This document provides information about hydropower, including: - Hydropower harnesses the kinetic energy of moving water to generate electricity through turbines connected to generators. - The main types of hydropower systems are impoundment, diversion, and pumped storage. Impoundment uses dams to store water in reservoirs, while diversion channels water without dams. Pumped storage pumps water between reservoirs. - Large hydropower plants supply electricity to many consumers, while small and micro plants power individual needs. Hydropower provides clean energy but building large dams is expensive and can negatively impact communities and ecosystems. Proper management is needed to address issues.

1. {
Exploring Hydropower
SUBMITTED BY : APOORVA JAIN

2. What is Hydropower ?
Hydropower refers to energy, mostly electric,
which is derived from water in motion. This
power
is harnessed and used to drive mechanical
devices.
The main advantage of this form of energy is that
it is clean and renewable. Hydropower plants are
actually based on a rather simple concept --
water
flowing through a dam turns a turbine, which
turns a generator.

3. Types of Hydropower
—Impoundment
An impoundment facility, typically a large hydropower system,
uses a dam to store river water in a reservoir. The water may be
released either to meet changing electricity needs or to maintain a
constant reservoir level.
—Diversion
A diversion, sometimes called run-of-river, facility channels a
portion of a river through a canal or penstock. It may not require
the use of a dam.
—Pumped Storage
When the demand for electricity is low, a pumped storage facility
stores energy by pumping water from a lower reservoir to an upper
reservoir. During periods of high electrical demand, the water is
released back to the lower reservoir to generate electricity.

4. Impoundment
Diversion
Pumped Storage

5. Harnessing Water Power

6. 0 200 400 600 800 1000 1200
Sweden
Japan
Venezuela
India
Norway
Russia
United States
Brazil
Canada
China
2015 2014 2013
2012 2011 2010
Hydroelectric Generation by Country
Billion kilowatt-hours

7. Hydroelectric dam

8. Turbine generator Generator

9. Advantages
• Clean Energy Source
• Domestic Energy Source
• Generally Available As Needed
• Provides Recreational Opportunities
• Water Supply and Flood Control
• Once a dam is constructed, electricity can be produced at
aconstant rate.
• If electricity is not needed, the sluice gates can be shut,stopping
electricity generation.
• The water can be saved for use another time when electricity
demand is high.
• Dams are designed to last many decades and so can contribute to
the generation of electricity for many years /decades.
• The lake that forms behind the dam can be used for water sports
and leisure / pleasure activities. Often large dams become tourist
attractions in their own right.
• The lake's water can be used for irrigation purposes.

10. Power Plant Efficiency
Most thermal power plant are about 35% efficient. For every
100 units of energy that go into plants , 65units are lost as
one form of energy is converted into other other forms .most
of the lost energy is in form of heat from friction and heat
that escape the system.35 units are left to do usable works.

11. Possible Environmental Impacts
• Fish Population
• Quality and Flow of Water
• Ecosystems of Rivers and Streams
Other Disadvantages
• Dams are extremely expensive to build and must be built to a
very high standard.
• The high cost of dam construction means that they must operate
for many decades to become profitable.
• The flooding of large areas of land means that the natural
environment is destroyed.
• People living in villages and towns that are in the valley to be
flooded, must move out. This means that they lose their farms and
businesses. In some countries, people are forcibly removed so that
hydro-power schemes can go ahead.
5. The building of large dams can cause serious geological damage.

12. Flow Chart
Social
issues
Environmental
impacts
Hydropower
benefits
Potential
impact
Economic
impacts
Draw backs

13. SOCIAL ISSUES
—Relocating people from the reservoir area is the most challenging
social aspect of hydropower,leading to significant concerns regarding
localculture, religious beliefs, and effects associated with inundating
burial sites. While there can never be a 100 percent satisfactory
solution to involuntary resettlement, enormous progress has been
made in the way the problem is handled.
Environmental Impacts
—Hydroelectric power includes both massive hydroelectric dams and
small run-of-the-river plants.Large-scale hydroelectric dams continue
to be built in many parts of the world (including China and
Brazil),but it is unlikely that new facilities will be added to theexisting
U.S. fleet in the future.Instead, the future of hydroelectric power in
the United States will likely involve increased capacity at current
dams and new run-of-the-river projects. There
are environmental impacts at both types of plants.

14. SIGNIFICANCE
Hydropower stands as the most significant renewable energy source. It
uses the single but very powerful energy force of moving water. By some
comparison, it competes with the energy produced by fossil fuels and
nuclear power, but is considered much cleaner and more simplistic.
Hydropower remains popular even in third-world countries, which do
not have the resources to build expensive nuclear generating stations.
Hydropower does not pollute the atmosphere or environment.
Facts
• —Hydropower uses the energy of moving water for a variety of useful
applications. Hydroelectricity generates electricity by harnessing the
gravitational force of falling water.
• —In 2006, hydroelectricity supplied around 20% of the world’s electricity
• —Most hydroelectric power stations use water held in dams to drive
turbines and generators which turn mechanical energy into electrical
energy.
• —The largest hydroelectric power station in the world is the Three
Gorges Dam in China.

15. Economic Impacts
Large dams have long been promoted as providing "cheap"
hydropower and water supply. Today, we know better. The costs and
poor performance of large dams were in the past largely concealed by
the public agencies that built and operated the projects. Dams
consistently cost more and take longer to build than projected. In
general, the larger a hydro project is, the larger its construction cost
overrun in percentage terms.
Environmental Impacts
—The IHA (International Hydropower Association) Working Group on
Environmental Impact
Assessment (EIA) calls for impact assessment to be an integral part of
the multidisciplinary planning approach, and to include a strong
element of public consultation. EIAs should cover both positive and
negative impacts both upstream and downstream of a proposed
project.

16. SIZES OF HYDROELECTRIC
POWER PLANTS
Facilities range in size from large power plants that supply many
consumers with electricity to small and micro plants that individuals
operate for their own energy needs or to sell power to utilities.
Large Hydropower
Although definitions vary, DOE defines large hydropower as facilities
that have a capacity of more than 30 megawatts (MW).
Small Hydropower
Although definitions vary, DOE defines small hydropower as projects
that generate 10 MW or less of power.
Micro Hydropower
A micro hydropower plant has a capacity of up to 100 kilowatts. A
small or micro-hydroelectric power system can produce enough
electricity for a home, farm, ranch, or village.

17. Case study
Indonesia - Bakaru
Key project features
Category: Reservoir drawdown and sluicing Mechanical excavation Pressure flushing
Reservoir volume: 8.28 Mm3 (original)
Installed capacity: 126 MW
Date of commissioning: 1991
Bakaru hydropower plant makes a significant contribution to power supply in its region, making it
difficult to implement drawdown and sluicing, because this would involve the temporary shutdown of
the powerhouse. Pressure flushing and mechanical excavation are implemented as additional measures
to clear sediment.
The Bakaru hydropower plant represents the major power supply source in the South Sulawesi region
in Indonesia, where the total installed capacity was about 400 MW in 2008. The Bakaru dam, completed
in 1991, is located on the Mamasa River, as shown in figure 1. The Bakaru plant’s current installed
capacity is 126 MW (comprising two 63 MW Francis turbines), operating under a maximum head of
322.2 m, with a design discharge of 45 m3/s.
The project consists of a 16.5 m high concrete gravity dam with a crest length of 122.5 m, fitted with two
steel roller flushing gates, two steel roller regulating gates and four radial spillway gates. The maximum
operating elevation is 615 masl and the minimum operating elevation 612 masl. The original reservoir
volume was 8.28 Mm3 with a live storage capacity of 2 Mm3. The flood discharge capacity of the
spillway is 2,500 m3/s. The dam is located at the upper edge of a significant drop in the river, where the
original river bed slope (prior to sedimentation) was 1/570 immediately upstream of the dam, increasing
to 1/5.8, with large amounts of rock immediately downstream of the dam

18. Indonesia -
Bakaru

19. Hydrology and sediment
The catchment area of 1,080 km2 upstream of Bakaru hydropower plant produces an annual average mean
flow of 1,794 Mm3, with an annual coefficient of variation of 0.22. The small variability in annual flows, as
well as the mean distribution of monthly flows, are shown in the hydrographs in figure 3.
The sediment load in the Mamasa River at Bakaru is currently estimated as 988,000 t/yr (760,000m3/yr),
which is equivalent to a specific sediment yield of 915 t/km2/yr. The bed load largely consists of sand, and
the suspended load contains silt and clay. The catchment conditions are poor and erodibility high. The
hydrographs for water and sediment discharge for three monitoring events, cumulative sediment inflow
and a sediment rating curve
Sediment problems
The main sediment challenges experienced at the project are storage loss and abrasion of turbines. By
2000, storage loss amounted to about 70 per cent of the total original storage, and then stabilised, as
shown in figure 7, at about 73 per cent. The live storage was affected, but to an unknown degree.
Sediment management efforts were intended to keep the reservoir volume stable at about 27 per cent of
the original total storage volume. Damage to the turbines, as shown in figure 8, was significant due to
abrasion by sediment flowing through the system.
The principal reasons for the high rate of sedimentation at Bakaru is that the actual sediment yield is
much greater than that estimated during the design phase. The sediment yield used in the design was
133,000 m3/yr (about 172,900 t/yr), which amounts to a specific sediment yield of 160 t/km2/yr. The actual
sediment load was later estimated at 760,000 m3/yr (about 988,000 t/yr), amounting to a specific sediment
yield of 915 t/km2/yr. The sediment yield was therefore underestimated by a factor of five to six.
The project was originally designed to manage sediment through drawdown sluicing. The standard
operating procedure as regards drawdown sluicing has not been implemented consistently, due to the
fact that Bakaru supplies a significant amount of power to South Sulawesi. Dispatching needs overruled
the implementation of sediment management procedures, as indicated further on in this case study.

20. Sediment management strategies
The project was originally designed to execute sluicing of sediment whenever the discharge in the river
exceeded 400 m3/s. However, the low frequency of these flood magnitudes resulted in the frequency of
sluicing not being sufficient. The standard operating rule (SOP) was changed in 2002 to sluice the
reservoir whenever discharges in the Mamasa River exceeded 200 m3/s. Figure 9 illustrates the operating
rule for a precipitation event in November 2008. The SOP decision process is shown schematically in
figure 10.
In many cases when the reservoir could have been sluiced, the dispatch centre chose not to, giving priority
to power generation. Figure 11 illustrates that during the period 2000 to 2009, there were 24 events when
discharge exceeded 200 m3/s, but sluicing was only implemented nine times, and the duration of the
sluicing events were limited to about four hours, which is not sufficient. When sluicing, the flushing gates
were sometimes only partially opened to maintain the water level for concurrent power generation. In
such cases, pressure flushing rather than drawdown sluicing was implemented.
The difference in the amount of sediment that can be removed when the gates are fully opened and when
they are not fully opened is illustrated by the following example. On 4 February 2000, sediment was
sluiced and power plant operation was completely suspended. This amounted to 863,000 m3 of sediment
being sluiced while the daily inflow of water was 584.7 m3/s. Conversely, on 5 April 2001, a pressure
flushing operation was carried out while simultaneously generating power; ie the water surface elevation
was kept high while the gates were only partially opened. This resulted in removing about 256,840 m3 of
sediment, while the average water inflow to the reservoir was 100 m3/s. Sluicing was not performed when
the flows exceeded 200 m3/s, but pressure flushing was executed at a lower flow. The events in 2001, 2005,
and 2009 were likely to have been pressure flushing events that did not follow the standard operating
procedure to sluice. The relationship between the number of events when the discharge exceeded 200 m3/s
and the number of sluicing events performed can be observed in the graphs.
After sedimentation problems became significant, the sluicing of sediment was complemented by
dredging. Comparison of achieved and contracted mechanical excavation amounts of sediment.

21. Region : Rajasthan
Facing : west
Materials used: bamboo for tv panel and furniture, mud for
walls,fabric for walls ,coconut husk flooring,hemp in ceiling