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[[file:St54Figure46.JPG|thumb|400px|{{figure number|1}}World hydroelectric power generation and percent of the world's total electricity generation.<ref name+Salvador_2005>Salvador, Amos, Energy-A Historical Perspective and 21st Century Forecast: AAPG Studies in Geology 54, 208 p.</ref>]]

[[file:St54Figure46.JPG|thumb|400px|{{figure number|1}}World hydroelectric power generation and percent of the world's total electricity generation.<ref name+Salvador_2005>Salvador, Amos, Energy-A Historical Perspective and 21st Century Forecast: AAPG Studies in Geology 54, 208 p.</ref>]]

However, it was not until the flow of water was used in the generation of electricity that water started to make a major contribution to the world's supply of energy. Hydroelectric power is, as of 2005, the second largest source of electricity in the world (18%) after [[coal]], which supplies about 38%, but ahead of [[nuclear power]], [[natural gas]], and [[oil]], which contribute 17, 16, and 10%, respectively, of the total generated electricity.

However, it was not until the flow of water was used in the generation of electricity that water started to make a major contribution to the world's supply of energy. Hydroelectric power is, as of 2005, the second largest source of electricity in the world (18%) after [[coal]], which supplies about 38%, but ahead of [[nuclear power]], [[natural gas]], and [[oil as an energy source|oil]], which contribute 17, 16, and 10%, respectively, of the total generated electricity.

The world's first hydroelectric power plant was built at Godalming, in England, in 1881. Hydroelectric power developed rapidly during the 20th century, even in countries with other abundant sources of energy.

The world's first hydroelectric power plant was built at Godalming, in England, in 1881. Hydroelectric power developed rapidly during the 20th century, even in countries with other abundant sources of energy.

Nevertheless, hydroelectric power is still important in some countries, especially in those that are short of other sources of electricity but have large rivers originating in mountainous regions.  

Nevertheless, hydroelectric power is still important in some countries, especially in those that are short of other sources of electricity but have large rivers originating in mountainous regions.  

(For a discerning although somewhat supportive review of the pros and cons of hydropower, see the World Energy Council issue of the ''Survey of Energy Resources'' [http://www.worldenergy.org/publications/2001/world-energy-resources-2001/ 2001].)

World Energy Council Survey of Energy Resources, [http://www.worldenergy.org/publications/2001/world-energy-resources-2001/ 2001]. ''Discerning although somewhat supportive review of the pros and cons of hydropower.''

==See also==

==See also==