2. Thermal Energy
• Thermal energy is the energy that comes
from heat
• This heat is generated by the movement of tiny
particles within an object
• The faster these particles move, the
more heat is generated
• Thermal energy is the total internal energy of
the atoms or molecules of a substance
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3. Thermal Energy
• Heat is thermal energy and is measured in the
same units as energy
• In the British system of units, thermal energy is
normally measured in British Thermal Units
(BTU)
• In scientific work, the usual unit of thermal
energy is the calorie (c) or the kilocalorie (C)
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4. Transfer of Thermal Energy as Heat
• Thermal Energy naturally moves from a substance with a higher
temperature to a substance with a lower temperature, until the
two substances have the same temperature
• The transfer of energy as heat can take place
via three processes:
i. conduction
ii. convection
iii. and radiation
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5. Conduction
• In conduction and radiation, energy transfers occurs
without the transfer of mass
• Conduction is the transport of thermal energy through an
object by a series of collisions between adjacent atoms,
molecules, or electrons
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6. Conduction
• If one end of a metal spoon is held in a pan on a stove, the
other end soon becomes hot. The energy from the stove
causes the molecules in the end of the spoon that is in the pan
to move faster, increasing the rate and size of their vibrations.
These molecules transfer some of their extra kinetic energy to
neighboring molecules and these, in turn, affect their neighbors.
• Therefore, the temperature of the entire spoon increases. If the
pan is kept at a constant temperature, after some time the pan
and the spoon will have the same temperature. No smart
person would pick up this spoon without a potholder. The 6
7. Convection
• Heat is transferred through a substance through currents
• This occurs in fluids (liquids AND gases)
• Convection currents are caused by heating of a liquid or
gas, the liquid or gas rises, then cools and falls. This
occurs in the mantle of the earth And in the atmosphere
• Most of our weather patterns are the
result of convection currents in the
atmosphere
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8. Radiation
• Radiation is heat transfer by electromagnetic waves
• These wave may pass through all states of matter
• This energy is often called radiant energy
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9. Thermal Power Plant
• A Thermal Power Plant converts the heat energy of coal
into electrical energy
• Coal is burnt in a boiler which converts water into steam
• The expansion of steam in turbine produces mechanical
power which drives the alternator coupled to the turbine
• Thermal Power Plants contribute maximum to the
generation of Power for any country
• In thermal generating stations coal, oil, natural gas etc. are
employed as primary sources of energy
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10. Working Principle of Thermal Power
Plant
• Firstly the water is taken into the boiler from a water
source
• The boiler is heated with the help of coal
• The increase in temperature helps in the transformation of
water into steam
• The steam generated in the boiler is sent through a steam
turbine
• The turbine has blades that rotate when high velocity
steam flows across them
• This rotation of turbine blades is used to generate
electricity
• A generator is connected to the steam turbine
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11. History
• The initially developed reciprocating steam engine has been
used to produce mechanical power since the 18th Century,
with notable improvements being made by James Watt
• When the first commercially developed central electrical
power stations were established in 1882 at Pearl Street
Station in New York and Holborn Viaduct power station in
London, reciprocating steam engines were used.
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12. Layout Of Thermal Power Plant
• MAIN EQUIPMENTS
• Coal handling plant
• Pulverizing plant
• Boiler
• Turbine
• Condenser
• Cooling towers and ponds
• Feed water heater
• Economizer
• Air preheater
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13. Thermal Power Plant
Coal Handling Plant
• The function of coal handling
plant is automatic feeding of
coal to the boiler furnace
• A thermal power plant burns
enormous amounts of coal
• A 200MW plant may require
around 2000 tons of coal
daily
Pulverizing Plant
• In modern thermal power
plant, coal is pulverized i.e.
ground to dust like size and
carried to the furnace in a
stream of hot air
• Pulverizing is a means of
exposing a large surface
area to the action of oxygen
and consequently helping
combustion
• Pulverizing process consists 13
14. Thermal Power Plant
Boiler
• The function of boiler is to
generate steam at desired
pressure and temperature by
transferring heat produced by
burning of fuel in a furnace to
change water into steam
Condenser
• The surface condenser is a
shell and tube heat
exchanger where cooling
water flows through tubes
and exhaust steam fed into
the shell surrounds the
tubes. as a result, steam
condense outside the tubes
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15. Thermal Power Plant
Cooling Towers And Ponds
• A condenser needs huge
quantity of water to condense
the steam
• Most plants use cooled
cooling system where warm
water coming from condenser
is cooled and reused
• Cooling tower is a steel or
concrete hyperbolic structure
with the height of 150m
Feed Water Heater
• Feed water heating improves
overall plant efficiency
• Thermal stresses due to cold
water entering the boiler
drum are avoided
• Quality of steam produced by
the boiler is increased
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16. Thermal Power Plant
Economizer
• Flue gases coming out of the
boiler carry lot of heat
• An economizer extracts a part
of this heat from flue gases
and uses it for heating feed
water
• Saving coal consumption and
higher boiler efficiency
Air Preheater
• The function of air pre-
heaters is to preheat the air
before entering to the
furnace by utilizing some of
the energy left in the flue
gases before exhausting
them to the atmosphere
• After flue gases leave
economizer, some further
heat can be extracted from
them and used to heat
incoming heat
• Cooling of flue gases by 20
16
17. Waste Generated And Their Control
Ash Handling Plant
• The ash from the boiler is
collected in two forms-
• Bottom ash(slurry): It's a
waste which is dumped
into ash pond
• Fly ash: Fly ash is
separated from flue gases
in esp
Water Handling Plant
• Water in a Power Plant is
used for:
• Production of Steam- for
rotating turbine
• Cooling Purpose- For cooling
of various equipment
• Water is recycled and used
for various purpose: Raw
Water For Cooling Purposes
Steam Condenser Raw Water 17
18. Thermal Power Plant
Advantages
• The fuel used is quite cheap
• Less initial cost as compare
to other generating stations
• It can be installed at any
place irrespective of the
existence of coal
• The coal can be transported
to the site of plant by rail or
roads
Disadvantages
• It pollutes the atmosphere
due to producing large
amount of smoke and fumes
• Higher maintenance cost
and operational cost
• Huge requirement of water
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19. Thermal Power Plants in Pakistan
• Kot Addu Power Company: 1,600MW Capacity, Multi
Fuel-Fired Thermal Station
• Hub Power Company: 1,292MW Capacity,
Furnace Oil Fired Plant
• Hubco Narowal Power Plant: 225MW Capacity, Furnace
Oil Fired Plant
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21. Introduction
• Tides are the waves caused due to the gravitational pull
of the moon and also sun(though its pull is very low)
• The rise is called high tide and fall is called low tide
• This building up and receding of waves happens twice a
day and causes enormous movement of water
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22. Tidal Turbines
• Tidal Turbines: Tidal turbines use similar technology to
wind turbines, although their blades are much shorter
and stronger
• So a good way to think of them is as underwater
windmills.
• It make use of the kinetic energy of moving water to
power turbines, in a similar way as windmills use moving
air. This method is gaining in popularity because it’s
removable, it can be scaled up gradually (from one
device, to an array, to a larger farm), and has lower
potential costs and ecological impact (compared to
barrages) 22
23. Tidal Barrages
• Tidal Barrages: Tidal barrages are very similar to the
Dams in hydroelectric plants, except that they are much
larger as they are built across an estuary or bay
• Barrages make use of the potential energy in the
difference in height– between high and low tides
• They are essentially dams across the full width of a tidal
estuary – or the mouth of a river that has a free-flowing
connection to the ocean
• Barrages have very high costs, a worldwide shortage of
viable sites and associated environmental concerns
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24. Tidal Lagoons
• Tidal Lagoons: Tidal Lagoons are similar to barrages but
have a much lower cost and impact on the environment
• Tidal Lagoons can be constructed as self-contained
structures not extending fully across an estuary
• Some suggest this may reduce both costs and overall
impacts
• They can be configured to generate continuously, which
is not the case with barrages
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26. Advantages
• It is an inexhaustible source of energy
• Tidal energy is environment friendly energy and doesn't
produce greenhouse gases
• As 71% of Earth’s surface is covered by water, there is
scope to generate this energy on large scale
• We can predict the rise and fall of tides as they follow
cyclic fashion
• Efficiency of tidal power is far greater as compared to
coal, solar or wind energy
• Its efficiency is around 80%
• Although cost of construction of tidal power is high but
maintenance costs are relatively low
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27. Disadvantages
• Cost of construction of tidal power plant is high
• There are very few ideal locations for construction of
plant and they too are localized to coastal regions only
• Intensity of sea waves is unpredictable and there can be
damage to power generation units
• Influences aquatic life adversely and can disrupt
migration of fish
• The actual generation is for a short period of time. The
tides only happen twice a day so electricity can be
produced only for that time
• Frozen sea, low or weak tides, straight shorelines, low
tidal rise or fall are some of the obstructions
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28. Marine Life Disturbance
• Studies to date suggest that local environmental impacts
are likely to be minor, but further research is required
into device-environment interactions, particularly the
impact of tidal stream energy generators on flow
momentum
• Although the generators create no noise audible to
humans, they do create “modest” noise underwater
• Manufacturers maintain that this is important to help
marine wild-life have an awareness of the presence of
the turbine
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29. Legislation
• Section 4(e) of the FPA directs the Commission to give
equal consideration to the purposes of power and
development, energy conservation, fish and wildlife,
recreational opportunities, and preservation of
environmental quality “in deciding whether to issue a
license.” (National Wildlife Federation)
• Similarly, sections 10(a) and 10(j) are prefaced with the
direction that “all licenses issued under this subchapter”
shall include the conditions required by sections 10(a)
and 10(j).
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30. Tidal Energy
• Tidal Electricity - Like other forms of Energy, the main
usage of Tidal Energy is in the generation of Electricity
• In 1966, Électricité de France opened the Rance Tidal
Power Station, located on the estuary of the Rance
River in Brittany
• It was the world's first tidal power station
• Tidal Energy is being used in France to generate 240
MW of Tidal Electricity at very low costs
• Energy Storage - Tidal Energy can also be used as a
store of Energy. Like many of the hydroelectric dams
which can be used a large Energy Storage, so Tidal
Barrages with their reservoirs can be modified to store 30
31. Tidal Power In Pakistan
• Tidal power has not yet been operational in Pakistan
compared to other renewable energy technologies, but
in near future it may play a key role. Some think that
tidal power plants in coastal creeks of Pakistan can
serve the energy crisis conundrum up to some level
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