hydro power plant report

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A
SEMINAR REPORT
On
HYDRO POWER PLANT
Submitted
By
MD ASIF
Department of Mechanical Engineering
GLOBAL TECHNICAL CAMPUS
GLOBAL COLLEGE OF TECHNOLOGY
ITS-1, IT Park, EPIP SITAPURA JAIPUR
DEPARTMENT OF MECHANICAL ENGG
Global College of Technology,
Sitapura, Jaipur 302022
2013-17

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Global College of Technology
DEPARTMENT OF MECHANICAL ENGINEERING
JAIPUR (RAJASTHAN)-302022
CERTIFICATE
GLOBAL COLLEGE OF TECHNOLOGY
Department of Mechanical Engineering
This is to certify that this seminar report on “Hydro power plant” by MD ASIF
13EGCME724. To the department of Mechanical engineering, GCT Jaipur, for
award of degree of Btech in Mechanical Engineering is bonafide record of work
done by him. The content of the seminar record has not been to any college or
university for the award of degree.
Mr. SUNIL KUMAR JATOLIYA
MAHESH KUMAR YADAV MD ASIF
CO-ORDINATOR Student
(Signature) (Signature)

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ACKNOWLEDGEMENT
I would like to thank Mr Sunil Kumar Jatoliya (Assistant professor) and Mahesh Kumar yadav
(Assistant professor) department of Mechanical engineering. It would’nt be possible complete the
work without his assistance and hardwork, I’m obliged to his great effort on presenting us firmly
in seminar.
I would like to thank Mrs Bhavna Mathur, HOD, department of mechanical engineering, she has
always created good environment to enhance confidence and boost the student to present
themselves. She is good support through every thick and thin.
I’m also thankful to the hardworking effort of Prof.mrs Renu Joshi(Director) Git. She is the back
bone of our each and every move.
MD ASIF
(13EGCME724)
Mechanical Engineering

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CONTENTS
TITLE PAGE NO.
CERTIFICATE (II)
ACKNOWLEDGEMENT (III)
CONTENT (IV)
LIST OF FIGURE (VI)
1 ABSTRACT 1
2 INTRODUCTION 2
3 TERMS RELATED TO HYDRO POWER PLANT 6
3 ELEMENTS/COMPONENT OF HYDRO POWER PLANT 8
3.1 Water reservoir 8
3.2 Dam 9
3.3 Spillway 10
3.4 Intake 11
3.5 Fore bay 11
3.6 Penstock 11
3.7 Pressure tunnel 11
3.8 Surge tank 11
3.9 Turbine 12

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3.10 Power house 15
3.11 Draft tube 17
3.12 Tail race 18
3.13 Switch yard for transmission of power 18
1. CLASSIFICATION OF HYDRO POWER PLANT 19
4.1 According to quantity of water 19
4.2 According to availability of head of water 21
4.3 According to load characteristics 23
4.4 According to plant capacity 24
4.5 According to type of fall 24
2. SITE SELECTION FOR HYDRO POWER PLANT 25
3. WORKING 27
4. ADVANTAGES AND DISADVANTAGES OF HYDRO POWER PLANT 29
5. CONCLUSION 32
6. REFRENCES 33

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LIST OF FIGURES
FIG. NO. TITLE PAGE NO.
Fig. 3.1 Elements of hydro power plant 8
Fig. 3.2 Surge tank 12
Fig. 3.3 Types of turbines 13
Fig. 3.4 Pelton wheel tubine 14
Fig. 3.5 Keplan turbine 14
Fig. 3.6 Generator 16
Fig. 3.7 Types of draft tube 18
Fig. 4.1 Tidal plant 21
Fig. 4.2 Low head power plant 24
Fig. 4.3 Medium head power plant 22
Fig. 4.4 High head power plant 23
Fig. 6.1 Working of hydro power plant 28

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ABSTRACT
In hydro power plant we use gravitational force of fluid water to run the turbine which is
coupled with electric generator to produce electricity. This power plant plays an important role
to protect our fossil fuel which is limited, because the generated electricity in hydro power
station is the use of water which is renewable source of energy and available in lots of amount
without any cost. The big advantage of hydro power is the water which the main stuff to
produce electricity in hydro power plant is free, it not contain any type of pollution and after
generated electricity the price of electricity is average not too much high.
Hydropower is the cheapest way to generate electricity today. That's because once a dam has
been built and the equipment installed, the energy source—flowing water—is free. It's a clean
fuel source that is renewable yearly by snow and rainfall.

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(v)
Chapter-1
INTRODUCTION
Hydropower is electricity generated using the energy of moving water. Rain or melted snow,
usually originating in hills and mountains, create streams and rivers that eventually run to the
ocean. The energy of that moving water can be substantial, as anyone who has been whitewater
rafting knows.This energy has been exploited for centuries. Farmers since the ancient Greeks have
used water wheels to grind wheat into flour. Placed in a river, a water wheel picks up flowing
water in buckets located around the wheel. The kinetic energy of the flowing river turns the wheel
and is converted into mechanical energy that runs the mill.
In the late 19th century, hydropower became a source for generating electricity. The first
hydroelectric power plant was built at Niagara Falls in 1879. In 1881, street lamps in the city of
Niagara Falls were powered by hydropower. In 1882 the world’s first hydroelectric power plant
began operating in the United States in Appleton, Wisconsin.
A typical hydro plant is a system with three parts: an electric plant where the electricity is
produced; a dam that can be opened or closed to control water flow; and a reservoir where water

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can be stored. The water behind the dam flows through an intake and pushes against blades in a
turbine, causing them to turn. The turbine spins a generator to produce electricity. The amount of
electricity that can be generated depends on how far the water drops and how much water moves
through the system. The electricity can be transported over long-distance electric lines to homes,
factories, and businesses.
Hydroelectric power provides almost one-fifth of the world's electricity. China, Canada, Brazil,
the United States, and Russia were the five largest producers of hydropower in 2004. One of the
world's largest hydro plants is at Three Gorges on China's Yangtze River. The reservoir for this
facility started filling in 2003, but the plant is not expected to be fully operational until 2009. The
dam is 1.4 miles (2.3 kilometers) wide and 607 feet (185 meters) high.The biggest hydro plant in
the United States is located at the Grand Coulee Dam on the Columbia River in northern
Washington. More than 70 percent of the electricity made in Washington State is produced by
hydroelectric facilities.
Hydropower is also readily available; engineers can control the flow of water through the turbines
to produce electricity on demand. In addition, reservoirs may offer recreational opportunities, such
as swimming and boating. But damming rivers may destroy or disrupt wildlife and other natural
resources. Some fish, like salmon, may be prevented from swimming upstream to spawn.
Technologies like fish ladders help salmon go up over dams and enter upstream spawning areas,
but the presence of hydroelectric dams changes their migration patterns and hurts fish populations.
Hydropower plants can also cause low dissolved oxygen levels in the water, which is harmful to
river habitats.
Power system mainly contains three parts namely generation, transmission and distribution.
Generation means how to generate electricity from the available source and there are various
methods to generate electricity but in this article we only focused on generation of electricity by
the means of hydro or water (hydro power plant). As we know that the power plant is defined as
the place where power is generated from a given source, so here the source is hydro that’s why we
called it hydro power plant.
 Hydropower is a renewable, non-polluting and environment friendly source of energy.

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 Oldest energy technique known to mankind for conversion of mechanical energy into
electrical energy.
 Contributes around 22% of the world electricity supply generated.
 Maximum benefits in minimum time.
 Offers the most fastest economical means to enhance power supply, improve living
standards, stimulate industrial growth and enhance agriculture with the least environmental
impact and without heavy transmission losses .
 Due to less transmission losses there is a reduction in distribution cost as well.
HISTORY OF HYDRO POWER
The world’s first hydroelectric project was used to power a single lamp in the Cragside country
house in Northumberland, England, in 1878. Four years later, the first plant to serve a system of
private and commercial customers was opened in Wisconsin, USA, and within a decade, hundreds
of hydropower plants were in operation.In North America, hydropower plants were installed at
Grand Rapids, Michigan (1880), Ottawa, Ontario (1881), Dolgeville, New York (1881), and
Niagara Falls, New York (1881). They were used to supply mills and light some local buildings.
By the turn of the 20th
century the technology was spreading round the globe, with Germany
producing the first three-phase hydro-electric system in 1891, and Australia launching the first
publicly owned plant in the Southern Hemisphere in 1895.In 1895, the world’s largest
hydroelectric development of the time, the Edward Dean Adams Power Plant, was created at
Niagara Falls.
In 1905, a hydroelectric station was built on the Xindian creek near Taipei, with an installed
capacity of 500 kW. This was quickly followed by the first station in mainland China, the
Shilongba plan in the Yunnan province, which was built in 1910 and put into operation in 1912.
Upon completion Shilongba had an installed capacity of 480 kW – today it is still in operation with
an installed capacity of 6 MW. In the first half of the 20th
century, the USA and Canada led the
way in hydropower engineering. At 1,345 MW, the Hoover Dam on the Colorado River became
the world’s largest hydro-electric plant in 1936, surpassed by the Grand Coulee Dam (1,974 MW
at the time, 6,809 MW today) in Washington in 1942.

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From the 1960s through to the 1980s, large hydropower developments were carried out in Canada,
the USSR, and Latin America.
Over the last few decades, Brazil and China have become world leaders in hydropower. The Itaipu
Dam, straddling Brazil and Paraguay, opened in 1984 at 12,600 MW (it has since been enlarged
and uprated to 14,000 MW), and is today only eclipsed in size by the 22,500 MW China Three
Gorges Dam, which opened in 2008.
Hydropower today
Into the 21st
century, hydropower continues to catalyse growth around the world. For example, it
has played a key role in transforming Brazil into the seventh largest country by GDP in 2012; not
least through a period of very rapid economic growth between 2000 and 2010, which saw its
increase in (nominal GDP) value only outpaced by the USA and China. This was only possible
with the massive increases in electricity output that have been delivered by its investment in
hydropower. In 2010, Brazil produced 349,000 GWh of electricity, and by 2011 this had increased
by 40 per cent to 489,000 GWh. Remarkably, just 2 per cent of this energy came from imports,
and around 80 per cent from hydropower.
The result is a very modern fleet of very large hydropower stations – of which at least 24 are rated
at 500 MW or above. Brazil has made the most of its rich hydrological resource to transform itself
into a leader on the world stage, keep costs down and maintain its energy independence from the
rest of the world.This is just one example of the massive stimulus to economic growth that
hydropower can provide; as we look towards the future the technology has a huge role to play in
bringing growth and prosperity to the developing world.

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Chapter-2
TERMS RELATED TO HYDRO POWER PLANT
FRL (FULL RESERVOIR LEVEL)
FRL is the Upper level of the reservoir (selected based on techno-economic& submergence
considerations)
MDDL (MINIMUM DRAWDOWN LEVEL)
Lowest level up to which the reservoir level could be drawn down to withdraw waters for energy
generation (selected from considerations of silt & turbine operational limits) is called as minimum
drawdown level.
GROSS STORAGE
Total storage capacity of the reservoir is termed as gross storage.
DEAD STORAGE
Reservoir storage which cannot be used for generation and is left for silt deposition( below MDDL)
is called as dead reservoir.
LIVE STORAGE
It is the storage in the reservoir which is available for power generation.(between FRL & MDDL)

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FIRM POWER
Firm power is continuous power output in the entire period of hydrological data at 90%
dependability.
FIRM ENERGY
Energy generated corresponding to firm power is called as firm energy.
PEAK ENERGY
Peak energy is electric energy supplied during periods of relatively high system demands.
OFF-PEAK ENERGY
Off peak energy is electric energy supplied during periods of relatively low system demands.
LOAD FACTOR
Load factor is the ratio of the average load over a designated period to the peak-load occurring in
that period.
DIURNAL STORAGE
Storage required to meet daily variations in load demand is termed as diurnal storage . It depends
upon the minimum flows and peak discharges.
CRITICAL PERIOD
Most critical period with respect to system load requirements, begins when reservoir begins
delivering water for generation from full i.e the available storage is fully drafted at one point during
the period; and the critical period ends when the storage has completely refilled.
CRITICAL DRAW DOWN PERIOD
That portion of the critical period in which reservoir live storage is completely drafted while
meeting firm energy requirements is called as critical draw down period.
DESIGN HEAD
The head at which the turbine will operate to give the best overall efficiency under various
operating conditions is called as design head.
GROSS HEAD

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It is the difference of elevations between water surfaces of the forebay/ dam and tailrace under
specified conditions.
NET HEAD
The gross head chargeable to the turbine less all hydraulic losses in water conductor system is
termed as net head.
WATER-HAMMER EFFECT
The water hammer is defined as the change in pressure rapidly above or below normal pressure
caused by sudden change in the rate of water flow through the pipe, according to the demand of
prime mover i.e. turbine
Chapter-3
ELEMENTS/COMPONENT OF HYDRO POWER PLANT

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FIGURE 3.1: Elements of hydro power plant
3.1 WATER RESERVOIR
An open-air storage area usually formed by masonry or earthwork where water is collected and
kept in quantity so that it may be drawn off for use.
Changes in weather cause the natural flow of streams and rivers to vary greatly with time. Periods
of excess flows and valley flooding may alternate with low flows or droughts. The role of water-
storage reservoirs, therefore, is to impound water during periods of higher flows, thus preventing
flood disasters, and then permit gradual release of water during periods of lower flows. Simple
storage reservoirs were probably created early in human history to provide water for drinking and
for irrigation. From southern Asia and northern Africa the use of reservoirs spread to Europe and
the other continents.
Reservoirs ordinarily are formed by the construction of dams across rivers, but off-channel
reservoirs may be provided by diversion structures and canals or pipelines that convey water from
a river to natural or artificial depressions.
When streamflow is impounded in a reservoir, the flow velocity decreases and sediment is
deposited. Thus, streams that transport much suspended sediment are poor sites for reservoirs;
siltation will rapidly reduce storage capacity and severely shorten the useful life of a small
reservoir. Even in larger reservoirs, sedimentation constitutes a common and serious problem.
Because removal of the deposited sediments from reservoirs is generally too costly to be practical,
reservoirs on a sediment-laden stream are characteristically planned to provide a reserve of storage
capacity to offset the depletion caused by sedimentation. Despite this, the life expectancy of most
reservoirs does not exceed 100 years at present sedimentation rates.
 The water reservoir is the place behind the dam where water is stored.
 The water in the reservoir is located higher than the rest of the dam structure.
 The height of water in the reservoir decides how much potential energy the water
 The higher the height of water, the more its potential energy.
 The high position of water in the reservoir also enables it to move downwards effortlessly.

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 The height of water in the reservoir is higher than the natural height of water flowing in
the river, so it is considered to have an altered equilibrium.
 This also helps to increase the overall potential energy of water, which helps ultimately
produce more electricity in the power generation unit.
3.2 DAM
A structure built across a stream, river, or estuary to retain water. Dams are built to provide water
for human consumption, for irrigating arid and semiarid lands, or for use in industrial processes.
They are used to increase the amount of water available for generating hydroelectric power, to
reduce peak discharge of floodwater created by large storms or heavy snowmelt, and to increase
the depth of water in a river in order to improve navigation and allow barges and ships to travel
more easily. Dams can also provide a lake for recreational activities such as swimming, boating,
and fishing. Many dams are built for more than one purpose; for example, water in a single
reservoir can be used for fishing, to generate hydroelectric power, and to support an irrigation
system. Water-control structures of this type are often designated multipurpose dams.
Auxiliary works that can help a dam function properly include spillways, movable gates, and
valves that control the release of surplus water downstream from the dam. Dams can also include
intake structures that deliver water to a power station or to canals, tunnels, or pipelines designed
to convey the water stored by the dam to far-distant places. Other auxiliary works are systems for
evacuating or flushing out silt that accumulates in the reservoir, locks for permitting the passage
of ships through or around the dam site, and fish ladders (graduated steps) and other devices to
assist fish seeking to swim past or around a dam.
A dam can be a central structure in a multipurpose scheme designed to conserve water resources
on a regional basis. Multipurpose dams can hold special importance in developing countries, where
a single dam may bring significant benefits related to hydroelectric power production, agricultural
development, and industrial growth. However, dams have become a focus of environmental
concern because of their impact on migrating fish and riparian ecosystems. In addition, large
reservoirs can inundate vast tracts of land that are home to many people, and this has fostered
opposition to dam projects by groups who question whether the benefits of proposed projects are
worth the costs.

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 The dam is the most important component of hydroelectric power plant.
 The dam is built on a large river that has abundant quantity of water throughout the year.
 It should be built at a location where the height of the river is sufficient to get the maximum
possible potential energy from water.
3.3 SPILLWAY
Excess accumulation of water endangers the stability of dam construction. Also in order to avoid
the over flow of water out of the dam especially during rainy seasons spillways are provided. This
prevents the rise of water level in the dam. Spillways are passages which allows the excess water
to flow to a storage area away from the dam
3.4 INTAKE
These are the gates built on the inside of the dam. The water from reservoir is released and
controlled through these gates. These are called inlet gates because water enters the power
generation unit through these gates. When the control gates are opened the water flows due to
gravity through the penstock and towards the turbines.
3.5 FOREBAY
A forebay (or head pond) is an enlarged body of water provided at the downstream end of canal
just at the upstream of penstocks to act as a small balancing reservoir. A forebay is required in the
case of run-of-river plants at the upstream of the diversion work. In case of a storage plant, it is
required only when the power house is located away from the dam and the water is conveyed to
the power house through a power canal. If the power house is located at the toe of the dam, a
separate forebay is not required since the penstocks directly take water from the reservoir which
itself act as a forebay.
The main function of forebay is to store some water to act as a regulating reservoir for the
penstocks.
3.6 PENSTOCK

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The penstock is the long pipe or the shaft that carries the water flowing from the reservoir towards
the power generation unit, comprised of the turbines and generator. The water in the penstock
possesses kinetic energy due to its motion and potential energy due to its height.The total amount
of power generated in the hydroelectric power plant depends on the height of the water reservoir
and the amount of water flowing through the penstock.The amount of water flowing through the
penstock is controlled by the control gates.
3.7 PRESSURE TUNNEL
It is a passage that carries water from the reservoir to the surge tank
3.8 SURGE TANK
It is a safety device.Whenever the electrical load on the generator drops down suddenly, the
governor partially closes the gates which admits water flow to the turbine. Due to this sudden
decrease in the rate of water flow to the turbine, there will be sudden increase of pressure in the
penstock. This phenomenon results in hammering action called water hammer in the penstock.
When turbine gates are suddenly opened to produce more power, there is a sudden rush of water
through penstock and it might cause a vacuum in water flow system which might collapse
penstock. Penstock withstands positive hammer and vacuum effects.
Surge tank acts as a temporary reservoir. It helps in stabilizing the velocity and pressure in
penstock and thereby saves penstock from getting damaged.To serve as supply tank to the turbine
in case of increased load conditions, and storage tank in case of low load conditions.

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FIGURE 3.2: Surge tank
3.9 TURBINE
Water flowing from the penstock is allowed to enter the power generation unit, which houses the
turbine and the generator. When water falls on the blades of the turbine the kinetic and potential
energy of water is converted into the rotational motion of the blades of the turbine. The rotating
blades causes the shaft of the turbine to also rotate. The turbine shaft is enclosed inside the
generator. The hydro project are site specific as such the use of standard or off the shelf unit may
not be possible.
The selection of type of turbine is made on the basis of “Head”. The broad classification is
given below.
 Low head(upto60 m) —Kaplan Turbine

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 Medium head(30to600m)—Francis Turbine
 High head (more than300m) —Pelton
FIGURE 3.3: Types of turbines
I. IMPULSE TURBINES
Impulse turbines change the velocity of a water jet. The jet pushes on the turbine's curved blades
which changes the direction of the flow. The resulting change in momentum causes a force on the

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FIGURE 3.4: Pelton wheel tubine
FIGURE 3.5: Keplan turbine
turbine blades. Since the turbine is spinning, the force acts through a distance and the diverted water
flow is left with diminished energy. Prior to hitting the turbine blades, the water's pressure is
converted to kinetic energy by a nozzle and focused on the turbine. No pressure change occurs at
the turbine blades, and the turbine doesn't require a housing for operation. Impulse turbines are most

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often used in very high head applications. Newton's second law describes the transfer of energy for
impulse turbines.
II. REACTION TURBINE
Reaction turbines are acted on by water, which changes pressure as it moves through the turbine and
gives up its energy. They must be encased to contain the water pressure (or suction), or they must
be fully submerged in the water flow. Newton's third law describes the transfer of energy for reaction
turbines. Most water turbines in use are reaction turbines and are used in low and medium head
applications. In reaction turbine pressure drop occurs in both fixed and moving blades.
3.10 POWER HOUSE
a) A power house usually contains following components:
b) Hydraulic turbines
c) Electric generators
d) Governors
e) Gate valves
f) Relief valves
g) Water circulation pumps
h) Air ducts
i) Switch board and instruments
j) Storage batteries
k) Cranes
GENERATOR
Hydro generator is coupled to the turbine and converts the mechanical energy transmitted
by the turbine to electrical energy. Generators may be of:
a) Suspended type
b) Umbrella type
Main Generator components include:
 Stator
 Rotor

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 Upper Bracket
 Lower Bracket
 Thrust Bearing & Guide Bearings
 Slip Ring & Brush Assembly
 Air Coolers
 Brakes & Jacks
 Stator Heaters
GOVERNOR
The hydraulic turbine governor is equipment for controlling the guide vanes by detecting
turbine speed and its guide vane opening in order to keep the turbine speed stable or to regulate
it's outputGovernors are provided with the following features;
 Quick Response and Stable Control
 Guide Vane Opening Detection with High Accuracy
 Speed Detection with High Accuracy
 High Reliability
 Easy Maintenance
FIGURE 3.6: Generator

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3.11 DRAFT TUBE
Draft tube is located between lower ring of turbine and tail race. It conveys water after discharge
from runner to tail race tunnel.Draft tube (DT) gates are provided for isolating the Power house
and tail pool before taking maintenance of the turbine.The DT gates are provided with hoisting
mechanism. The DT gate may be a single piece or a combination of more than one pieceIt allows
the turbine to be set above tail water level, without loss of head, to facilitate inspection and
maintenanceIt regains, by diffuser action, the major portion of the kinetic energy delivered to it
from the runner.
Reaction turbines must be completely enclosed because a pressure difference exists between the
working fluid (water) in the turbine and atmosphere. Therefore, it is necessary to connect the
turbine outlet by means of a pipe known as draft tube upto tailrace level.
Types of Draft Tubes
i. Conical Draft Tube.
This is known as tapered draft tube and used in all reaction turbines where conditions permit. It is
preferred for low specific speed and vertical shaft Francis turbine. The maximum cone angle of
this draft tube is limited to 8° (a = 4°). The hydraulic efficiency of such type of draft tube is 90%.
ii. Elbow Type Draft Tube.
The elbow type draft tube is often preferred in most of the power plants, where the setting of
vertical draft tube does not permit enough room without excessive cost of excavation.
iii. Moody Draft Tube.
This draft tube has an advantage that its conical portion at the center reduces the whirl action of
water moving with high velocity centre reduces.

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FIGURE 3.7: Types of draft tube
3.12 TAIL RACE
Tail race is a passage for discharging the water leaving the turbines, into the river.
3.13 SWICH YARD FOR TRANSMISSION OF POWER
The electrical equipment of a hydro-electric power station includes like transformer, circuit
breaker & other switching & protective devices.

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Chapter-4
CLASSIFICATION OF HYDRO POWER PLANT
The classification of hydro electric power plant depend on the following factors:
According to quantity of water
i. Run of river plant
ii. Storage plant.
iii. Pumped storage plants.
iv. Tidal plants
According to availability of head of water
i. Low head plant
ii. Medium head plant
iii. High head plants
According to load characteristics
i. Base load plants
ii. Peak load plants
According to plant capacity
i. Micro hydel plants
ii. Medium capacity plants
iii. High capacity plants
iv. Super hydro plants
According to type of fall
i. Concentrated fall plants
ii. Divided fall plants
4.1 ACCORDING TO QUANTITY OF WATER
It is following types.
i.Run of river plant.
As the name implies, the project is planned as run of the river.Water is diverted from the river,
routed through the water conductor system and finally water after generation of power is thrown

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back to the river at a lower level on down stream.It takes advantage of the drop in elevation that
occurs over a distance in the river and does not involve water storage. Power generation fluctuates
with the river flow and the firm power is considerably low, as it depends on the minimum mean
discharge.Canal power projects are also run-of-river projects.
ii.Storage plant.
Storage projects provide storage or pondage and thereby, evens out stream flow fluctuations and
enhances the water head.It increases firm power and total power generation by regulating the flow.
Providing storage is complicated and costly as it involves construction of dam.
iii.Pumped storage plants.
Pump storage projects involve reversible turbines, which can generate power from water of upper
reservoir during peak hours and pump back water from lower reservoir to the upper reservoir
during off peak hours.These projects are advantageous in power system of mix type, which have
thermal and nuclear power houses in addition to hydro power projects.Pump storage project
utilizes the off peak surplus power of the grid in lifting the water from lower reservoir to higher
reservoir and generates power during peak hours thus flattening the load curve.
iv.Tidal plants.
A tidal power plant makes use of the daily rise and fall of ocean water due to tides; such sources are
highly predictable, and if conditions permit construction of reservoirs, can also be dispatchble to
generate power during high demand periods. Less common types of hydro schemes use
water's kinetic energy or undammed sources such as undershot waterwheels.Tidal power is extracted
from the Earth's oceanic tides; tidal forces are periodic variations in gravitational attraction exerted
by celestial bodies. These forces create corresponding motions or currents in the world's oceans. The
magnitude and character of this motion reflects the changing positions of the Moon and Sun relative
to the Earth, the effects of Earth's rotation, and local geography of the sea floor and coastlines.

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FIGURE 4.1: Tidal plant
4.2 ACCORDING TO AVAILABILITY OF HEAD OF WATER
i. Low head plant
They consist of dam across the river.A sideway stream diverges from the river at the dam,
powerhouse is constructed over the stream, which further joins the river.Vertical shaft Francis or
Kaplan turbine are used commonly.
ii. Medium head plant.
It is used normally when Head : 30 to 100m
 Uses Francis Turbine
 Forebay provided at the beginning of penstock at as reservoir.
 Water is carried in open canals from main reservoir to forebay then to
powerhouse through penstock.

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FIGURE 4.2: Low head power plant
FIGURE 4.3: Medium head power plant

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iii. High head plants:
 Head: 100m to 2000m
 Water is stored in the lake over the mountain during high rainy season or when
snow melts.
 Water should be available throughout the year.
 Pelton Wheel turbine is used.
FIGURE 4.4: High head power plant
4.3 ACCORDING TO LOAD CHARACTERISTICS
i. Base load plants
They cater to the base load of the system, they need to supply constant power when connected to
the grid.
ii. Peak load plants
Some of the plants supply average load but also some peak load. Other peak load plants are
required to work only during peak load hours.

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4.4 ACCORDING TO PLANT CAPACITY
i. Micro hydel plants
A micro hydel plant has the capacity less than 5 MW.
ii. Medium capacity plants
A medium capacity plant has the capacity between 5MW and 100 MW.
iii. High capacity plants
A plant having a capacity between 101 MW and 1000 MW is usually classified as a high capacity
plant.
iv. Super hydro plants
A super hydro plant has a capacity greater than 1000 MW.
4.5 ACCORDING TO TYPE OF FALL
i. Concentrated fall plants
In this type of plants the power house is located close to the dam or the weir so as to utilise the
entire created head as a concentrated fall.
ii. Divided fall plants
In this type of plants, the power house is located at a suitable distance away from the dam on the
downstream to utilise a steep fall available in the ground surface for increasing the operating head.
Chapter-5

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SITE SELECTION FOR HYDRO POWER PLANT
The following factors should be given careful consideration while selecting a site for a hydro-
electric power plant:
WATER AVAILABLE
The recorded observation should be taken over a number of years to know within reasonable,
limits the maximum and minimum variations from the average discharge. the river flow data
should be based on daily, weekly, monthly and yearly flow ever a number of years. Then the
curves or graphs can be plotted between tile river flow and time. These are known as
hygrographs and flow duration curves.
WATER-STORAGE
The output of a hydropower plant is not uniform due to wide variations of rain fall. To have a
uniform power output, a water storage is needed so that excess flow at certain times may be
stored to make it available at the times of low flow. To select the site of the Dam, careful study
should be made of the geology and topography of the catchment area to see if the natural
foundations could be found and put to the best use.
HEAD OF WATER
The level of water in the reservoir for a proposed plant should always be within limits throughout
the year.
DISTANCE FROM LOAD CENTER
Most of the time the electric power generated in a hydro-electricpower plant has to be used some
considerable distance from the site of plant. For this reason, to be economical on transmission of
electric power, the routes and the distances should be carefully considered since the cost of
erection of transmission lines and their maintenance will depend upon the route selected.
ACCESS TO SITE

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It is always a desirable factor to have a good access to the site of the plant. This factor is very
important if the electric power generated is to be utilized at or near the plant site. The transport
facilities must also be given due consideration.

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Chapter- 6
WORKING
Following are the working steps of a hydro power plant:-
i. Initially the water of the river is in Catchments Area.
ii. From catchments area the water flows to the dam.
iii. At the dam the water gets accumulated. Thus the potential energy of the water increases
due to the height of the dam.
iv. When the gates of the dam are opened then the water moves with high Kinetic Energy
into the penstock.
v. Through the penstock water goes to the turbine house.
vi. Since the penstock makes water to flow from high altitude to low altitude, Thus the
Kinetic Energy of the water is again raised.
vii. In the turbine house the pressure of the water is controlled by the controlling valves
as per the requirements.
viii. The controlled pressurized water is fed to the turbine.
ix. Due to the pressure of the water the light weight turbine rotates.
x. Due to the high speed rotation of the turbine the shaft connected between the turbine and
the generator rotates.
xi. Due to the rotation of generator the ac current is produced.
xii. This current is supplied to the powerhouse.
xiii. From powerhouse it is supplied for the commercial purposes.

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FIGURE 6.1: Working of hydro power plant

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Chapter-7
ADVANTAGES AND DISADVANTAGES OF HYDRO POWER PLANT
ADVANTAGES
i. Renewable source of energy thereby saves scares fuel reserves.
ii. Economical source of power.
iii. Non-polluting and hence environment friendly.
iv. Reliable energy source with approximately 90% availability.
v. Low generation cost compared with other energy sources.
vi. Indigenous, inexhaustible, perpetual and renewable energy source.
vii. Low operation and maintenance cost.
viii. Possible to build power plant of high capacity.
ix. Plant equipment is simple.
x. Socio-economic benefits being located usually remote areas.
xi. Higher efficiency, 95%to98%.
xii. Fuel is not burned so there is minimal pollution.
xiii. It's renewable - rainfall renews the water in the reservoir, so the fuel is almost always
there.
xiv. Hydropower is the least expensive method of generating electricity. The flowing water
is free and renewable by the water cycle.
xv. It is readily available. It can be controlled easily.
xvi. Hydropower can store energy. The water can be saved and managed efficiently,
depending on the seasons. It can also be used again and again.
xvii. It wastes less energy.
xviii. Dams control flooding and the water supply.
xix. Hydropower plants are dependable and last long. The maintenance costs are quite low.
xx. Hydropower’s source of energy is clean.
xxi. Hydro plants do not release pollutants into the air because they do not burn fuel.
xxii. Reservoirs can also offer leisure activities, such as swimming and boating
xxiii. No fuel charges.

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xxiv. Less supervising staff is required.
xxv. Maintenance & operation charges are very low.
xxvi. Running cost of the plant is low.
xxvii. The plant efficiency does not changes with age.
xxviii. It takes few minutes to run & synchronize the plant.
xxix. No fuel transportation is required.
xxx. No ash & flue gas problem & does not pollute the atmosphere.
xxxi. These plants are used for flood control & irrigation purpose.
xxxii. Long life in comparison with the Thermal & Nuclear Power Plant.
DISADVANTAGES
i. Loss of large land due to reservoir.
ii. Hydropower may become more expensive in the future. Licensing and assessing
dams is a long and expensive process.
iii. Wildlife habitats can be changed or destroyed. Fish, for example, may not be able to
swim upstream to reproduce. Their spawning and migratory patterns are disrupted.
iv. Hydropower can increase silting, alter water temperatures, and lower the amount of
dissolved oxygen in the water.
v. The initial cost of the power plant is very high.
vi. Generally, Such plant’s are located in hilly area’s far away from load center & thus
they require long transmission lines & losses in them will be more.
vii. Power generation by hydro power plant is only dependant on natural phenomenon
of rain .Therefore at the time of drought or summer session the Hydro Power Plant
will not work.
viii. It can be generated only in areas with heavy rainfall and sufficient supply of water.
ix. Hydel power generation stations are to be located in hilly mountainous terrains
where waterfalls as well as ideal sites for dams are located. In a region/country
without hills hydel power generation is not possible.
x. Building a dam affects the environment and wildlife of adjoining areas. Nearby
low-lying areas are always under the threat of floods.

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Chapter-8
CONCLUSION
In order to achieve a growth rate of 7-8 % as envisaged in National policy of India, it is also
required to tap all the small Hydro Power potential of the country. Hydro Power Project sector,
especially in view of the fact that Large Hydro power projects involve huge capital investment and
long gestation period which private partners do not afford to bear. The utilization of small Hydro
Power Potential is especially required in all states where the utilized potential is very low like in
MP and therefore optimum utilization of the same may set up an stepping up stone for achieving
self sufficiency in power sector in country.

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Chapter-9
REFERENCES
 Maps Of India
 Wikipedia
 Google Images
 Indian Energy Portal
 International Energy Association Data
 http://energy.gov/
 http://environment.nationalgeographic.com/environment/global-warming/hydropower-
profile/
 http://www.hydropower.org/
 WATER RESOURCES ENGINEERING by Dr. K.R. Arora published by Standard
Publishers Distributors.