non-conventional energy sources & interconnected power · pdf filemr. nitin s. patil...

Mr. Nitin S. Patil

Electrical Engineering Department

Sanjay Ghodawat Polytechnic, Atigre

Non-Conventional Energy Sources & Interconnected Power System

SGP-Atigre Electrical Engg.Dept.

Mr.N.S.Patil 2

Topic Number 7

Non-Conventional Energy Sources &

Interconnected Power System

Hours = 04 Marks = 08

INDEX

Sr.No. Particulars Page No.

1 Non-Conventional Energy Sources 2 to 4

2 Wind Power Plant 5 to 10

3 Solar Power Plant 11 to 19

4 Tidal Power Plant 20 to 22

5 Bio Gas Power Plant 23 to 25

6 Inter connected Power System 26 to 33


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Non-Conventional Energy Sources


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1. List any four sources of conventional energy & List out any two

conventional sources and non-conventional sources of energy.

Answer: Following are the conventional energy sources.

Water or Hydro power plant.

Fuel used as a high grade coal, Thermal power plant.

Fuel used as a natural oil and gas.

Fuel used as a diesel (Diesel power plant).

Atomic or Nuclear Energy (Nuclear power plant).

Non Conventional Energy Sources:

The sun energy.

The wind energy.

Geothermal Energy.

Ocean Tides, Waves or thermal energy.

Biomass energy

2. Compare conventional energy sources with non-conventional energy

sources.


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3. State any four limitations in using renewable energy resources.

Following are the Limitations of renewable energy resources:

Capital cost per MW of power plant is more.

Its reliability is less.

No firm power.

Its efficiency is less.

Generally, its generating capacity is limited.

Technology to generate electricity from renewable sources is not fully

developed.

There is limitation on site selection.

There is no guaranty that power is generated during peak hours or whenever

needed.

Power generation is not phase with demand.

Cost per unit is high in some power plant.

4. State and explain the advantages of conventional energy sources over

non-conventional energy sources.

Answer:

Advantages of conventional energy sources over non-conventional energy

sources:

Generating capacity is more.

Reliability is more.

Firm power is more.

Efficiency is more.

Capital cost per mega watt is less.

Air Pollution is more.

Not depends on atmospheric condition.


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5. “The non- conventional sources were known to man since early days,

still they were not developed” comment and give reasons.

Answer: The non- conventional sources were known to man since early days,

developed because of following reason:

Initial cost per MW is high.

No firm generating capacity.

Its efficiency is low.

There is limitation on site selection in some cases.

Generating capacity is less.

There is no guaranty that power is generated during peak hours or whenever

needed.

Power generation is not phase with demand.

Cost per unit is high.

It is not reliable.

Life is less.


Mr.N.S.Patil 7

Wind Power Plant

1. List the major locations of wind mills in Maharashtra.

Answer:

2. Basic Principal of Wind Power Plant:

3. State the factors for selection of site for wind mills. Explain briefly.

Mention the specialty of wind mill generator.

Answer:

1. The Factors for selection of site for Wind Mills:

The site should be selected where winds are strong i.e. where pressure

of wind is high and there is continuity (10-15km/hr) and above.


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It is better to choose a site near the seashore (coastal area).

Winds turbines are also installed OFF shore (in ocean) OFF shore

wind turbine generate more electricity than those on land because the

wind at sea is typically stronger and more constant than ON shore.

Wind pressure is also high in hilly area so wind turbines are located in

hilly area.

Site should be convenient for transportation facility.

The cost of land should be low.

Plant must be installed on tall towers (45m to 149 m) as wind pressure

is available with higher velocity.

2. The specialty of wind mill generator:

Typically wind turbines generate electricity through asynchronous

machine that are directly connected to Electrical Grid. The wind turbine

generator is equipped with a double-fed three-phase induction generator. The

advanced power electronics (IGBT Converter) ensure that the generator

works with high efficiency over the entire speed range. A heating winding is

installed to prevent damage to the generator due to damp In addition; there

are sensors to monitor the temperature in the generator. The generator and

the power electronics are cooled by water-air heat exchanger.

Or

In a turbine generator, magnets spin around a coil to produce current.

The faster the magnets spin, the more current is induced in the coil. To make

up for a direct drive generator's slower spinning rate, the diameter of the

generator's rotor is increased hence containing more magnets which lets it

create a lot of power when turning slowly. To reduce the generator weight

some constructors use permanent magnets in the generators rotor, while

conventional turbine generators use electromagnets fed with electricity from

the generator itself. To enhance their competitiveness, the design of smaller

generators with improved torque is still an active research area.


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3. Draw the neat labeled diagram of wind mill and state its applications.

Fig: Wind Mill

Or (Draw Belo Figure)


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Function of wind power/energy conversion system each part:

Rotor /Blade/Aero-turbine: Blade extracts significant power from the

wind. Which convert the force (K.E.) of the wind into the rotary motion to

generate useful mechanical power

OR

Rotor blades: The blades are the sails of the system, when the wind forces

the blades to move, it has transferred some of its energy to the rotor.

Hub: Hub of the wind turbine is those components which connects the blade

to the main shaft and ultimately to the rest of drive train.Hubs are generally

made up of steel.

Main Shaft (Low speed shaft): It is provided for transfer of torque from the

rotor blade to the rest of the drive train. It also supports weight of rotor.

Speed of the shaft is low, is about 30 to 60 rotations per unit.

High speed shaft: It is connected to generator via-gearbox, Speed of the

wind turbine is low; gearing arrangement increases the speed of rotation to

the level as per design. E.g. 1500 rpm for 50 Hz frequency and 1800 rpm for

60 Hz frequency necessary to generate electricity with the help of generator.

Gear box is one of the heaviest and most expensive components in wind

turbine.

Coupling: Coupling is used to connect shaft together between main shaft

and gear box & between gear box output and the generator.

Break: The break is fitted to stop the wind turbine. By applying break When

dangerously strong wind are approaching i.e. when wind speed exceeds55-

65 miles per hour to avoid damage OR In case of emergency to stop the

rotation of turbine OR When the turbine is taken down for maintenance.


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Yaw Controller: It rotates the blade towards the face into the wind direction

i.e. it detects the direction of wind. OR Yaw system: they perform the task

of orienting the rotor in the direction of wind.

Pitch Controller: The pitch controller adjusts automatically the pitch of

each blade i.e. blade can be rotate to increases efficiency in low wind and to

decrease in very strong winds (to protect the wind turbine).

Electrical Generator: Function of generator is to convert mechanical

energy produced by wind turbine into electrical energy.

Anemometer: It’s a wind direction sensor with digital display. Used in

areas where AC power is not available. Monitors wind speed and store max

and average value.

Controller: Controller takes data from anemometer (which measures the

wind velocity): The controller sends: Wind direction & wind speed. The

controller protect wind turbine from abnormal wind conditions, excessive

temperature rise of generator, electrical fault etc.

Nacelle: Necelle cover provides weather protection for the principle

components of the wind turbine. OR Nacelle: It is structure that houses all of

the generating components like-gearbox, rotor shaft and brake assembly etc.

Tower: A tower is needed to elevate the blades to where the wind is

stronger and smoother. Towers are supports to raise the main part of the

turbine up in the air.


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Application:

1. Wind energy is used to generate electrical energy in large scale with the help

of commercial wind turbine.

2. Wind energy can be generated electrical energy in small scale for residential,

small commercial, hotels and hospitals etc.

3. For pumping the water from well.

4. Wind energy can be used for grinding purpose.

4. What are the basic requirements of locating wind power plant?

Answer: The basic requirement of locating Wind power plant:

The site should be selected where winds are strong i.e. where pressure of

wind is high and there is continuity (10-15km/hr) and above.

It is better to choose a site near the seashore (coastal area).

Winds turbines are also installed OFF shore (in ocean) OFF shore wind

turbine generate more electricity than those on land because the wind

velocity /pressure inside the sea (OFF Shore) is typically stronger and more

constant than ON shore.

Wind pressure is also high in hilly area so wind turbines are located in hilly

area.

Site should be convenient for transportation facility.

The cost of land should be low.

Plant must be installed on tall towers (45m to 149 m) as wind pressure is

available with higher velocity.

Nearby grid should be available.


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5. State any four advantages of wind energy system

Answer:

1. Fuel is freely available.

2. Wind energy is inexhaustible.

3. There is no air pollution.

4. No fuel transportation cost.

5. No space is required to store fuel.

6. No need on treatment on fuel.

7. No waste disposal cost and problem.

8. Less manpower is required per MW.

9. Layout is simple.

10. Time required for completion of power plant project is less.

11. Space required is less and space around the tower can be utilized for farming

or storage.

12. It works automatically i.e wind turbine operates automatically.

13. Technology is simple and robust.

14. Generating cost per unit is less and is goes on decreases day by day.

15. Maintenance cost is less.

16. Type of source is renewable.


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6. Give any four limitations (or disadvantages) of wind energy.

Answer: Following are the Limitations of wind energy

1. Initial cost per MW is high.

2. The source of power (wind) is unsteady and unreliable.

3. No firm generating capacity.

4. In case of low wind, power cannot be generated.

5. Its efficiency is low (20% -30%).

6. There is limitation on site selection.

7. Transportation cost of wind tower and accessories is high.

8. It disturbs load traffic during transportation of heavy wind tower and

accessories.

9. Installation cost of wind tower is high and difficult (because of WPP are

generally in hill area and transportation of heavy urban and other equipments

is difficult to reach up to the side.

10. It produces noise.


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Solar Power Plant

1. Define Photovoltaic Effect? What is mean solar cell? State working of

solar cell with neat sketch

Answer:

a. Photovoltaic Effect:

The Photovoltaic effect is defined as the generation of an electromotive

force as a result of absorption of ionizing radiations.

b. Solar Cell:

Which converts solar energy (heat energy) directly into electrical energy

(DC) is called as solar cell.

Or

Energy Conversion devices which are used to convert sunlight into

electricity by the use of photo-voltaic effect are called solar cells.

Silicon Solar Cell consists of a thin slice of single crystal P-Type Silicon

Material up to 2 cm2 into which a very thin (0.5 micron) layer of N-Type

Material is diffused.


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c. Working:

Solar cell operates on principle of Photo-voltaic Effect which is process of

generating an emf (DC) when it absorbs sun radiations.

Or

Solar cell works in following steps:

Photons in sunlight hit the solar panel and absorbed by semiconducting

material (such as silicon).

Electrons (negatively charged) are knocked loose from their atom causing an

electric potential difference.

Thus converts solar energy into electrical energy without any waste

products.

Or

d. Working:

Photovoltaic cell is small semi conductor device which has light sensitive P-

N junction. It made up semi-conducting material and these cells are light

sensitive. The P- Type layer is thick while the N-Type Layer is thin. When

trivalent impurity is added, P-Type semiconductor is obtained. When

sunlight strikes the N-type Layer, some of the waves of light energy

penetrate up to the P-Type layer. When photons from the Sunlight energy

are absorbed in semi conductor, and sunlight energy is greater than energy

gap, electron-hole pairs are formed. Electrons are released from N-Type

material and holes are created in P-type material electrical circuit is

completed and flow of current takes place. Photo voltaic cell system

converts solar energy directly into electrical energy without any waste

products.


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e. Material Used:

Silicon solar cell consists of a thin slice of single crystal P-type silicon

material up to 2 cm2 into which a very thin (0.5 micron) layer of N-type

material is diffused.

OR (Any one material name is expected)

Mono-crystalline silicon.

Polycrystalline silicon.

Amorphous silicon.

Cadmium telluride.

Copper indium selenide/sulphide.

2. Draw schematic diagram of solar power plant and how electricity is

generated. Schematic diagram of solar power plant:

a. Electricity is generated:

Solar cell operates on principle of Photo-voltaic effect which is

process of generating an emf (DC) when it absorbs sun radiations

OR


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b. Solar cell works in following steps.

Photons in sunlight hit the solar panel and absorbed by

semiconducting material (such as silicon).

Electrons (negatively charged) are knocked loose from their atom

causing an electric potential difference.

Thus converts solar energy into electrical energy without any waste

products.

Or

c. Electricity is generated:

Photovoltaic cell is small semi conductor device which has light

sensitive P-N junction. It made up semi-conducting material and these cells

are light sensitive. The p- Type layer is thick while the N-type layer is thin.

When trivalent impurity is added, P-type semiconductor is obtained. When

sunlight strikes the N-type layer, some of the waves of light energy penetrate

up to the P-type layer. When photons from the sunlight energy are absorbed

in semi conductor, and sunlight energy is greater than energy gap, electron-

hole pairs are formed. Electrons are released from N-type material and holes

are created in P-type material electrical circuit is completed and flow of

current takes place. Photo voltaic cell system converts solar energy directly

into electrical energy without any waste products.

3. Define the following terms related to solar radiation.

Solar constant: The rate at which solar energy arrives at the top of

the atmosphere is called the solar constant.

Beam radiation: Solar radiation that has not been absorbed or

scattered and reaches the earth directly from the sun is called direct

radiation or Beam radiation.


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Diffuse radiation: Is that solar radiation received from the sun to

earth after its direction has been changed by reflection & scattering is

called diffused radiation.

Insolation: The total solar radiation received at any point on the earth

surface is the sum of the direct & diffused radiations is called

Insolation at that point

OR

The Insolation is defined as the total solar radiation energy received

on a horizontal surface of unit area on the ground in unit time.

4. What are the reasons for variation in solar radiation reaching the earth

and that received at the outside of the atmosphere?

Answer:

Following are the reasons for variation in solar radiation:

1. Absorption-

As solar radiation passes through the atmosphere-The short wave ultra-violet

rays are absorbed by the ozone in the atmosphere. And the long wave infra-

red waves are absorbed by carbon di-oxide (CO2) and moisture in the

atmosphere.

2. Scattering-

As solar radiation passes through the atmosphere-The component of the

atmosphere such as water vapor and dust, scatter a portion of solar radiation.

5. Draw the basic photo voltaic system for power generation and state the

function of each block?

Or


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6. Draw the functional block diagram of photo voltaic power generating

system and explain each block in brief.

Answer:

Block diagram for basic photo voltaic system:

Function of each block:

1. Photovoltaic cell panel- Its function is to convert energy of sunlight directly

into DC electricity.

2. Battery charge controller- Its function is to increase life of storage battery.

It protects battery from over charging and it prevents battery from

overcharging.

3. Storage battery- Its function is to store DC electrical energy generated by

PV cell which can be used whenever required. Battery has long life.

Commonly used batteries are-

Lead acid battery

Nickel cadmium battery


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4. Inverter- It converts DC supply into AC supply

5. Step-up transformer- It step up the input voltage to utilization voltage

e.g.230 V.

6. Explain importance of solar power in the energy deficient India.

Since availability of fossil fuels like coal are limited in future so there is more

importance of solar power in the energy deficient because of following advantages

of solar power

1. Renewable energy sources and freely available.

2. No air pollution.

3. Availability of fuel is unlimited & inexhaustible.

4. No fuel storage is required.

5. No fuel transportation cost.

6. No treatment on fuel is required.

7. No waste disposal problem.

8. Generating cost per unit is less and reduces day by day

9. No need to start power plant.

10. It saves the fossil fuel (coal, diesel, oil etc) which are limited

available.

11. Renewable technology are ideally suited to distributed applications (

Decentralized system)

7. Application of Solar Energy:

a. Water Pumping Sets.

b. Weather Monitoring.

c. Railways Signal Equipments.

d. Battery Charging.

e. Street Lighting.

f. Solar water heating.

g. Solar furnace.

h. Solar cooling

i. Solar green house.


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8. Explain working of concentrating type of solar collector.

Answer: Figure concentrating type of solar collector:

Or

All concentrating solar thermal power (STP) technologies rely on four basic

key elements:

Concentrator,

Receiver,

Transport-storage,

Steam generator (Heat exchanger)

Condenser

Steam turbine

Alternator

Working of concentrating type of solar collector:

The concentrator captures and concentrates solar radiation.

This is then delivered to the receiver.

The receiver absorbs the concentrated sunlight,

Transferring its heat energy to a working fluid.(As good as coolant) This

coolant is are-circulated again and again

The transport-storage system passes the fluid from the receiver to the heat

exchanger where steam at high temperature and high pressure generated.


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Or

It consists of cylindrical parabolic concentrator and through reflector has

been made of highly polished aluminum or silver glass or thin film of

aluminized plastic or mirrors on a film base.

And absorber which is well insulated is placed along focus axis.

In this type solar collector, radiation is collected over the area of the

reflecting surface and is concentrated at the focus of the parabola (absorber).

Tracking of collector according to sun direction is necessary for better result.

The tracking is always from south to north direction because there is more

solar energy in this direction than the East-West arrangement.


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Tidal Power Plant

1. State the advantages and Limitations of Tidal power generation.

Answer:

a. Advantages:

It is clean & free from air pollution.

Fuel is freely available.

No transportation cost on fuel & waste disposal problem.

It doesn’t require any combustion of fuel.

It is independent on external fuel supply & fluctuations in existing fuel

rate.

It is renewable energy source.

Tidal energy is in exhaustive.

Long Life.

Cost per unit is less.

It is independent on weather & seasonal condition.

Operation and maintenance cost is less.

No waste of useful land for power plant erecting.

Tides are totally predictable (both in terms of timing & force)

Tides can exchange millions of gallons of water in just minutes.

Dam constructed for tidal power plant may protect coast line again

damage from high storm tides & provide readymade road bridge.

b. Limitations of Tidal Power generation:

High capital cost due to large length & size of dam.

There is limitation on site selection because it requires minimum tidal

range between 5-8 meter


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It provides power only for 10 hours per day.

There is no guaranty that power is generated during peak hours.

Design of dam/ barrage is quit complicated.

Power generation is not in phase with demand.

Changing of tidal range in two weeks period produces changing

power generation.

It affects marine life of fish, animals & environmental at the location /

coastal life.

It may affect/ abstraction to marine traffic.

No firm generating capacity.

Such power plants are located away from load centre so transmission

cost increases.

As water is salted, there is possibility of rusting of equipments.

Time required for completion of project is more due to construction of

dam.

Q.13) Draw the neat sketch of Ocean tidal energy conversion plant. State the

limitations of tidal power Generation.

Answer:

Fig: Two Basine or Linked Basine Scheme


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Fig: Tidal Power Plant or Out Flow Generation

Limitations of Tidal Power generation:

1. High capital cost due to large length & size of dam.

2. There is limitation on site selection because it requires minimum tidal range

between 5-8 meter

3. It provides power only for 10 hours per day.

4. There is no guaranty that power is generated during peak hours.

5. Design of dam/ barrage

6. Power generation is not in phase with demand.

7. Changing of tidal range in two weeks period produces changing power

generation.

8. It affects marine life of fish, animals & environmental at that location/

coastal life.

9. It may affect/ abstraction to marine traffic.

10. No firm generating capacity.

11. Such power plants are located away from load centre so transmission cost

increases.

12. As water is salted, there is possibility of rusting of equipments.

13. Time required for completion of project is more due to construction of dam.


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Biomass and Bio-gas energy

1. What is the meaning of Biomass and Bio-gas energy? Give composition

of Bio-gas and its Calorific value.

Answer:

Bio-mass and Bio-gas:

The power plant in which biomass is used as a fuel to generate electrical is known

as biomass power plant.

Composition of Bio-gas and its calorific Value:

In biogas plant, biogas also called as land fill gas (LFG) is produced. The

composition of biogas is as below

Out of which methane gas is useful to produce electricity by direct combustion

or to run the gas engine in combination with generator. Calorific Value of

Methane:

1. At 40% methane: 3124 Kcal / m3




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2. Write how energy can be stored or generated in each of following: Solar

cell ii) Geothermal energy iii) Hydrogen energy in biomass.

i) Solar cell:

Energy can be stored: Storage Battery is used to store electricity.

OR

Energy can be generated

1. Directly Conversion:

a. By use of P.V Cell (photovoltaic cell)

b. Thermo ionic system conversion

c. Thermoelectric (see beck effect)

2. Indirectly Conversion:

a. Solar thermal power plant

ii) Geothermal energy:

Energy can be stored: The -storage transport system.

Energy can be generated

1. Hydrothermal convective systems:

a) Dry Steam geothermal power Generation:-

b) Wet Steam geothermal power Generation:-

c) Hot water fields

2. Geo-pressure resources:

3. Hot dry rocks (HDR)

4. Magma resources

5. Volcanoes


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iii) Hydrogen energy in biomass:

Gas generated is stored in gas chamber (Dome)

Or

Energy can be generated:

The biomass such as wood, dung and agricultural residues is burnt directly

to obtain energy :

The biomass is converted to fuels such as ethanol and methanol, which can

be used as liquid fuels in engines:

The biomass is subjected to fermentation process to obtain a gaseous fuel

called biomass.


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Interconnected Power System

1. Why the power stations are connected with each other?

Or

2. What is interconnected system? Write any three advantages of this

system?

Answer:

Interconnected system:

Any type of power generating stations e.g. Hydro, thermal, nuclear, gas power

plants are interconnected through transmission line works in combination with

each other to supply the power economically to the consumer, this system is

known as interconnected power system.

Because of the following Reasons or Advantages the power station or plant are

connected it is also called interconnected or grid system:

Reduced Overall installed Capacity: Inter connected power systems

reduce the overall requirement of installed capacity. With interconnection

between power systems, peak demand in an area is meet by importing power

from neighboring area. Thus, it also reduces investment and demand.

Better Utilization Hydro Power: In combined power system, hydro power

can be utilized in more effective way. During rainy season, hydro power

plant can be utilized, while during draught per power plant can be used as

base load plant.

Reliability of Supply: The reliability of steam power plants depends upon

the coal supply and that of hydro power plant depends upon the stream flow.

Due to greater diversity, a combined operation of various types of power

plant is more reliable than individual power plant.

High unit size possible: Generating units of higher unit capacity (200MW,

500MW etc) can be installed and operated economically.


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Improved quality of voltage and frequency: Isolated power systems have

higher frequency fluctuations with change in load. With inter connections,

the system becomes stronger & the effect of load is reduced.

Exchange of peak loads: If the load curve of power station shows a peak

demand that is greater than the rated capacity of the plant, then the excess

load can be shared by other stations connected with it.

Use of older Plants: The interconnected system makes it possible to use

older and less efficient plants to carry peak loads of short durations.

Although such plants may be inadequate when used alone, yet they have

sufficient capacity to carry short peaks up load with other modern plants.

Insure Economical operation: The interconnected system makes the

operation of concerned power station quite economical. It is because sharing

of loads among the stations is arranged in such a way that more efficient

plants work for peak load hours only.

Increases Diversity factor: The maximum demand on the system is

reduced because load curves of different inter-connected stations are

different. So, diversity factor of the system is improved, thereby increasing

the effective capacity of the system.

Increases load factor: The load factor and efficiency of operation are

improved.

Reduces Plant Reserve Capacity: Every power station is required to have a

standby unit for emergencies. However when several power stations are

connected in parallel, the reserve capacity of the system is mush reduced.

This increases efficiency of the system.

Better utilization of natural resources: Due to interconnection, there is

optimum utilization of available natural resources in the country is possible.

3. What is meant by economic loading of interconnected power stations?

How the economic loading is achieved?

4. Explain how to decide the priority of types of plant to share the load.

(Draw Only Figure Given Below)

Answer: Economic Loading means the power plant whose generating cost per unit

is less will share maximum load during whole day. And the power plant whose


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generating cost per unit is more will share minimum load for few hours during a

day (Peak Load) is called economic loading of interconnected power system.

Economic loading is achieved as shown in figure:

Fig: Priority of types of plant to share the load

5. Differentiate between state grid and national grid. What precautions

must be taken in case of national grid?

Answer:


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Precautions must be taken in case of national Grid:

Precaution should be taken that load on grid is adjusted in such way that

avoid cascade tripping during peak load period.

6. Explain how load sharing is achieved between power stations in inter

connected systems.

G1and G2 should be so scheduled as to keep the generation cost per unit

minimum.

Load sharing:

Consider two generating Station G1 and G2 interconnected to each other

through an inter connector (transmission line).

Generator G1 supplies current I1 and G2 supplies current I2 to the load.

If both the generators share the load equally and below its rated capacity,

then there would be no flow of power through transmission line.

But, if any one generator is overloaded, then transfer of power will take

place through transmission line, this is called load sharing.

This is done by connecting regulating equipments at the start of each

transmission line and in inters connector


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Or

Consider two generating station G1 and G2 operating in parallel and

interconnected to each other through transmission line called as interconnected and

these lines both locations of generating stations are at different location. As shown

in figure 1 & 2.

Each generator supplying power to local load and if required power can be

transfer from G1 to G2 or G2 to G1.

If required means in case of peak hours or failure of one of the generating

station or in case of maintenance.

When power transfer exceeds the capacity of single interconnector then in that

case, power is transfer through two interconnector in parallel running along the

same or different routes In this way load sharing between different generating

station is achieve.

7. State what do you mean by base load and peak load power station.

Answer:

Base Load:

The load on power plant (generating station) which is constant throughout

the day is known as Base load plant.

OR

Base Load: - The unvarying load which occurs almost the whole day on the

power plant is called Base load.

Peak Load: - The various peaks demand on the load over and above the

base load of power plant is called peak load.


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Graphical representation of Base load & Peak load also consider without

definition:

8. Compare base load plant with peak load plant on any two points.


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9. Comparism of Various types of Power Stations:

Sr.

No. Particulars

Thermal Power

Station

Nuclear Power

Station

Hydro Power

Station

Diesel Power

Station

1 Site Selection

Near to Load

Center to reduce

cost of coal

transportation

Near to load

centre but

water &

disposal of

waste is easily

available

Ample

quantity of

water required

for generation,

so where

highest rainfall

occurs

Can be installed

anywhere

2 Cleanliness Produces air

pollution

Waste

disposes

causes

problem

Neat & clean Less air pollution

produced

3 Reliability Less Reliable Most Reliable Less

4 Space

required More Less Space More Space Less

5 Application Base load Base load Peak load Peak load

6 Initial cost 10 to 15 lakhs 25 lakhs 15 to 40 lakhs 15 to 25 lakhs

7 Fixed cost per

annum 13% 15% 10% 15%

8 Fuel cost High Low Nil Very high

9 Transportatio

n cost Very high High Nil Very high

10 Maintenance High High Low Low

11 Running cost High Low Much low More

12

Time

required for

work

completion

3 to 4 year Nearly 10 year About 10 year Very short


Mr.N.S.Patil 37

10. Allot the following power stations with reason as base load & peak load

plants.

Answer:

a. Diesel Power Plant: diesel power plant mostly used as a peak-load plant

as the cost of generation is high.

b. Hydro power plant: if source of water is sufficient it will be used as

base load plant, otherwise it will be used as a peak load plant.

c. Nuclear power plant: mostly used as base load plant, as sudden

variation in load are not possible.

d. Thermal power plant: it is used as base-load plant as high efficiency at

high load factor.


Mr.N.S.Patil 38

7. Important Technical Words & its Meaning

Conventional:

Non-conventional:

Sun energy:

Wind energy:

Tidal:

Capital cost:

Reliability:

Limitation:

Sharing:

Reserve Capacity:

Interconnected power system:

National grid:

Grid:

Load dispatch center:

Renewable:

non-conventional energy sources & interconnected power · pdf filemr. nitin s. patil...

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