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Other Sources of Energy

UNIT 9 OTHER SOURCES OF ENERGY

Structure

9.1 Introduction

Objectives

9.2 Need for Non-conventional Energy Sources

9.3 Solar Energy

9.3.1 Agriculture and Horticulture

9.3.2 Solar Thermal

9.4 Wind Power Energy

9.5 Geothermal Energy

9.6 Nuclear Energy

9.7 Tidal Energy

9.8 Summary

9.9 Key Words

9.10 Answers to SAQs

9.1 INTRODUCTION

The rapidly depleting fossil and hydro carbon energy resources and the attendant global

warming issues force energy users and policy planners to look forward to the use of

alternative or non-conventional energy sources to meet the future energy demands. The

non-conventional energy sources like solar energy, wind energy, geothermal energy,

nuclear energy and tidal energy are resources whose use do not impact the environment

adversely. Except nuclear energy all the other above indicated sources are clean, available

in vast quantities and renewable. In view of these advantages it is desirable to utilise these

sources to meet the future and increasing energy demands.

Objectives

After studying this unit, you should be able to

• define non-conventional energy,

• know the various sources of energy, and

• explain about the sources of non-conventional energy sources.

9.2 NEED FOR NON-CONVENTIONAL ENERGY SOURCES

The conventional (primary) energy sources like coal, petroleum based fuels and natural

gas available on earth are finite in quantity and may not last beyond the next century if the

present rate of consumption is maintained. However, the developing nations like China and

India with very low per capita energy consumption and very large populations increase

their energy consumption at a very rapid rate to provide improved lifestyles for their

people. Thus, if the rate of consumption of these primary energy resources increase rapidly

the available fossil and petroleum based fuels may not last even till the middle of the

twenty first century. Hence, world over there is growing awareness that we should

conserve the energy and reduce the energy intensity. Energy intensity is the amount of

energy needed per GDP of a country. Reduced energy intensity means that the process

followed in all production activities and services rendered are energy efficient. However,

with increased demand for energy resources to improve the livelihood of rapidly increasing

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population energy efficiency improvement along is not sufficient. We need to provide

additional energy resources. In this context the non-conventional energy sources which are

mostly renewable in nature not only can meet the needs but are also relatively clean

causing less damage to the environment. Due to these reasons it is imperative that

sufficient attention is focused on these resources to utilise them to the maximum possible

extent.

9.3 SOLAR ENERGY

Solar energy is responsible for the life on earth. All vegetable matter and other living

things on earth are possible only due to solar energy. The amount of solar energy that is

incident on earth is far higher than that needed to meet all our energy needs. However, it

suffers from low intensity, changes with time-necessitating use of larger area devices and

non-availability round the clock to harness the same effectively. In addition, climate

factors like cloud, rain and snow and dust affect the capture and utilisation. Still solar

energy could be effectively captured and utilised both by the thermal route and through

photo voltaic power generation. Eventhough the peak value of the solar radiation received

is close to about 1 kW/m2, this is a very low intensity compared to that obtained with

conventional combustion system and hence any thermal power conversion from solar

energy should have large area collectors and storage with insulation, etc. to effectively

capture solar energy. Since the sunlight is available over a large spectrum (range of

wavelengths) is again poses problems in photovoltaic conversion as there is no single

photovoltaic material which is capable of absorbing all the wavelengths and convert the

same directly to electricity. Considering these limitations the solar energy devices are built

to provide acceptable performance.

An illustrative list of solar applications is listed here. The list is only indicative and not

exhaustive. Agriculture and horticulture, solar thermal (water heating and cooling) and

electrical generation (solar photovoltaic). These applications are briefly discussed in the

following Sub-sections.

9.3.1 Agriculture and Horticulture

In agro processing large quantities of low temperature heat is needed. For example, grain

dying requires heat at less than 100oC and the same can be directly provided by the

sunlight. In rural areas even today people dry their agricultural produces by spreading

them over ground during daytime and after 5-6 hours of exposure to sunlight most of the

moisture present in the grains get removed. However, this approach is not suitable for

continuous processing and for large batches where we need to use solar air dryers. The

solar dryers capture the energy from sunlight and raise the temperature of the air and when

this hot air is blown over the grains the moisture in the wet grains is removed and the grain

becomes dry. The advantage of solar dryers is that the grain is not directly exposed to

atmosphere and even if there is rain the grain will not become wet.

The horticulture produce need cooling to increase the shelf life. The same can be provided

by solar energy operated absorption cooling systems. The heat energy needed to separate

the refrigerant from the mixture in the generator can be supplied by a solar collector-

thermal storage system and thereby the need for heat source is obviated.

9.32 Solar Thermal

Solar thermal systems are generally used to produces hot water and store the same in a

storage device for use over longer periods. The device which collects solar energy and

transfers the same to water to heat it is called as solar collector. The collectors are of

different types with the most popular among them being flat plate collector and

concentrating collector.

The Flat Plate Collector

The flat plate collector is the most popular type of solar energy collector used in

thermal applications. Figure 9.1 shows the cross-sectional view of a solar flat plate

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Other Sources of Energy collector. It consists of an aluminium or steel plate painted on its top surface with

black paint to absorb maximum amount of radiation incident on it. Small diameter

copper tubes are brazed at the bottom of the plate and are in good thermal

conductor with the absorber plate. These tubes are connected to the lower or inlet

header at the bottom and at the top they joint the outlet header. To improve the

efficiency of the collector at the top of the flat plate transparent cover plates are

used. Normally a single cover is used. However, if increased efficiency is desired

multiple (2 or 3) transparent covers are preferred. To reduce the heat loss to the

surrounding, at the bottom of the flat plate insulation is provided. Generally mineral

wool or glass wool insulation to a depth of 100 mm provides excellent insulation.

This ensures that heat is not lost from the plate or from the tubes to the surrounding.

The entire arrangement is housed in a box like structure to give strength and rigidity

to the collector and for easy transportation.

Figure 9.1 : Solar Flat Plate Collector

To improve the collection efficiency the flat plate collector is kept south facing is

countries which are north to the equator at an angular inclination (with referenced to

the horizontal) corresponding to the local latitude.

Water enters the collector through the bottom heater raises slowly to the top header

through the tubes, absorbs the heat from the plate through the walls of the tubes,

becomes hot and gets collected in the top header.

The heat losses from solar flat plate collectors due to different modes are minimised

as follows :

(a) conduction heat loss through the back and sides of the collector but

minimised due to use of good quality insulation.

(b) Convective heat loss caused by air movement. This could be reduced

by employing two or three cover plates. Also providing gaskets to the

cover plates and collector plate to prevent leaking of air ensures that

this loss is minimised.

Solar radiation

Absorber Plate (coated black)

Enclosure Section on xx

Tubings

Insulation

Transparant cover

Top header Hot Water out

X X

Inlet header Water in

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(c) Radiative losses can be minimised by applying selective (black)

coatings to the collector top surface.

Concentrating Collector

Concentrating collector is also known as focusing collector. Following two types of

collectors are popular :

Line Focussing

As shown in Figure 9.2 the line is a collector pipe through which are heat

absorbing fluid flows. Reflecting surface of suitable geometry

(semi-circular reflecting plate with black coated collector pipe at the cenral

axis) focuses the solar radiation along the tube outer surface.

Figure 9.2 : Parabolic Focusssing Collector

Point Focussing

There are many geometric shapes used for this purpose. Popular among them

are : parabolic trough collectors (Figure 9.3), mirror strip reflector, flat plate

collector with adjustable mirrors, compound parabolic concentrator. These

collectors focus the radiation incident on the reflecting surface at the focus

and an absorber (black painted) absorbs the focused high intensity radiation

which results in high temperature. A fluid circulated through the absorber

gets heated to high temperatures and the hot fluid is used for thermal power

applications.

Figure 9.3 : Parabolic through Collector

Solar Water Heating Systems

Hot water

Out glass cover

Parabolic Concentrator

Cold Water in Absorber tube

Overall efficiency of a power generating system

Supporting base

Parabolic Concentrator

Receiver (absorber)

Counter weight

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Other Sources of Energy These are divided into two types namely natural circulation systems and forced or

pumped circulation systems. The components present in a solar heating systems are

flat plate collector, storage tank, circulation system and controls. A typical solar

water heating system is shown in Figure 9.4.

Figure 9.4 : Solar Water Heating System

The storage is a drum of large capacity fully insulated at the top and bottom and

also on the lateral surface. The storage drum has an outlet port provided at the

bottom through which the relatively cooler water comes down and enters the pipe

connecting the storage and the inlet header of the solar collector. Also the drum has

a port at the top just below the free surface of water and an insulated pipe connects

the outlet header of the collector to this port to transport the hot fluid from the

collector to the drum. In addition, ports are provided in the drum at strategic

locations to take out the hot water for use and to supply water from the mains to

maintain constant level in the drum.

No separate circulation system is needed for natural circulation systems. The cold

water in the storage is at a higher density and comes down to the bottom by gravity

and enters the collector, becomes hot and raises through the collector tubes and

through the top header the hot water raises and enters the storage at the top. This is

also known as thermo siphon system.

For forced circulation systems a pump is introduced between the storage bottom

port and the collector bottom header port. This arrangement ensures continuous

circulation of the fluid through the collector even when the sun is covered by cloud

and makes the heat collection efficient.

However, it needs a pump, motor and power supply to ensure circulation.

Controls are needed to maintain level and to provide auxiliary heating in the storage

to provide hot water at desirable temperature for the user.

Heating and Cooling

For these applications the hot water obtained from the solar water heating system is

used. The hot water is taken from the top part of the storage and is conveyed

through insulated pipes to the user. In applications where hot water is used for

indirect heating as in dryers, hot air radiators and in heat exchangers it is passed

through the heating coils, gets cooled and is sent back to the bottom of the storage

using a feed pump. If the heat exchanger transfers this heat to the generator of an

absorption refrigeration system then it helps to produce refrigerant needed for

cooling applications.

Solar Photovoltaic Cell

This is a device which directly converts the incident solar radiation into direct

current (DC) electricity. The photovoltaic panels are made up of semi-conductor

materials like silicon or germanium. In semi-conductors the electron

Hot water Distribution

Auxiliary heater

Hot water tank (storage)

Cold water from main

Solar collector

Insulation

≥ 0.3 m

φ

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conductivity lies between the good conductors and that found in insulators. The

semi-conductors are of the following two types :

(a) Intrinsic semi-conductor which is a pure form of semi-conductor and

has no impurity.

(b) Extrinsic semi-conductor which is formed by adding suitable impurity

to the intrinsic semi-conductor.

In P-type semi-conductor trivalent elements like boron or aluminium are added. In

this type the majority charge carries are holes. The N-type semi-conductors are

created by adding a pentavalent impurity like phosphorous or arsenic and the charge

carriers are electrons.

The normal configuration of a solar cell is a p-n junction semi-conductor. If two

semi-conductor materials are derived from the same element (silicon) by suitable

doping process then it is referred as homo-junction. If a p-n junction is to be formed

two different semi-conductor and a metal (like platinum, gold, silver, etc.) it is

known as schotky junction. Figure 9.5 shows the p-n junction formation and its

working on the photovoltaic effect.

Figure 9.5 : p-n Junction of Solar Cell

Photovoltaic Effect

When solar energy is incident on the panel p-n junction movement of

electrons takes place due to the energy transferred by the photons in the light

to electrons. The movement of electrons (charge carriers) constitute cuttent

flow. Many times the DC current thus generated is stored in a battery. When

conventional AC is needed an inverter is used to convert the DC received

from the cells and the battery. A diode is used to prevent the flow of current

from the battery to the panel during night. If we connect n number of p-v

panels in series the combination increases the voltage n times but the current

remains constant as that obtained in a single panel. On the other hand, if we

connect n p-v panels in series the voltage remains constant as that provided

by a single panel but the current increases n times.

The voltage, current and power delivered by a solar cell are influenced by

(a) the condition of sunlight intensity, wavelength angle of

incidence, etc.

(b) the condition of the junction, its temperature, and

(c) the external resistance.

VI Characteristics of a Solar Cell

The typical test on PV cell is shown in Figure 9.6. When the external

resistance is very high (order of Mega Ohms) the condition is called as open

circuit. The open circuit voltage Voc is the maximum voltage across a PV cell

Sun light

Electron

Load

- VE contact

+ VE contact

Holes

+

Diffused layer

Metal conductor

N region

P region Base material

Current collection grid (Metal fingers)

0.2 m

300 m

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Other Sources of Energy and the open circuit current is zero. If the external voltage Voc is the

maximum gradually and the readings of the terminal voltage and current are

taken we get the V-I characteristics of the PV cell. When the external

resistance is completely shorted the condition is known as short circuit. The

short circuit current Isc is the maximum current across a PV cell. The short

circuit voltage is zero. The VI characteristics of a solar cell is shown in

Figure 9.7.

Figure 9.6 : Testing of Solar PV Cell

Figure 9.7 : VI Characteristics of a Solar Cell

9.4 WIND POWER ENERGY

Wind energy is clean, safe and is a renewable form of energy. For the past many centuries

wind energy has been used for propelling ships and driving wind mills which pump water,

irrigate fields and used for many other applications. The energy conversion principles

associated with wind energy conversion are; converting kinetic energy of wind into

mechanical energy at the shaft. This energy available at the shaft could be either directly

used or fed to an electrical generator and converted into electrical energy and transported

through cables.

The Principle of Wind Energy Conversion

The windmills convert the available kinetic energy of the wind to mechanical

energy. The available power with the wind is a proportional to the square of the

diameter of the turbine and cube of the wind velocity. Hence, site selection plays in

important role. Geographical areas where high annual wind velocities prevail are

ideal locations to install wind turbines.

Components of Wind Energy Conversion Systems

Figure 9.8 shows a typical wind energy conversion system. The wind turbine rotor

(with two, three or four blades) converts the energy of the moving air into rotary

mechanical energy. A mechanical interface consisting of a step up gear and suitable

coupling transmits the rotary mechanical energy to the electrical generator.

Whenever the wind direction change, the machine rotates about the key axis so as to

V/mv

mA/A R

N

P

Isc

PP (peak power point)

Voc

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make the blades face the wind. Thus, the area of the wind swept by the wind rotor is

kept a maximum. In small turbines the yaw action is controlled by the tail vane and

in larger machines a servomechanism operated with input from wind direction

sensor controls the yaw motor to keep the turbine properly oriented. A wind speed

sensor is used to protect the system from extreme conditions brought upon by strong

winds. The type of supporting system (structural tower) and its height is related to

the cost and the type of transmission system used.

Figure 9.8 : Wind Energy Conversion System

Classification of Wind Energy Systems

Broadly wind energy generators are classified as

(a) horizontal axis machines, and

(b) vertical axis machines.

The horizontal axial machines could be build with mono blade, two blades, three

blades and multi blades. In our country the two blade and three blade configurations

are extensively used. Vertical axis machines are built as Savonius rotor type and

Darrieus rotor type. There are some other types of wind machines belonging to the

above classification but are not popular.

Figure 9.9 shows the different types of wind machine rotor configurations.

Advantages of Wind Energy Conversion

(a) important renewable energy source,

(b) energy is freely available,

(c) clean and pollution free,

(d) available in many off and on shore localities,

(e) helps to conserve energy, and

(f) low operating cost.

Limitations of Wind Energy Conversion

Blade Gear box

Generator

Axis of yaw

Nacelle

Yaw Motor

Tower Shaft

Hub

Axis of rotation

Foundation

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Other Sources of Energy (a) low energy density and hence requires huge wind machines which leads to

heavy capital cost,

(b) favourable locations are determined by the geographical topography and

could not be installed in all the places,

(c) due to seasonal factors variation in wind velocity happens and thus, power

produced fluctuates,

(d) huge power demands cannot be met with single machine and hence wind

farms need to be created needing very large areas for limited power output.

Figure 9.9 : Vertical Axis Wind Machines

9.5 GEOMETRICAL ENERGY

Underneath the earth’s hard surface known as crust, is the trapped the molten mass of

earth known as magma which is present at about 3000oC. The curve varies in thickness

ranging from 15 to 150 km and insulates the earth’s outer surface and protects it from the

intense heat of the magma. However, there are certain locations on earth where the

thickness of the crust is small (of the order of few hundred metres) and when the crust is

cracked sub-soil water comes into contact with the hot matter and gets converted into

steam or hot water. There are some locations in Iceland and in Himalayas where such

Savonius rotor Multi-Bladed Savonus

Support mast

Catenary shape

Guy wire

Aerofoil section

Darrius rotor

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natural hot water springs are found. In some other places if we can drill through the crust

over a km or so the hot matter can easily be reached and by pumping water at pressure

over this hot matter it is possible to produce steam which can be collected and brought up

to the earths surface and used in a steam power cycle to produce electricity. The two types

of geo thermal systems which are popular are :

(a) Dry steam system, and

(b) Wet steam system.

These are shown schematically in Figure 9.10.

Figure 9.10 : Geothermal Energy Systems

Dry Steam System

In certain locations dry steam issues out of the earth and it can be directly used in a

conventional steam power plant with suitable accessories. The steam coming out of

the geothermal well is carrying with it liquid water, sand and soil and dissolved

mineral matter from earth. These need to be separated before steam is fed to the

turbine otherwise the life of the turbine blades will be very much reduced due to

erosion. Hence, as shown in the schematic centrifugal separators are used to

separate the solids and the insulated drum is used as the steam generator. The

Centrifugal separator

Steam drum

Slurry

Turbine-generator

GEO

Dry steam

Out

In

Coolant pump

Condensate to chemical recovery or to re-injection well

Dry steam system

Steam/ hot water well

Turbine-Generator

Flash Chamber Hot water at high temp. and pressure Condenser

Out

In Coolant

Brine and condensate to

Re-injection well Geo thermal zone

Wet steam system Steam/hot water well

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Other Sources of Energy exhaust steam from the turbine is condensed in the condenser and the condensate is

either re-injected into the hot geothermal zone or used for chemical recovery.

Wet Steam System

These systems are employed in regions where hot water at high pressure and steam

at a slightly received from the hot zones. This hot water is sent to a flash chamber

which produces steam at slightly lower pressure and temperature. This steam is

used in the steam power cycle. The residual liquid with large amounts of dissolved

solids from the flash chamber mixes with the condensate from the condenser and

this mixture at significant pressure is sent back to the hot zone through re-injection

well.

Advantage of Geothermal Energy

(a) Energy is continuously available and more dependable from than solar or

wind energy.

(b) Capital and running costs are lower compared to nuclear and coal based

thermal power plants.

(c) Less polluting compared to conventional thermal power plants.

Limitations of Geothermal Energy

(a) Dissolved solids in water/steam poses problems of separation.

(b) Complete separation of solids is not possible and hence restrict the life of the

turbine blades.

(c) May cause ground surface or ground water pollution if effluents are not

injected back to the walls.

9.6 NUCLEAR ENERGY

The nuclear energy is obtained by allowing the nuclear fuels to undergo controlled fission

reaction in containers known as rectors. During this fission reaction large quantities of

heat is generated and by using a coolant this heat is removed from the rector. The hot

coolant comes out in the liquid phase only in Pressurised Water Rectors (PWR), enters a

steam generator to produce steam which is used to run the turbine in the steam power

cycle. The coolant after losing the heat in steam generator is again pumped back to the

reactor using a coolant pump. In the case of Boiling Water Reactors (BWR) the coolant

picks up the heat from the reactor, gets heated and undergoes phase change and comes out

of the reactor as super heated vapour and is fed directly to the turbine of the steam power

cycle. The exhaust steam gets condensed in the condenser and the condensate at low

pressure is pumped back to the reactor at high pressure by the feed pump.

A typical nuclear power plant cycle is shown in Figure 9.11. The important components

present and their important functions are as follows :

Nuclear Reactor

The reactor houses the pressure vessel inside which the nuclear fuel core is present.

The core contains passages through which coolant passes and picks up the heat. In

addition the reactor also houses the control rods and their control. The moderator is

present in the reactor either as the coolant or as a separate element of the reactor.

The total fuel elements are surrounded by the reflector. The outer shell of the rector

is covered by thick steel plates. In addition this reactor vessel is enclosed with

sufficient space by the concrete environment shielding of very high thickness.

Nuclear Fuel

This is kept in the form of rods in the reactor. The fuel could be solid or liquid by

the same is kept inside stainless steel tubes known as fuel rods. Once the fuel runs

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out of its life the same is removed from the reactor and fresh fuel rods are inserted

into the reactor core.

Moderator

This is used to reduce the kinetic energy of the fast neutrons produced during fission

reaction. Only slow neutrons can sustain the chain reaction and produces heat. The

moderators used are : graphite, beryllium and heavy water.

Reflector

The reflector reflects the escaping neutrons back into the core. The materials used

as reflector are : water, heavy water and carbon.

Figure 9.11 : Layout of a Nuclear Power Plant

Coolant

Coolant picks up the heat from the core of the reactor and prevents the core from

melting due to enormous heat generated during the nuclear chain reaction. It should

be non-corrosive and non-toxic. Normally water, heavy water and (helium or carbon

dioxide) gases are used as coolants.

Control Rod

The control rods control the rate of chain reactor by absorbing the neutrons

produced during the fission reaction. Materials used for this purpose are cadmium

and boron.

Shielding

Shielding prevents the harmful radiation like α-rays, β-rays and γ-rays from leaving

the reactor zone and entering the surrounding. The inner lining is

50-60 mm thick steel plate and the outer containment shield is thick concrete of up

to 2 m thickness.

9.7 TIDAL ENERGY

Tides are caused by the influence of moon on the waters of ocean and seas. The tide is a

periodic rise and fall in the level of the sea from the mean sea level. The variation in the

level between the high and the low tide may be as high as 10 m at times and thus, provide

sufficient head for exploiting the tidal energy. As shown in Figure 9.12 a dyke or dam is

constructed at locations on the coast line where tidal height variations are significant and a

tidal basin is formed by the dam with the ground. At a height slightly above the observed

Hot coolant

Turbine

Steam generator

Steam

Red pump

Coolant pump

Nuclear reactor

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Other Sources of Energy low tide in the dam a passage is provided connecting the basin with the sea. In this passage

a turbine which can operate efficiently with low heads is provided. Also a passage is made

at slightly lower level than the high tide in the dam. At the time of high tide the water from

the sea enters this passage and fills the basin. During the time of low tides the water from

the basin is allowed to pass through the turbine which is connected to a generator and

power is produced.

Advantages of Tidal Power

(a) Free from pollution as no fuel is used.

(b) Compared to hydro power lack of rain will not affect the tidal power plant.

(c) Basin formed could be used for viniculture and for recreational uses.

Limitations of Tidal Power

(a) Tidal plans could be built at only select few naturally favourable sites in the

bay.

(b) Supply of power is not continuous as it depends up on timing of tides.

(c) Because of low heads the quantity of power generation is restricted.

Figure 9.12 : Tidal Power Plant

SAQ 1

(a) What are the limitations of conventional energy sources?

(b) List the advantages of non-conventional energy sources.

(c) Give some applications of solar energy.

(d) Describe briefly the construction of solar flat plate collector.

SAQ 2

(a) How are solar (thermal) hot water systems built? Explain giving a sketch.

(b) What are the different types of solar water heating systems?

(c) List the types of concentrating type collectors in use. Also give their sketches.

(d) What is the principle of solar photovoltaic conversion?

Dam

High tide

Tidal basin

Dam

Tidal basin

Low side T. G T. G

T.G. turbine generator

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SAQ 3

(a) Describe the construction of solar cell.

(b) List the different types of wind energy converters.

(c) What are the components present in vertical axis wind mill? Describe using a

neat sketch.

(d) Explain with sketch constructional details and working of a geothermal power

plant.

SAQ 4

(a) How does a nuclear power plant convert the nuclear energy in to electricity?

(b) With a schematic explain the constructional features of a nuclear power

plant.

(c) List the functions served by following in a nuclear reactor : shielding,

moderator and control rods.

(d) Draw neat sketch of a tidal power plant and explain the construction and

working.

(e) List the advantages and limitations of a tidal power plant.

9.8 SUMMARY

In this unit, we have studied more about the non-conventional sources of energy.

Non-conventional energy we clear green energy sources, which are easily available sources

of energy. Various sources of non-conventional energy are (wind, tital, solar) discussed in

this unit. Mostly applications of the non-conventional energy sources have been discussed

in this unit.

9.9 KEY WORDS

Solar Energy : The energy available through sunrays is known as

solar energy.

Wind Energy : It is clean, safe and is a renewable form of energy.

Nuclear Energy : It is obtained by allowing the nuclear fuels to

undergo controlled fission in containers or reactors.

9.10 ANSWERS TO SAQs

Refer the preceding text for all the Answers to SAQs.

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FURTHER READING

P. K. Nag (1988), Engineering Thermodynamics, Tata McGraw-Hill Publishing

Company Limited.

Y. V. C. Rao (1993), An Introduction to Thermodynamics, Wiley Eastern Limited,

New Delhi.

R. Natarajan (1984), Thermodynamics Analysis of Energy Systems and Processes.

J. Holman (1974), Thermodynamics, McGraw-Hill Publishing Company Limited.

D. B. Spalding and E. H. Cole (1975), Engineering Thermodynamics, Edward Arnold.

R. John Howell and O. Richard Buckius (1987), Fundamentals of Engineering

Thermodynamics, McGraw-Hill Book Company.

G. J. Van Wylen and R. E. Sonntage (1965), Fundamentals of Classical

Thermodynamics, John Wiley and Sons.

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BASICS OF THERMAL ENGINEERING

This course, Basics of Thermal Engineering, comprises of nine units.

Unit 1 Fundamental Concepts and Definitions deals with nature and scope of

thermodynamics, laws of thermodynamics and classification of properties. In this unit, we

discus about the SI system of units and definitions. Thermodynamics is a branch of

physical science related to the laws of nature pertaining to energy, work, heat and all the

properties associated with them.

Unit 2 Laws of Thermodynamics, describe the first and second laws of thermodynamics. It

also explains the concepts of internal energy, reversible engine, Carnot cycle, entropy, etc.

Unit 3 Formation of Steam and its Properties, elaborates on various phases of steam

formation and its applications.

Unit 4 Steam Generators deals with boilers and their classification, construction features,

boiler mountings, accessories, fuels for boilers and performance of boilers.

Unit 5 Steam Prime Movers explains the concept of Rankine cycle, effects of pressure and

temperature on Rankine cycle, steam turbines and its efficiency.

Unit 6 Steam Condensers describes condenser types, condenser operation, types of cooling

towers, ponds and sources of air in the condensers.

Unit 7 Steam Power Plants, deals with layout of steam power plant and its relates circuits.

Unit 8 Heat Transfer explains the various modes of heat transfer and its applications. It

also defines and explains concept of conduction, convection and radiation.

Unit 9 Other Sources of Energy explains the importance of non-conventional energy

sources. It also elaborates on the systems of solar energy, wind energy, geothermal energy,

nuclear energy, tidal energy and its applications.

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