Introduction about power plant engineering world and national scenario hydroelectric power plant diesel engine power plant maintenance

2. Unit 1
INTRODUCTION TO POWER
PLANTS
CO - Identify various componentsof Hydro, Steam, Gas, Diesel powerplant.

3. SYLLABUS :-
1.1 World and national scenario of demand and supply of energy.
1.2 Introduction to power plants: Their importance and types.
1.3 Hydroelectric power plant: Classification, General arrangement,
operating principle, advantages and limitations, Maintenance.
1.4 Diesel power plant: Introduction, components, advantages and
limitations, Diesel generating set, Maintenance.

4. 1.1 World and National scenario of demand and supply of energy.

5. Indian Energy Scenario-
• One National Grid: installed capacity of 330.86 GW
• India is the world's third largest producer and fourth largest consumer of
electricity.
• India's electricity sector is dominated by fossil fuels, and in particular coal,
which in 2016 produced about two thirds of all electricity.
49%
22%
14%
5%
10%
CONSUMPTION
INDUSTRY TRANSPORT OTHERS AGRICULTURAL RESIDENTAL

6. Resources of Energy and theirClassification
COAL
25.25%
OIL
37.37%
GAS
23.23%
NUCLEAR
6.06%
RENEWAB
LE
8.08%
1.Conventional or Non-renewable sources
a.Solid fuel - Wood, Coal, Cock etc.
b. Liquid fuels - petrol, diesel, keroseneetc.
c.Gaseous - natural, producer, blast furnacegas
d. Nuclear energy - U235 ,Tr232
2.Non-conventional or Renewable
sources
a. Hydro
b. Solar
c. Wind
d. Geothermal
e. Tidal
Energy Resources

7. Need for electricity is
increasing very rapidly
Electric power is power is of any industry
Is necessary to produce
electricity in large scale
and it should also be
economical
Electricity is used in our
day-to-day life for
lighting, heating, cooling,
lifting, cooking and so on
The large-scale power production
could be achieved only by means of
suitable power producing units like
power plants.
The generated power
must also be cost
effective, reliable and
fairly uninterrupted
Electric power is considered as the heart of
any industry
1.2 Importance of Power Plants :-

8. Classification of Power Plants
A) On the basis of source of energy :
• Hydroelectric power plants.
• Nuclear power plants.
• Gas turbine power plants.
• Diesel power plants.
• Tidal power plants.
• Wind power plants,
• Steam power plants
• B) On the basis of location:
• Central power station.
• Isolated power station

9. C) On the basis of conventional or non-conventional sources:
(i) Conventional sources:
• Thermal power plants (Steam, Diesel, and Gas).
• Hydro power plant.
• Nuclear power plant.
(ii) Non-conventional sources:
• Tidal power plant.
• Wind power plant.
• Solar power plant.
• Geo-thermal power plant.
D) On the basis of nature of load:
• Peak load plant.
• Base load plant.
• Stand-by plant

10. 1.3 Classification of Hydro-Electric power plants
A) According to the availability of Water head
High head plants (< 100 m e.g. Pelton Wheel )
Medium head plants ( 40m-100m e.g. Francis Water Turbine)
Low head plants ( > 40 e.g. Kaplan Water Turbine)
B) According to the nature of load
Base load plant
Peak load plant
C) According to the quantity of water available
Pump storage plant
Run –of- river plant
Hydroelectric plant with storage reservoirs
D) According to Small Hydroelectric Power Plats
Mini hydro plants (100KW-10MW)
Micro hydro plants (Below 100 KW)

11. 1.3 Hydroelectric Power Plants

12. 1. Working Principle
• In hydroelectric power plants, the potential energy of water is utilized to run the
hydraulic turbines, which in turn, runs an electric generator to convert the
mechanical energy of turbine into electric energy.

13. 2. Construction Features of Hydroelectric Power Plant
1. Reservoir :
• A reservoir is provided to store water during rainy season and supplies the same in dry
season.
• A large amount of water is collected during rainy season in a reservoir behind a dam.
• The water from the reservoir is used to run the hydraulic turbine.
2. Dam:
• Dam is constructed across a river to store the water. Therefore, it acts as a water reservoir.
• It is constructed with masonry or R.C.C. It provides necessary potential energy to nozzles
of a turbine.
• Top surface of water in dam is called as head race. It represents the gross head.
3. Trash rack:
• Trash rack is made up of steel bars. It is provided to prevent entry of debris into the intake
from dam.
• Any debris into the intake water pipe may damage the turbine runners or choke the nozzles
of an impulse turbine.

14. 4) Gate:
• The gate is provided for controlling of flow of water from reservoir to hydraulic turbine
through penstock.
• It is closed, when maintenance of system is required.
5) Surge tank:
• A surge tank is used to provide better regulation of water pressure in the system.
6) Spillway:
• A spillway is provided to discharge the flood water and to keep the level of water below
the designed maximum level in the reservoir. Thus, a spillway saves the dam from
damage during floods.
7) Water turbine:
• Hydraulic turbine converts hydraulic energy into mechanical energy.
• A Hydraulic Turbine consists of: Wheel, called as "runner" provided with a number of
curved vanes on its periphery.
• A guiding apparatus to direct the flow of water at inlet Of turbine. A water turbine can
be set horizontal or vertical. The factors considered are cost, building space, plant
layout etc.

15. 8) Waterway and Penstock:
• A waterway is used to carry water from the dam to the power house.
• Penstock is a circular pipe having very long length laid down from dam up to turbine
room.
9) Draft tube:
• A draft tube is a passage, which connects the exit from the turbine runner down to tail
race water.
• It supplements the action of runner of the reaction turbine by utilizing the remaining
kinetic energy of the water at discharge end of the runner.
10 )Tail race:
• it is a discharge canal, through which. Water is discharged from the turbine.
11) Power house:
• A power house consists of hydraulic and electric equipment's , where the water energy
is converted into electrical energy.
• Usually the power house is located underground

16. Layout of Hydroelectric Power Plants

17. • Working of Hydroelectric Power Plant:
1. Water from reservoir flows through penstocks to hydraulic turbine and
during the passage, its potential is converted into kinetic energy.
2. This high velocity jet of water strikes the hydraulic turbine vanes, where
its kinetic energy is converted into mechanical energy.
3. A generator coupled to hydraulic turbine converts the available
mechanical energy into electrical energy.
4. The speed of the turbine and generator depends upon the head, specific
speed and the power.
5. The electrical power generated is controlled by the governing
mechanism attached, to hydraulic turbine, which controls the quantity of
water to be supplied to the turbine according to the load on the system.

18. Need of Surge Tanks in Hydroelectric Power Plant :
• A surge tank is used to provide better regulation of water pressure in the
system.
• When the load on the turbine suddenly decreases, the gates admitting
water to the turbine are suddenly closed due to governor action. As a
result, it reduces the Water flow with sudden increase of pressure in the
penstock. This sudden rise of pressure in penstock is called as water
hammer.
• On the other hand, when the load on turbine suddenly increases, the
gates admitting water to turbine are suddenly opened. It causes the water
to rush from penstock into the turbine. Due to this, some portion of
penstock gets, evacuated for little time, which creates vacuum in the
penstock.
• Therefore, penstock is subjected to "positive pressure (water hammer) due
to decrease in load" and "to negative or vacuum pressure due to. increase
in load".

19. Advantages of Hydroelectric Power Plants
• No fuel charges.
• No fuel transportation problem.
• The cost of land is not a major problem, since the hydroelectric stations (power
plants) are situated far away from the developed areas.
• No standby losses.
• Low maintenance cost.
• Low running cost
• Short starting and stopping time
• No waste disposal problems
• Larger life of plant
• High efficiency
• Less supervision cost
• High reliability

20. Disadvantages of Hydroelectric Power Plants
• Hydroelectric power plants are usually located in hilly areas far away from
the Load Centre therefore, they require long transmission lines to supply
power. Therefore, the transmission losses are more, which increases the
cost of power/per unit transmitted.
• The initial cost of plant is very high.
• It takes considerably long time for the erection and installation of
hydroelectric power
• Power generation by the hydroelectric plant depends upon the quantity of
water available, which in turn, depends upon the natural phenomenon of
rain.
• Migration of land owners (people) and their rehabilitation is a big issue.

21. Selection of Site For Hydroelectric Power Plant
• Quantity of water available and method of storage.
• Availability of head and storage capacity.
• Distance of power station site from power demand centers.
• Details of soil bearing capacity and rocky foundation conditions.
• Availability of construction materials.
• Access to site for men and material.
• Availability of transport facilities.
• Cost of project and the period required for completion.
• Free from earthquake damage.
• Free from mineral deposits of harmful nature.
• Less possibility of sediment collection.

22. Preventive: maintenance for hydroelectric power plant
Drainage holes
Servomotor
Turbine shaft cover
Guide vane
mechanism
Operating Ring
1) Preventive maintenance is based on schedule inspections of plant and equipment's
2) its purpose is to minimize breakdown and excessive depreciation.
Monthly inspection Quarterly inspection Half yearly inspection Yearly inspection
Governor oil System
Ejector Cabinet
Servomotor
Feed back System
Gauges
Guide Vane And
Guide Bearing
Gauges are
re calibrated
Draft Tube
Emergency Side
Valve
Runner blades for
cavitation effect
Emergency slide
valve

23. 1.4 Diesel Engine Power Plant

24. Introduction to Diesel Engine Power Plant
• Diesel engine power plants are installed, where supply of coal and water is not
available in sufficient quantity or where standby sets are required for continuity of
supply such as hospitals, telephone exchanges, radio stations or cinemas.
• They are universally adopted to supplement hydroelectric or thermal power plants,
where standby generating plant is essential for starting from cold and under
emergency conditions.
• In several countries, demands for diesel power plants is increased for electric power
generation because of difficulties experienced in construction of new hydraulic plants
and enlargement of old hydro-plants.
• They are available in various range up to 50 MW.
• Diesel engine power plants used for electricity generation are more reliable as
compared to other power plants.

26. Diesel Engine Power Plant
1. Diesel engine:
• The diesel engine is main component to generate the mechanical energy from the heat energy,
which is obtained by burning diesel fuel. The engines are also known as C.I. (Compression
Ignition) engines.
2. Generator:
• It is coupled to output shaft of diesel engine.
• It is used to convert mechanical energy available at the .output shaft of diesel engine in to
electric power.
3. Air intake system:
• The air required for the combustion of fuel inside the diesel engine cylinder is drawn through
the air filter. The purpose of the filter is to remove dust from the incoming atmospheric air.
4. Exhaust system:
• This system leads the exhaust gases out of the engine and discharges them in the atmosphere.
• The exhaust gases coning out of the engine are very noisy. In order to reduce the noise, a
silencer is used.
• A catalytic converter is also provided in the exhaust system to keep the emissions within
prescribed limits.

27. 5. Cooling system:
• Only a part of heat released by burning of fuel is converted into useful work and rest of the
heat is passed through cylinder walls, piston rings etc. This heat may cause damage to these
parts of system.
• The temperature of the burning fuel inside the engine cylinder is 600 to 800°C.
• In order to lower this temperature, cooling is provided. For this purpose, cold water is
circulated around the engine. The water takes away the heat from engine and becomes hot. To
re-circulate the same water again for cooling, it is sent to cooling tower.
6. Fuel supply system:
• Fuel from the storage tank is pumped though a filter into a smaller tank, which is called as day
tank.
• This tank supplies the daily requirements of the diesel engine. The fuel is injected into the
engine cylinder by. a fuel injection pump through filter.
7. Lubrication system:
• The purpose of the lubrication system is to reduce the wear of the engine moving parts of
cylinder such as piston, shafts, valves must be lubricated.
• Lubrication system comprises of lubricating oil tank, oil pump and .oil cooler The lubricating oil
is -. drawn from the oil tank by pump and is passed through a filter to remove impurities. Then,
the clean lubricating oil is delivered to the points, which require lubrication.
• Lubrication also helps to cool the engine.

28. 8. Diesel engine starting system:
• Diesel engine used in diesel power plant is not self-starting.
• Diesel engine starting system is an arrangement to give the engine an initial start,
until firing starts and the unit runs with its own power.
• Small units are started manually by handles.
• Larger units use compressed air for starting. Here, high pressure air is admitted to
few cylinders, making them to act as reciprocating air motors to turn the engine
shaft over. The fuel is admitted to the remaining cylinders, which helps the
engine to start using its own power.
9. Governing system:
• The Governing system is used to maintain the speed of the engine constant at all
loads by adjusting and regulating the amount of fuel supplied to the engine.

29. Advantages of Diesel Engine Power Plants
• Simple in design and installation.
• Good response to varying loads without any difficulty.
• Stand-by losses are very less.
• They occupy less space.
• They can be started and put on load quickly.
• They require less quantity of cooling water.
• Overall capital cost is less than that of steam plants.
• Cost of building and civil engineering works is very low.
• These plants can be located near load centers.
• No problem of ash handling.
• Lubrication system is very economical as compared to steam power plants.
• Diesel power plants are more efficient than steam power plants in the range of
150 MW capacities.

30. Disadvantages of Diesel Engine Power Plants
1. High operating cost.
2. High maintenance cost
3 Capacity is limited. Maximum up to 150 MW.
4. Noise is a serious problem.
5.They cannot supply overloads continuously, whereas thermal power plants can
work under 25 % overload continuously.
6.Diesel power plants arc not economical, if fuel is to be imported.
7. Life of a diesel power plant (2 to 5 years) is very small as compared to thermal
power plants ( 25 to.30 years).

31. 1
For mobile power
generation, in
transportation systems
2
Capacities from 100
kW to 5000 kW.
3
Small scale industries,
small nursery stations.
4
They can be used as peak
load plants for some other
types of power plants
5
Small capacity central
stations
Applications of Diesel Engine Power Plants

32. Maintenance Procedure For Diesel Engine Power Plant
Maintain log sheets.
Check Periodically
Temprature,Pressure,Ele
ctrical Load.
Cleaning Of Fuel oil, Dirt
from filters.
Replace Filter
Periodically
Check temperature of
coolant , Lubricating
oil Exhaust gases
regular.
Do not run plant
below half load.
Ensure Radiator is
filled with sufficient
coolant.

33. THANK
YOU

34. Questions and Answers
• Questions for 2 Marks each
1. Name any four types of power plant.
2. List different types of Power plant.
3. State the importance of Power plants.
4. State any four limitations of diesel power plant.
5. State any four advantages of Diesel Power Plants.
• Questions for 4 Marks each
1. Classify hydroelectric power plant.
2. Draw typical layout of diesel engine power plant showing all system.
3. Explain with neat sketch operating principle of hydroelectric power plant.
4. Explain world and national scenario of demand and supply of energy.
5. List the advantages and disadvantages of Hydro electric power plant.
6. Draw general layout of Hydro-Electric Power plant showing all components.