3. Types of Power Plants
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1.Hydro Power Plant
2. Thermal Power Plant
3.Nuclear Power Plant
4. Diesel Power Plant
5. Gas Turbine Power Plant
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Hydro Power Plant – Major components
1. Reservoir : Water collected from the catchment area
is stored. Level of water in the reservoir
is called “Head race level”
2. Dam : Stores the excess water during rainy
season and regulates the outgoing flow
of water.
3. Spill ways : Excessive accumulation of water results
in instability of the dam. It is let out by
spill ways.
7. 4. Surge Tank : Small reservoir located in
between dam and turbine.
5 Water Turbine : Water under pressure is used to
convert the kinetic energy into
mechanical power .
6 Generator : Converts the mechanical energy into
electrical energy.
7. Draft Tube : Metallic pipe or concrete tunnel used
to let the water into river. Allow the
turbine to be located above the
“Tail race level”.
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8. WORKING PRINCIPLE OF HYDRO ELECTRIC POWER PLANT
Dam
Penstoc
k
Hydraulic
Turbine
Generat
or
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8
9. TYPES OF HYDRO ELECTRIC POWER PLANT
• Hydro electric power plant can be classified in the
following way.
(a) According to the availability of head
(i) High head power plants
(ii) Medium head power plants
(iii) Low head power plants
(b) According to the nature of the load
(i) Base load plants
(ii) peak load plants
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10. According to the quantity of the water available
(i) Run-of-river plant without pondage
(ii) Run-of-river plant with pondage
(iii) Hydro Electric Plant with storage
reservoirs.
(iv) Pump storage plants
(v) Mini and micro hydel plants
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11. HIGH HEAD POWER PLANTS
These plant works under a head of 100 m and above.
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12. Medium head power plants
These plants works under heads varying from 30 m to 100 m.
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13. Low head power plants
• Operates under a very low head
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16. PUMPED STORAGE PLANT
Water after working in turbines is stored in the
tailrace reservoir.
During the night time water is pumped back from
the tail to the head reservoir.
It works with better load factor.
A reversible turbine-pump unit is more profitable
in usage.
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18. 8 February 2023 18
Micro-hydel power plant
Micro-hydel power plant play a n important role in
remote rural areas and mountains.
It produces power output ranging from 5 kw - 100 kw.
It is either a run-off scheme or storage scheme.
Designed for low head turbines.
Minimum catchment area is enough.
Clean, non-polluting and renewable source of energy.
19. Steam boilers
What is a Boiler?
• Vessel that heats water to become hot water or
steam.
• At atmospheric pressure water volume increases
1,600 times.
• Hot water or steam used to transfer heat to a
process.
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20. Types of boilers
Fire Tube Boiler
Water Tube Boiler
Packaged Boiler
Fluidized Bed (FBC) Boiler
Stoker Fired Boiler
Pulverized Fuel Boiler
Waste Heat Boiler
Thermic Fluid Heater (not a boiler)
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21. 1. Fire Tube Boiler
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• Relatively small steam
capacities (12,000
kg/hour)
• Low to medium steam
pressures (18 kg/cm2)
• Operates with oil, gas or
solid fuels
23. 23
2. Water Tube Boiler
Used for high steam
demand and pressure
requirements
Capacity range of 4,500 –
120,000 kg/hour
Combustion efficiency
enhanced by induced draft
provisions
Lower tolerance for water
quality and needs water
treatment plant
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25. 25
3. Packaged Boiler
Oil
Burner
To Chimney
• Comes in complete
package
• Features
• High heat transfer
• Faster evaporation
• Good convective
heat transfer
• Good combustion
efficiency
• High thermal
efficiency
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26. 26
4. Fluidized Bed Combustion (FBC) Boiler
• Particles (e.g. sand) are suspended in high velocity air
stream: bubbling fluidized bed.
• Combustion at 840° – 950° C.
• Capacity range 0.5 T/hr to 100 T/hr.
• Fuels: coal, washery rejects, rice husk, bagasse and
agricultural wastes.
• Benefits: compactness, fuel flexibility, higher
combustion efficiency, reduced SOx & Nox.
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31. LA-MONT BOILER
It is a forced circulation, high pressure water tube steam boiler.
Circulation of water is maintained by a centrifugal pump which
is driven by steam turbine.
It consists of a steam separator drum, circulating pump,
distributor header, evaporator, economizer, superheater and
an air-pre heater.
Steam separator drum is located outside the boiler.
Capacity of the boiler is about 45 - 50 tonnes /hour of
superheated steam at a pressure of 130 bar at 540˚ C.
33. LOEFFLER BOILER
The high pressure feed pump draws water supplies to economizer and heat
is exchanged from hot exhaust gases to feed water.
Hot water then enters into the evaporating drum and evaporated into
saturated steam.
Then it is drawn by steam circulating pump.
Further it passes through the radiant and convective superheaters.
Here the steam is heated to the required temperature of about 500˚ C.
Its capacity is about 90-100 tonnes /hour at 150 bar.
35. It is high pressure, water tube drum-less boiler works on
forced circulation which is maintained by a centrifugal pump.
In this boiler, whole process of heating, steam formation and
super heating are done in single continuous tube.
Air preheater is used for preheating the air required for
efficient combustion in the furnace.
The capacity of this boiler is 150 tonnes/hour.
The pressure and temperature of this boiler is 210 bar & 650˚ C.
BENSON BOILER
41. • PROCESS de:
i) Represents adiabatic pressurization
ii) Raises the pressure from condenser pressure to
boiler pressure
iii) Slight rise in temperature of water during
compression process
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42. Process ea
• Represents constant pressure heat addition by the boiler to
the water
• Enthalpy increases by a large value during evaporation.
• The final condition of steam may be
1.wet
2.dry saturated or
3.superheated
depending upon the quantity of heat supplied to the boiler. 42
43. Process bc
• Represents isentropic expansion of steam in the prime
mover(turbine).
• Work is done by the steam and the pressure of the steam
falls down.
• In this process the heat energy of the steam is converted
into mechanical energy.
• During this process external work is also developed.
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44. Process cd
• It represents the condensation of steam coming out
of the turbine in the condenser .
• In this process, change of phase from vapour to
liquid phase takes place at constant temperature.
• During this process the pressure remains same.
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45. A Steam Power plant operating on Rankine cycle is supplied with dry
saturated steam at 40 bar . The exhaust takes place at 0.05 bar.
Determine
a) Rankine cycle efficiency
b) Work ratio
c) Specific Steam Consumption
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A power plant using steam as working fluid operates on
rankine cycle. The boiler and condenser pressures are 30 bar
and 1 bar. The condition of steam entering the prime mover is
dry and saturated. Find the thermal efficiency of the cycle
neglecting the feed pump work and considering the feed pump
work.
73. S.No
.
Thermal Power Plant Nuclear Power Plant
1 Large qty. of fuel is to be
transported
No fuel transportation
& handling
2 Ash disposal is a major issue No ash disposal
3 More number of workers
required
Less number is
sufficient
4 More land space is needed Less space is enough
5 Less efficient in full load
condition
More efficient in full
load condition
Thermal Power Plant Vs Nuclear Power Plant
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