Hydro electric energy hydroelectric power, also called hydropower, electricity produced from generators driven by turbines that convert the potential energy of falling or fast-flowing water into mechanical energy. In the early 21st century, hydroelectric power was the most widely utilized form of renewable energy; in 2019 it accounted for more than 18 percent of the world’s total power generation capacity.
In the generation of hydroelectric power, water is collected or stored at a higher elevation and led downward through large pipes or tunnels (penstocks) to a lower elevation; the difference in these two elevations is known as the head. At the end of its passage down the pipes, the falling water causes turbines to rotate. The turbines in turn drive generators, which convert the turbines’ mechanical energy into electricity. Transformers are then used to convert the alternating voltage suitable for the generators to a higher voltage suitable for long-distance transmission. The structure that houses the turbines and generators, and into which the pipes or penstocks feed, is called the powerhouse.Hydroelectric power plants are usually located in dams that impound rivers, thereby raising the level of the water behind the dam and creating as high a head as is feasible. The potential power that can be derived from a volume of water is directly proportional to the working head, so that a high-head installation requires a smaller volume of water than a low-head installation to produce an equal amount of power. In some dams, the powerhouse is constructed on one flank of the dam, part of the dam being used as a spillway over which excess water is discharged in times of flood. Where the river flows in a narrow steep gorge, the powerhouse may be located within the dam itself. In most communities the demand for electric power varies considerably at different times of the day. To even the load on the generators, pumped-storage hydroelectric stations are occasionally built. During off-peak periods, some of the extra power available is supplied to the generator operating as a motor, driving the turbine to pump water into an elevated reservoir. Then, during periods of peak demand, the water is allowed to flow down again through the turbine to generate electrical energy. Pumped-storage systems are efficient and provide an economical way to meet peak loads.
tidal power
tidal power
In certain coastal areas, such as the Rance River estuary in Brittany, France, hydroelectric power plants have been constructed to take advantage of the rise and fall of tides. When the tide comes in, water is impounded in one or more reservoirs. At low tide, the water in these reservoirs is released to drive hydraulic turbines and their coupled electric generators (see tidal power)Falling water is one of the three principal sources of energy used to generate electric power, the other two being fossil fuels and nuclear fuels. Hydroelectric power has certain advantages over these other s
2. HISTORY OF HYDROPOWER
The first hydroelectric power dam in the world was built in
Appleton, Wisconsin in 1882.
In India, Jamshed ji Tata built the first hydroelectric power dam
in the Western Ghats of Maharashtra in the early 1900s to supply
power to Bombay’s Cotton and Textile Mills.
He took the British Government’s permission to build dams,
namely the Andhra, Sirowata, Valvan and Mulshi hydel dams in
the Western Ghats to generate electricity using high rainfalls in
the hills as storage.
3. Hydroelectric power
•India ranks 5th in terms of exploitable hydro-potential on
global scenario.
•In 2012, India is the 7th largest producer of hydroelectric
power with 114,000 GW hours
•With installed capacity of 37 GW , it produces 3.3% of the
world's total.
4. Hydropower is a renewable, non-polluting and environment
friendly source of energy.
Oldest energy technique known to mankind for conversion of
mechanical energy into electrical energy.
Contributes around 22% of the world electricity supply
generated.
The Working Group of the Planning Commission for the Twelfth
Plan has estimated a total requirement of 1403 Billion Units(BU)
per annum by the end of 12th Five Year Plan (2016–17) out of
which share of hydro generation is expected to be 12%. As per
Planning Commission, the capacity addition for the 12th Five Year
Plan on an all-India comprises 10,897 MW for Hydro.
5. •The public sector has a predominant share of 97% in this
sector,
•National Hydroelectric Power Corporation (NHPC),
•Northeast Electric Power Company (NEEPCO),
• Satluj Jal Vidyut Nigam (SJVNL),
• THDC,
• NTPC-Hydro
• are a few public sector companies engaged in
development of Hydroelectric Power in India.
6. •The hydro power plants at Darjeeling and Shimsha
(Shivanasamudra) were established in 1898 and 1902
respectively and are among the first in Asia.
•It is the most widely used form of renewable energy.
•The present installed capacity as on September 30, 2013 is
approximately 39,788.40 MW which is 17.39% of total
electricity generation in India.
7. •Bhakra Beas Management Board (BBMB), an illustrative state
owned enterprise in north India, has an installed capacity of 2.9
GW and generates 12,000-14,000 million units per year. The cost
of generation of energy after four decades of operation is about
20 paise/kWh.
•BBMB reservoirs annually supply water for irrigation to
12.5 million acres (51,000 km2; 19,500 sq mi) of agricultural land
of partner states, enabling northern India in its green revolution.
12. The movement of water can be used to make electricity.
Energy from
water is created by the force of water moving from a higher
elevation
to a lower elevation through a large pipe (penstock). When the
water
reaches the end of the pipe, it hits and spins a water wheel or
turbine.
The turbine rotates the connected shaft, which then turns the
generator, making electricity.
13.
14. its function is to convert the K.E of moving water into
mechanical energy
The water strikes and turns the large blades of a turbine, which
is attached to a generator above it by way of a shaft.
15. BASIC PRINCIPAL
Heart of the hydroelectric .
The basic process is to rotate a series of gaint magnets inside
coils of wire. This process moves electrons, which
produces electrical current.
17. Principle
• As the turbine turns, the excitor sends an electrical current
to the rotor. The rotor is a series of large electromagnets
that spins inside a tightly-wound coil of copper wire, called
the stator. The magnetic field between the coil and the
magnets creates an electric current.
18. POWER HOUSE AND EQUIPMENTS:-
In the scheme of hydropower the role of power house is to
protect the electromechanical equipment that convert the
potential energy of water into electricity.
Following are the equipments of power plant:
1.Valve 5.Condensor
2.Turbine 6.Protection System
3.Generator 7.DC emergency Supply
4.Control System 8.Power and current transformer
19. Efficiency
• A hydroelectric power plant operates under the
following conditions:
Water flow rate: 1.25 m3/s
River inlet: 1 atm., 4.7°C
Discharge: 1 atm., 5.1°C, 254 m below intake.
Assuming that water intlet and discharge ducts
have the same areas, and that no heat is
transferred to or absorbed from the
surroundings.
20. Efficiency
• density of water = 0.998 g/cm³ = 998 kg/m³
1.25m³ x 998 kg/m³ = 1248 kg
PE of the water is 1248 kg x 9.81 x 254 =
3.108e6 joules
E lost due to heating is
E = 4.17 kJ/(kg.K) x 1248 kg x 0.4K = 2082 kJ
Subtracting
E gained = 3108 kJ - 2082 kJ = 1026 kJ
eff = 1026/3108 = 33%
23. Station Operator State Generator
Units
Capacity
(MW)
Tehri Dam THDC Uttarakhand 4 x 250, 4 x 100,
4 x 250
2,400
Koyna MahaGenco Maharashtra 4 x 70, 4 x 80, 2 x
20, 4 x 80, 4 x
250
1.960
Srisailam Dam APGenco Andhra Pradesh 6 x 150, 7 x 110 1,670
Nathpa Jhakri SJVNL Himachal
Pradesh
6 x 250 1,500
Sharavathi KPCL Karnataka 10 x 103.5, 2 x
27.5, 4 x 60
1,469
Sardar Sarovar Sardar Sarovar
Narmada Nigam
Gujarat 6 x 200, 5 x 140 1,450
Bhakra Dam BBMB Punjab 5 x 108, 5 x 157 1,325
Kalinadi KPCL Karnataka 2 x 50, 1 x 135, 5
x 150, 3 x 50, 3 x
40
1,240
Chamera Dam NHPC Himachal
Pradesh
3 x 180, 3 x 100,
3 x 77
1,071
26. NAME COUNTRY INSTALLED CAPACITY
(MW)
Three Gorges Dam People's Republic of China 22,500
Itaipu Dam Brazil 14,000
Guri Venezuela 8,850
Tucuruí Brazil 8,370
Grand Coulee United States 6,809
Longtan Dam People's Republic of China 6,426
Krasnoyarsk Russia 6,000
Robert-Bourassa Canada 5,616
Churchill Falls Canada 5,428
29. In the last 30 years, the proportion of
hydroelectric capacity in the Indian power
system has considerably reduced.
Dropped from 46% in 1970 to 40% in 1980, 29%
in 1990 and 25% in 2008.
Reasons:-
Indian power supply industry has always
experienced the situation of shortages both in
energy and peaking requirements. To tide over
the shortage in shortest possible time, more
dependence was placed on sources of power
generation with shorter gestation period.
30. Future of hydroelectric power in India
The Working Group of the Planning Commission
for the Twelfth Plan has estimated a total
requirement of 1403 Billion Units(BU) per
annum by the end of 12th Five Year Plan
(2016–17), out of which share of hydro
generation is expected to be 12%. As per
Planning Commission, the capacity addition
for the 12th Five Year Plan on an all-India
comprises 10,897 MW for Hydro.
31. Acceptability in Society
Hydropower, while being projected as a clean and renewable
energy source, has time and again been resisted vociferously
in North East India in recent times because of the obvious and
unintended social and environmental impacts.
The anticipated negative impacts of the associated dam and
reservoir construction have cast a threat to the security of the
indigenous people in terms of water, food, livelihood, energy
and above all, the related socio-economic concerns.
This is all the more due to the uncertainties flowing from an
inadequate understanding of the possible geo-environmental
impacts in a highly sensitive terrain. To cope and live with the
potential negative ramifications of hydropower projects, a
comprehensive hydropower policy with emphasis on long-
term environmental and social security and sustainability is
imperative.
32. ADVANTAGES:
1) No fuel required
2) Cost of electricity is constant
3) No air-pollution is created
4) Long life
5) Cost of generation of electricity
6) Can easily work during high peak daily loads
7) Irrigation of farms
8) Water sports and gardens
9) Prevents floods
33. DISADVANTAGES:
1) Disrupts the aquatic ecosystems
2) Disruption in the surrounding areas
3) Requires large areas
4) Large scale human displacement
5) Very high capital cost or investment
6) High quality construction
7) Site specific
8) Effects on environment
9) Safety of the dams
34. CONCLUSIONS:
Hydroelectric power has always been an important part of the
world’s electricity supply, providing reliable, cost efficient,
electricity, and will continue to do so in the future.
Hydropower has environmental impacts, which are very different
from those of fossil fuel power plants. The actual effects of dams
and reservoirs on various ecosystems are only now becoming
understood.
The future demand of hydro electricity will depend on future
demand for electricity, as well as how societies value the
environmental impacts of hydro electric power compared to the
impacts of other sources of electricity.
