pic]
The first hydroelectric power plant, located in Appleton, Wisconsin, began to generate electricity already in 1882. The power output was at about 12.5 kW. 7 years later, in 1889, the total number of hydroelectric power plant solely in the US had reached 200. [pic]
In the19th century these power plants got an increased amount of commercial attention and was built rapidly in suitable areas all over the world. 1936 marks an important year – the largest hydroelectric power plant, the Hoover Dam, was opened and generated 1345 MW (installed capacity later increased 2080MW) from the flowing water in the Colorado River. Below is a picture of the Hoover Dam HydroelectricPower Plant.
[pic]
During the first half of the 1900’s hydropower became the world’s most important source of electricity.
In 2008, Three Gorges Dam in China was built. This is the largest power plant at current date, generating 22.500 MW, adding to China’s installed hydroelectric capacity of 196.79 GW (2009).
Hydropower is considered a mature technology contributes about 16% of globalelectricity generation today and will contribute even more in the future. There is almost 30 major hydroelectricity projects with at least 2.000 MW capacity under development, most of which are located in China.
[pic]
Hydroelectricity, how it works
The movement of water as it flows downstream creates kinetic energy that can be converted into electricity. A hydroelectric power plant convertsthis energy into electricity by forcing water, often held at a dam, through a hydraulic turbine that is connected to a generator. The water exits the turbine and is returned to a stream or riverbed below the dam.
Hydropower is mostly dependent upon precipitation and elevation changes; high precipitation levels and large elevation changes are necessary to generate significant quantities ofelectricity. Therefore, an area such as the mountainous Pacific Northwest has more productive hydropower plants than an area such as the Gulf Coast, which might have large amounts of precipitation but is comparatively flat.
[pic]
Actually, hydroelectric and coal-fired power plants produce electricity in a similar way. In both cases a power source is used to turn a propeller-like piece called aturbine, which then turns a metal shaft in an electric generator, which is the motor that produces electricity. A coal-fired power plant uses steam to turn the turbine blades; whereas a hydroelectric plant uses falling water to turn the turbine. The results are the same.
[pic]
Generating methods
Conventional (dams)
Most hydroelectric power comes from the potential energy of dammed...
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