Hydroelectricity is the
term referring to electricity generated by hydropower; the
production of electrical power through the use of the gravitational force of
falling or flowing water. It is the most widely used form of renewable
energy. Hydropower is produced in 150 countries, with the
Asia-Pacific region generating 32 percent of global hydropower in 2010. China
is the largest hydroelectricity producer, with 721 terawatt-hours of production
in 2010, representing around 17 percent of domestic electricity use. There are now
three hydroelectricity plants larger than 10 GW: the Three
Gorges Dam in China, Itaipu
Dam across the Brazil/Paraguay
border, and Guri Dam in Venezuela.
Ten of the largest
hydroelectric producers as at 2009.
|
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Country
|
Annual hydroelectric
production (TWh) |
Installed
capacity (GW) |
Capacity
factor |
% of total
capacity |
China
|
652.05
|
196.79
|
0.37
|
22.25
|
Canada
|
369.5
|
88.974
|
0.59
|
61.12
|
Brazil
|
363.8
|
69.080
|
0.56
|
85.56
|
United
States
|
250.6
|
79.511
|
0.42
|
5.74
|
Russia
|
167.0
|
45.000
|
0.42
|
17.64
|
Norway
|
140.5
|
27.528
|
0.49
|
98.25
|
India
|
115.6
|
33.600
|
0.43
|
15.80
|
Venezuela
|
85.96
|
14.622
|
0.67
|
69.20
|
Japan
|
69.2
|
27.229
|
0.37
|
7.21
|
Sweden
|
65.5
|
16.209
|
0.46
|
44.34
|
Hydroelectric power
for the Nation
- China is the largest hydroelectricity power producer and Canada is the largest producer of hydroelectricity in the world
- Turkey is producing least units of electricity with hydroelectricity power plant.
Hydroelectricity in india
With
more than 70% of the electricity requirement in India being contributed from
thermal sources And various issues and problems such as peaking shortage, low
PLF operation of many thermal generating stations etc., there is an urgent need
to review the prevailing energy mix. Hydropower potential is abundantly
available to the tune of about 148,700 MW and more
Than 75% of which remaining
untapped and with all the inherent advantages associated with
hydropower, the energy mix can be
improved by the development of the balance huge potential As per the Central
Electricity Authority (CEA) estimates, India would require an addition of at least
161 Giga Watt of generation capacity by the year 2016-17 over the
existing generation capacity. Out of total hydro potential of 84,044 MW at 60%
load factor from 845 schemes with a total installed capacity of nearly 148,700
MW, less than 25% hydro potential has been exploited so far and balance 75%
hydro potential remains untapped. It thus comes out that bulk of the future
requirement of the electric power can be met by the hydropower development
HYDROPOWER
DEVELOPMENT POTENTIAL
India is blessed with huge amount
of hydropower potential major amount of which still remain untapped. In terms
of hydropower potential, India ranks fifth in terms of exploitable hydro potential
on global scenario.
Hydropower potential of the
country has been assessed by Central Electricity Authority (CEA) in1987 as
84044 MW from 845 schemes with a total installed capacity of about 148,700 MW. Besides
56 sites for pumped storage scheme with a total installed capacity of about
93,920 MW have also been identified in various regions of the country. In
addition to potential of medium and major hydro schemes 1512 small
hydroelectric schemes having aggregate installed capacity of 6782 MW on canal
falls/rivers have also been identified.
Hydro potential developed so far
is only about 23 percent of the total assessed potential and
another about 6.5 percent is in
various stages of development, thus about 70 percent of the hydro potential
still remains to be developed. Share of hydropower which was about 37 percent
at the time of independence in the year 1947 continued to rise till 1963 when achieved
a figure of about 50 percent. Thereafter, the share of hydropower has been
continuously declining and at present it is only about 23 percent of the total
installed capacity of the country. The ideal hydrothermal ratio for Indian
power system has been assessed as 40:60 for reliability of system operation.
The present ratio is about 23:67 which needs to be augmented to meet peak load requirements
as well as to improve system reliability. Out of 845 schemes identified by CEA
(Central Electricity Authority) in reassessment studies, at
present , 288 hydro schemes with
an aggregate installed capacity of about 42000 MW are either under
operation/implementation. The balance schemes include about 164 schemes each of
which having installed capacity of 25 MW or less of total capacity of 2300 MW.
Thus about 400schemes having total likely installed capacity of above 1,00,000
MW are yet to be taken up for development. Similarly share of Hydro Power in
installed capacity which rose to 50.62% in the year 1963, experienced a steep
fall, and at present it is only just over 23% of the total capacity which is required
to be enhanced to at least 40% (though there is no upper limit) so as to
achieve hydro/thermal mix of 40: 60 leading to better system availability and
reliability.
HYDROPOWER
AND ENVIRONMENT
Hydropower is nonpolluting, but does have environmental impacts
Hydropower does not pollute the water or the air. However, hydropower facilities can have large environmental impacts by changing the environment and affecting land use, homes, and natural habitats in the dam area.
Most hydroelectric power plants have a dam and a reservoir. These structures may obstruct fish migration and affect their populations. Operating a hydroelectric power plant may also change the water temperature and the river's flow. These changes may harm native plants and animals in the river and on land. Reservoirs may cover people's homes, important natural areas, agricultural land, and archeological sites. So building dams can require relocating people. Methane, a strong greenhouse gas, may also form in some reservoirs and be emitted to the atmosphere.
Region
wise contribution of Hydropower
REGION
|
PERCENTAGE
|
NORTH
|
30.34
|
WEST
|
13.86
|
SOUTH
|
37.2
|
EAST
|
15.27
|
NORTH-EAST
|
37.72
|
INDIA
|
24.74
|
