Short term course Proceedings on Renewable Energy
2008
PROCEEDING OF A SHORT -TERM COURSE ON
RENEWABLE ENERGY
September-November 2008
Edited by
Dr. Mukesh Kumar
Conduct jointly by
Swami Shraddhanand College ,
University of Delhi , Alipur, Delhi110036.
&
Mahatma Gandhi Institute of Integrated Rural Energy
Planning Development ,
Govt. of NCT, New Delhi.
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Short term course Proceedings on Renewable Energy
2008
Short Term Course
RENEWABLE ENERGY
Proceeding
________________________
September - November2008
________________________
Edited by
MUKESH KUMAR
COURSE CONVENER (SSNC)
FACULTY, PHYSICS DEPARTMENT
SWAMI SHRADDHANAND COLLEEGE
UNIVERSITY OF DELHI
____________________________________________________
Note : Proceeding is totally based on submitted project report & delivered talks
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Foreword from the organizer : Convener(SSNC)
Preface
The short term course on Renewable Energy was jointly established by the Swami
Shraddhanand College, University of Delhi (SSNC) and the Mahatma Gandhi Institute of
Integrated Rural Energy Planning Development , Govt. of NCT, New Delhi, (MGIREPD) to
assess available information on the science, impacts and the economics of energy resources
and of mitigation options to address it. A thriving renewable energy industry is a critical
solution to problems such as high energy prices and climate change.
We extend our sincere gratitude to the MGIREPD for hosting this workshop. We also thank
Dr. Ravinder Palakurthy the course coordinator form MGIREPD, who gave invaluable
advice on programme, participants and papers.
We would like to thank all participants, who contributed to a very constructive and fruitful
meeting, where exchanging views and opinions on the issues surrounding the use of
renewable energy sources lead to more clarity of the issues involved and the current status
of scientific research. We hope that this short term course will be a major step in an
increased understanding of the applicability of renewable energy sources for the mitigation
of climate change.
Dr. Mukesh Kumar
Coordinator
Short term course on Renewable energy
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Table of Contents
Preface
Geography and Renewable Energy - Prof. Joan Schreijaeg-Gilmour
Sydney (Australia)
Renewable Energy & Applications - Dr. Jai Prakash
BCAS, DU
Geothermal Energy – Energy from the Earth’s Core
11
Study of Bio-Energy
13
Resources
3
5
9
Tidal Energy
15
Solar Water Heater
18
Photovoltaic Cell
20
Introduction to Wind Energy
22
Introduction to Solar Equipments
25
Solar Thermal Energy
27
Appendix
Program Copy
29
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Geography and Renewable Energy
Geography as defined by the oxford dictionary is "the study of the physical features of the
earth And of human activity as it relates to these" Humans have always inhabited two
worlds. One is the natural world of plants, animals, Soils, air and water that preceded us by
Billions of year, of which we are a part. The other is the world of social institutions And
material object that we created for Ourselves using science, technology and Political
organizations. Both worlds are Essential to our lives but integrating them Successfully is an
art.
Where earlier people had limited ability to after their surrounding, we now have power to
extract and consume resources, produce waste and modify our world in ways that threaten
both our continued existence and that of many organisms with whom we share this planet.
To ensure a sustainable future for ourselves and future generations, we need to understand
something about how our world works, what we are doing to it and what we can do to
protect and improve it.
For an increasing number of environmental issues, the difficulty is not in identifying
remedies. Remedies are now well understood. The problem is to make them socially,
economically and politically acceptable. Foresters for example for example, know how to
plant trees, but do not know how. To establish conditions under which villagers in
developing countries can manage plantations for themselves.
Engineers know how to control pollution but not how to persuade factories to install the
necessary equipment to lessen the pollution. City planners know how city buildings and
housing should be built and how to design safe water drinking system but not how to make
them affordable for the poorest members of society. The solutions to these problems
increasingly involve human social system as well as natural science.
Geography to-day is no longer looking at the world in its original explorers were able to
discover the different countries revealing their landmark features together with the flora
and fauna and the nature of the people who dwelt in far off lands. While there are many
things to appreciate and celebrate about the world in which we live, many pressing
environmental problems envy out for our attention. human p[populations have grown at
alarming rates within the last 100 years nearly 6 billion people now occupy the earth and
we are adding round 90 million more each . demographers warn that the numbers of
humans 100 years from now could be four or five times our present populations and if we
do not act quickly to bring birthrates into balance with death rates , we can ask ourselves
if there will be sufficient resources to support 25 billon people on a sustainable basis and
this question is one of the most pressing issues in the world to-day. how we might stabilize
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Short term course Proceedings on Renewable Energy
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population and what level of resource consumption we and future generations can afford
are equally difficult parts of this challenging equation.
Food shortage and famines are already too familiar in many places and may increase in
frequency and severity if population growth, soil erosion and nutrition depletion continue
at the same rate in the future as they have in the past. There quarters of the world's poorest
nations are in Africa. Millions of people lack adequate food, housing, medical care, clean
water and safety. the human suffering engendered by this poverty is tragic , we are coming
to realize that food security has quite often more do with poverty and equitable. Many
countries already have serious water shortages and more than 1 billion people lack access
to clean water and sanitation.
How we obtain and use energy is likely to play a crucial role in our
environmental future. Fossil fuels (oil, coal and natural gas) presently supply about 80% of
the energy used in industrialized countries. supplies of these fuels are diminishing at an
alarming rate and problems associated with their acquisition and use-air and water
pollution , mining damage , shipping accidents and political insecurity -may limit where
and how we use our remaining reserves. Cleaner, renewable energy resources-solar power,
wind and geothermal energy-together with conservation, may replace enviournmentally
destructive energy sources if we invest in appropriate technology in the next few years.
Acids formed in the air as a result of fossil fuel combustion have already caused extensive
damage to buildings and sensitive ecosystems in many places. Two such examples which
come to mind are the pitted marble domes of the Taj Mahal at Agra, India and the other is a
decimated section of the Black Forest in the southern most part of what used to be called
Western Germany.
Acres of tree lost their needles due to the acid rain which came from the belching
uncontrolled smoke from the factories in what used to be called Eastern Germany.
We realize now in 2008 that our present levels of coal and oil consumption cannot
continue. We are being forced to find alternative forms of energy and find the quickly
because we have seen what damage has been done up until now from the extreme air
pollution problems caused by industry, the water pollution problems in the rivers, lakes
and cleans of the world caused by negligent chemical factories and the degradation of
forest on land in all parts of the world for urbanization and wrong farming methods leading
to soil deprivation and erosion. Climate change has emerged as an environmental and
development issue of global concern. The Clean Development Mechanism (CDM) under the
United Nation Framework Convention on Climate Change (UNFCCC) has been conceived as
a global co-operative instrument for cost effective Greenhouse Gas Mitigation and
promotion of sustainable development.
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In India, there are Wind Energy Projects which have been registered under the Clean
Development Mechanism by the United Nation Framework Convention on Climate Change.
These wind project will deliver Green Power and reduce emissions of Greenhouse Gases
this make India eligible to earn certified emission reduction credits (c e or’s) which wail
provide an additional revenue source to our wind power division. Economical goals in an
ecologically responsible manner.
We have to think of the kind of energy that India needs. It has to be affordable and
accessible, otherwise sustainability is not possible. We have to think of a programmed
approach when looking at habits, thinking globally but acting locally . Low cost have to be
created for the local community and only local answer to local problems can give local
answer to sustainability. Future generations must not have to face the problems that we
are facing. India needs to grow at 9%or 10% in order to buy the new technologies. The
Delhi metro has been conceived with concerns for the environment .it is partly owned by
the state government and partly owned by the federal government. The amount of
passengers on the metro carries the equivalent of 6 lanes of buses and it is a great
successful project.
The way in which global energy needs are met will determine whether climate change will
remain manageable and whether emissions will go down by the required 50% by2050
instead of up by 50%. Environmentally sound technologies(EST'S) are essential to
addressing climate change. Technology has thus become one of the central elements which
will move the climate change process forward And it needs to be boosted urgently. A
Copenhagen agreement in 2009 needs to contain effective language that will unleash the
full potential of technology. Views opposing intellectual property Right for technologies
maintain that I P R's make it more difficult to secure access to a global public good and that
intellectual Property Right prevent developing countries from accessing affordable and
adequate technologies. Many existing friendly technologies are not protected by patent and
therefore e I P R's may not be relevant. Patent do not target the basic technology but rather
specific improvement to these technologies. Countries that take early action in developing
green technology will have a competitive advantage as this boom industry grows in the
future. A review has found that climate change will be more divesting than both of the
world wars and the Great Depression of 1929. Ignoring it could reduce Global G D P (Gross
National Product) by as much as 20%. Renewable energy programmers in Germany and
Spain are just ten year old but have already created hundreds of thousands of jobs.
Germany is known for car giants like B M W (Bayerische Motor WERKE), Daimler bebz and
v w (bayerische motor werke),
Daimler Benz and jobs in the field of environmental technologies than in its entire car
industry.
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Energy is the ability to dope work such as moving matter over a distance or causing a heat
transfer between two objects at different temperatures. The energy contained in moving
objects is called kinetic energy. A rock rolling down a hill, the wind blowing through the
trees, water flowing over a dam or electrons speeding around the nucleus of an atom are all
examples of kinetic energy. Potential energy is the stored energy that is latent but available
for use. A rock poised at the top of a hill and water stored behind a dam is examples of
potential energy. Chemical energy stored in the food you eat and the fuel you put in your
car are also examples of potential energy that can be used to do useful work. Solar energy is
useful to life. Several sustainable energy sources could reduce or eliminate our dependence
on Fossil fuel and nuclear energy. Active solar, air and water heating for example require
less material and function more quickly than passive solar collection. Wind is now the
cheapest form of new energy in many places. One of the most promising technologies is
direct electricity generated by photovoltaic cells. Since solar energy is available
everywhere, photovoltaic collectors could provide clean, inexpensive, non-polluting
renewable energy independent of central power grids or fuel supply systems.
One of the most difficult problems associated with nuclear power is the disposal of waste
produced during mining, fuel production and reactor operation.70% of the nuclear plants
in the united states of America and in the world are pressurized water reactors (PWR).
Water is circulated through the core absorbing heat as it cools the fuel rods. This water is
heated to 3170C and reaches a pressure of 2.235psi. It is then pumped to a steam generator
where it heats a secondary water cooling loop. All is contained in a thick walled concrete
and steel containment building that prevents radiation from escaping.
A simpler but more dangerous reactor design is the boiling water reactor (BWR) where
water from the reactor core boils to make steam which directly drives the turbine
generators. This means that highly radioactive water and steam leave the containment
structure. Controlling leaks is difficult and the chances of releasing radiation in an accident
are very high.
The Chernobyl nuclear power plant disaster of 26 April, 1986 in Russia was a lesson to the
world in the dangers of using atomic energy. Many scientists say that we should learn from
this tragedy and abandon this dangerous technology.
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History of Energy Development
RENEWABLE ENERGIES
AND APPLICATIONS
106 years
ago
105 years ago
104 years ago
103 years ago
2000 B.C.
100 B.C.
1200 B.C.
1750
1850
1880
1882
1892
1905
1954
1968
1970s
2020(?)
Dr. Jai Prakash
Principal
Bhaskaracharya College of Applied Sciences
University of Delhi
Human Muscle
Fire (wood)
Horse, oxen
Wind (used for transportation)
Coal: first time used by Chinese
Waterwheel (stored solar)
Windmill (grinding, water pumping, etc.)
Steam engine (trains, boats)
First petroleum from “oil wells”
Internal combustion engine
First hydro electric power station
First electricity producing wind machine
First geothermal electric power station
First nuclear electric power station
First tidal electric power station
Initial commercial use of photovoltaic cells
Net energy produced by a fusion device
Flow diagram for
energy resources development and use
Solar Photovoltaics
E
E
E
Transportation
Conversion of
Primary energy
to usable form
Distribution
Waste
Waste
Waste
E
Raw material
extraction
Waste
Wind Power
Tidal Power
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E
Use by
consumer
Waste
Decommissioning
Waste
Short term course Proceedings on Renewable Energy
SOLAR PHOTOVOLTAICS
ENERGY SOURCES

R E N E W A B LE
S o la r
T h e rm a l
W in d
B io m a s s
O ce a n
H y d ro P o w e r
H y d ro g e n

O ce a n
T h e rm a l
P h o to v o lta ic
2008

W a ve
T id a l

S a lin ity
Generates electricity directly from sunlight by
using solar cells.
Today, India is one of the largest
manufacturers in the world of solar photovoltaic
panels based on crystalline silicon solar cells.
Large number of industries are engaged in the
production of solar cells and modules.
Companies are designing and supplying solar
PV systems.
C u rre n t
Geothermal power
Hydel Power
Nuclear power
BIO-GAS
Potential
: 12 million family size plants
Strategy
: Subsidy with institutional financing
Achievement
: 2.59 million plants
Energy equivalent
: 100 MW
Fuelwood saved
: 75 million tonnes per annum
Number of trees equivalent
: 300 million per annum
NATIONAL PROGRAMME
•
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National Project on Biogas Development (NPBD)
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Short term course Proceedings on Renewable Energy
Geothermal Energy -Energy from the Earth's Core
The word geothermal comes from the Greek words geo (earth) and thermal (heat). So,
geothermal energy is heat from within the earth. Geothermal energy is generated in the earth's
core, about 4,000 miles below the surface. Deep underground, the rocks and water absorb the
heat from this magma. The temperature of the rocks and water get hotter and hotter as you go
deeper underground . This heat can be used as a form of energy resource .
Available forms of Geothermal Energy ?



Volcanoes and fumaroles
Hot springs
Geysers.
Is Geothermal Energy is Renewable Energy ?
Geothermal energy is a renewable energy source because the water is replenished by rainfall and
the heat is continuously produced inside the earth.
Where is Geothermal Energy found ?
Most geothermal reservoirs are deep underground with no
visible clues showing above ground. The most active geothermal
resources are usually found along major plate boundaries where
earthquakes and volcanoes are concentrated. Most of the
geothermal activity in the world occurs in an area called the
Ring of Fire. This area rims the Pacific Ocean.
Uses : Some applications of geothermal energy use the earth's
temperatures near the surface, while others require drilling miles into the earth. The three main
uses of geothermal energy are:

Direct Use : The direct use of hot water as an energy source has been happening since
ancient times. The Romans, Chinese, and Native Americans used hot mineral springs for
bathing, cooking and heating. Today, many hot springs are still used for bathing, and
many people believe the hot, mineral-rich waters have natural healing powers. After
bathing, the most common direct use of geothermal energy is for heating buildings
through district heating systems. Hot water near the earth's surface can be piped directly
into
buildings
and
industries
for
heat.
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

2008
Electricity generation : The hot water produced inside the earth is use to generate
electricity.
Geothermal heat pumps : The use of hot water to control building temperatures above
ground.
Geothermal Power Plants :
Geothermal power plants use hydrothermal resources which have
two common ingredients: water (hydro) and heat (thermal). Geothermal plants require high
temperature (300 to 700 degrees Fahrenheit) hydrothermal resources that may come from either dry
steam wells or hot water wells. We can use these resources by drilling wells into the earth and piping
the steam or hot water to the surface. Geothermal wells are one to two miles deep.
There are three basic types of geothermal power plants:



Dry steam plants - use steam piped directly from a geothermal reservoir to turn the
generator turbines. The first geothermal power plant was built in 1904 in Tuscany, Italy
at a place where natural steam was erupting from the earth.
Flash steam plants - take high-pressure hot water from deep inside the earth and
convert it to steam to drive the generator turbines. When the steam cools, it condenses
to water and is injected back into the ground to be used over and over again. Most
geothermal power plants are flash plants.
Binary power plants - transfer the heat from geothermal hot water to another liquid.
The heat causes the second liquid to turn to steam which is used to drive a generator
turbine.
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STUDY OF BIOENERGY RESOURCES
Bio-Energy include wood, crops like corn and soy beans and waste from consumer, municipal, industrial,
and agricultural processes , that can be burned to produce energy.
How Bioenergy is a renewable resource : Because it uses rapidly renewable materials like
wood and crops as fuel as opposed to fuels like coal, oil, and natural gas that take thousands of years to
regenerate. Some forms of bioenergy rely on waste from consumers, construction, landfills, and other
human sources. These forms are considered renewable because they are produced on a continual basis,
and using them as fuel is an effective way to put them to use.
Bioenergy Resources :
Bioenergy technology converts the chemical energy stored in organic
matter into heat and power. It encompasses a broad range of solid, gaseous, and liquid fuels that result
from living organisms or from the wastes and by-products of human activities. The sun is the root source
of all biofuels, making the Earth inhabitable for life itself and fueling the photosynthetic processes that
transform seeds into trees and plants.
Organic matter can be used directly or indirectly as a fuel:



Primary bioenergy sources include harvested trees and non-woody crops grown and processed
specifically for energy production.
Secondary bioenergy sources include wood residue such as trimmings and woodchips
generated by logging and other industries, pulping (or black) liquor from pulp and paper
facilities, and urban wood waste such as pallets and construction debris. They also include
municipal solid waste (MSW), animal waste, agricultural residue, and food processing waste.
Derivative bioenergy sources include landfill gas (LFG) resulting from the anaerobic
decomposition of organic materials at MSW disposal sites, as well as digester gas resulting from
similar processes at wastewater treatment plants and livestock operations. They also include
gaseous and liquid biofuels produced by living organisms or derived from organic matter, such
as methane, ethanol, biodiesel, and hydrogen.
Uses of Bioenergy :



Some of the uses of bioenergy include:
Electricity Production: Wood, construction waste, landfill gas, and liquid biofuels like biodiesel
and bio-oil can be used to produce energy that can be converted into electricity.
Heat: Essentially all bioenergy fuels can be used to directly produce heat.
Transportation: Liquid biofuels like ethanol, biodiesel, and bio-oil can be used to power cars and
other transportation.
Bioenergy Technologies : Many different approaches exist for converting biomass into heat and
power.
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
Cofiring : It represents an option for producing some green electricity at power plants designed
to operate on coal or other fuels. Processed solid biomass is added to the boiler along with the
fossil fuel to help reduce reliance on finite resources and decrease overall emissions of
pollutants and greenhouse gases.

Landfill and Digester Gases : Landfill gas is created when food, wood, and other organic waste
in a landfill decomposes under anaerobic – or oxygen free – conditions. Because landfill gas is
about 50 percent methane, it can be used as a source of energy similar to natural gas (which is
about 90% methane). Since landfill gas is generated continuously, it provides a reliable fuel for a
range of energy applications, including heating and electric power generation. Landfill gas and
digester gas are typically burned in conventional internal combustion engines or combustion
turbines after being collected and treated. These biofuels arise when bacteria that thrive in
oxygen-poor environments feed on organic materials buried in landfills or found in human and
animal wastes. Landfill gas is collected by drilling wells or installing pipes in horizontal trenches
within a landfill, while digester gas can be extracted directly from enclosed digester systems at
wastewater treatment facilities and agricultural operations.
Biomass Gasification : In biogasification systems, solid biomass is first broken down from
complex hydrocarbons into simpler gaseous molecules. This is accomplished by heating it to a
very high temperature or by "feeding" it to anaerobic bacteria in a process analogous to that
occurring at landfills and in digesters. The by-product mixture includes desired constituentshydrogen and carbon monoxide-as well as a variety of contaminants. The gaseous fuel is then
burned in conventional boilers or gas turbines, either directly or after cleanup, to generate
useful energy.
Liquid Pyrolysis :Liquid pyrolysis technology is similar in concept. Solid biomass is heated rapidly
in a high-temperature, oxygen-free environment, converting it into a liquid fuel (bio-oil) as well
as other products. The bio-oil can then be converted into useful energy in conventional
combustion systems.
Biodiesel Cogeneration: An emerging use of bioenergy is the use of bio-diesel, a liquid bio-based
fuel, to power a combined heat and power generation system. These systems produce both
power and heat and are typically run on a liquid or gas fuel like oil or natural gas.



Advantages : The competitiveness of all bioenergy technologies depends strongly on the cost and the
characteristics of the fuel source.


Biodiesel cogeneration is an extremely cost-effective form of clean energy, combining the
practical efficiencies of cogeneration technologies like diesel generators with renewable
biomass fuels.
An additional benefit of bioenergy is its availability.
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TIDAL ENERGY
Tidal energy is the utilization of the sun and moon's gravitational forces - as tides are formed by the
gravitational pull of the sun and moon on the oceans of the rotating earth. Tides can be found with
varying degrees of strength on any coastline, and sometimes even at sea, although these are better
known as currents. A flood tide is one that is coming in or rising and an ebb tide is one that is going out.
TIDAL ENERGY AS A SOURCE OF RENEWABLE ENERGY
Tidal energy is classified as a renewable energy source, because tides are caused by the orbital
mechanics of the solar system and are considered inexhaustible within a human timeframe. The root
source of the energy comes from the slow deceleration of the Earth's rotation. The Moon gains energy
from this interaction and is slowly receding from the Earth. Tidal energy has great potential for future
energy and electricity generation because of the total amount of energy contained in this rotation.
Variation of tides over a day :
Tidal energy is generated by the relative motion of the
Earth, Sun and the Moon, which interact via
gravitational forces . Periodic changes of water levels,
and associated tidal currents, are due to the gravitational
attraction by the Sun and Moon. The magnitude of the
tide at a location is the result of the changing positions of
the Moon and Sun relative to the Earth, the effects of
Earth rotation, and the local shape of the sea floor and
coastlines. A tidal energy generator uses this
phenomenon to generate energy. The stronger the tide,
either in water level height or tidal current velocities, the
greater the potential for tidal energy generation.
Tidal movement causes a continual loss of mechanical
energy in the Earth–Moon system due to pumping of
water through the natural restrictions around coastlines,
and due to viscous dissipation at the seabed and in
turbulence. This loss of energy has caused the rotation of
the Earth to slow in the 4.5 billion years since formation.
During the last 620 million years the period of rotation has increased from 21.9 hours to the 24 hours.
We see now; in this period the Earth has lost 17% of its rotational energy.
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TYPE OF TIDAL ENERGY :
1. Tidal steam energy that is derived from kinetic energy that harness the currents between ebbing and
surging tides .Tidal stream systems make use of the kinetic energy of moving water to power turbines, in
a similar way to windmills that use moving air. . This method - generating energy from tidal currents - is
considered far less costly and much more feasible today than building expensive ocean-based dams or
barrages, and many coastal sites worldwide are being examined for their suitability to produce tidal
(current) energy.
2. Potential energy from the difference in height (or head) between high and low tides. Barrages make
use of the potential energy in the difference in height (or head) between high and low tides. Barrages
suffer from very high civil infrastructure costs, a worldwide shortage of viable sites, and environmental
issues.
METHODS OF CONVERTING TIDAL ENERGY INTO ELECTRICITY
1. Tidal steam systems -
The tidal steam energy is derived from the kinetic
energy of the moving flows using devices that superficially resemble wind turbines,
and as such differs from tidal barrages which rely on providing a head of water
behind a structure for energy extraction. Tidal stream energy converters extract and
convert the mechanical energy in the current into electricity.
The main components of a tidal stream energy converter are:




The prime mover which extracts the energy from the flow - a rotor of some
sort;
The foundation which holds the prime mover in the flow and reacts the loads
to the seabed;
The power train (i.e. gearbox & generator), and:
The power take-off system (power electrical and control system, and
submarine cable to onshore grid connection point).
Advantages :
The key advantages of tidal stream energy over other renewable
are:





High energy intensity ⇒smaller cheaper rotors for a given power
Predictable energy capture ⇒less project risk
Energy to a timetable ⇒greater revenue per MWh generated
Low environmental impact ⇒low development overheads
Simple decommissioning ⇒low back-end risk and cost
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2. Barrage method -
2008
The basic elements of a barrage are caissons,
embankments, sluices, turbines, and ship locks. Sluices, turbines, and
ship locks are housed in caissons (very large concrete blocks).
Embankments seal a basin where it is not sealed by caissons.The sluice
gates applicable to tidal power are the flap gate, vertical rising gate,
radial gate, and rising sector.
The basin is filled through the sluices until high tide. Then the sluice gates
are closed. (At this stage there may be "Pumping" to raise the level
further). The turbine gates are kept closed until the sea level falls to create sufficient head across the
barrage, and then are opened so that the turbines generate until the head is again low. Then the sluices
are opened, turbines disconnected and the basin is filled again. The cycle repeats itself.
Energy calculations
The potential energy contained in a volume of water is given by
where h is the vertical tidal range, A is the horizontal area of the barrage basin, ρ is the density of water
and g is the acceleration due to the Earth’s gravity .
ADVANTAGES OF TIDAL ENERGY
The most important advantage of tidal energy is its economical benefits, as tidal energy does not
require any fuel. Tides rise and fall every day in a very consistent pattern. The economic life of a
tidal plant is very high. A plant is expected to be in production for 75 to 100 years, in
comparison with the 35 years of a conventional fossil fuel plant. Besides the economical factors,
tidal energy is clean and renewable, unlike fossil fuels. Tidal energy offers a lot of potential to be
a substitute for hydrocarbon and fossil fuels. A very important feature of tidal energy is that it is
non-polluting and a barrage can also safeguard coastlines from storms
DISADVANTAGES OF TIDAL ENERGY
Tidal energy plants do not produce energy 24 hours a day. A conventional design, in any mode of
operation, would produce energy for 6 to 12 hours in every 24 and will not produce energy at other
times. As the tidal cycle is based on the period of revolution of the Moon (24.8 hours) and the demand
for electricity is based on the period of revolution of the Sun (24 hours), the energy production cycle
will not always be in phase with the demand cycle.
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SOLAR WATER HEATER
Solar energy can be captured to heat water or air. The hot water created by a solar system can be
used for domestic hot water or space heating . The fundamental requirement for a solar system is to
have a sunny location where the solar collectors can be located .
Type of Solar Heating :
 Active Solar Domestic Water Heating : The active water systems that can be used to
heat domestic hot water are the same as the ones that provide space heat. There are
five major components in active solar water heating systems:
 Collector(s) to capture solar energy.
 Circulation system to move a fluid between the collectors to a storage tank
 Storage tank
 Backup heating system
 Control system to regulate the overall system operation
A heat exchanger is used to transfer the heat from the fluids circulating through the collectors to
the water used in the home. The fluids that are used in the collectors can be water, oil, an antifreeze
solution, or refrigerant.

Passive Solar Water Heating : A passive
solar water heating system uses natural
convection or household water pressure to
circulate water through a solar collector to a
storage tank or to the point of use. passive
system are generally less efficient than active
systems, the passive approach is simple and
economical. There are two types of passive
water heaters : Batch and Thermosyphon
Batch system
It consists of one or more metal water tanks painted
with
a
heat
absorbing
black
coating
and
placed in
an
insulating
box
or
container
with a glass or plastic cover that admits sunlight to strike
the tank directly. The batch system's storage tank is the
collector as well. These systems will use the existing
house pressure to move water through the system. Each
time a hot water tap is opened, heated water from the
batch system tank is removed and replaced by incoming
cold water.
Thermosyphon System
The thermosyphon system uses a flat plate collector and a separate storage
tank that must be located higher than the collector. The storage tank,
located above the collector receives heated water coming from the top of
the collector into the top of the storage tank. Colder water from the bottom
of
the
storage tank
will
be
drawn into
the lower
entry of the
solar
collector to
replace the
heated
water that
was
thermosyphoned upward. The storage tank may or may not use a heat
exchanger. The thermosyphon system is more costly and complex than the
batch system
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PHOTOVOLTAIC CELL
The "photovoltaic effect" is the basic physical process through which a photovoltaic ( PV ) cell
converts sunlight into electricity.
HOW PV cell Works : Sunlight is composed of photons, or particles of solar energy. These photons
contain various amounts of energy corresponding to the different wavelengths of the solar spectrum.
When photons strike a PV cell, they may be reflected or absorbed, or they may pass right through. Only
the absorbed photons generate electricity. When this happens, the energy of the photon is transferred
to an electron in an atom
of the cell (which is
actually a semiconductor).
With its newfound energy,
the electron is able to
escape from its normal
position associated with
that atom to become part
of the current in an
electrical circuit. By leaving
this position, the electron
causes a "hole" to form.
To induce the electric field
within a PV cell, two separate semiconductors are sandwiched together. The "p" and "n" types of
semiconductors correspond to "positive" and "negative" because of their abundance of holes or
electrons. Sandwiching these together creates a p/n junction at their interface, thereby creating an
electric field . It's this field that causes the electrons and holes to jump from the semiconductor out
toward the surface and make them available for the electrical
circuit.
The most common way of making p-type or n-type silicon
material is to add an element that has an extra electron or is
lacking an electron through the a process called "doping.
In a PV cell, photons are absorbed in the p layer. It's very
important to "tune" this layer to the properties of the incoming
photons to absorb as many as possible and thereby free as many
electrons as possible. Another challenge is to keep the electrons
from meeting up with holes and "recombining" with them before
they can escape the cell. To do this, we design the material so
that the electrons are freed as close to the junction as possible,
so that the electric field can help send them through the
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Short term course Proceedings on Renewable Energy
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"conduction" layer (the n layer) and out into the electric circuit. By maximizing all these characteristics,
we improve the conversion efficiency of the PV cell. The conversion efficiency of a PV cell is the
proportion of sunlight energy that the cell converts to electrical energy. To make an efficient solar cell,
we try to maximize absorption, minimize reflection and recombination, and thereby maximize
conduction. Today's PV devices convert 7%-17% of light energy into electric energy.
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INTRODUCTION TO WIND ENERGY
Growing concern for the environmental degradation has led to the world's interest in renewable energy
resources. Wind is commercially and operationally the most viable renewable energy resource and
accordingly, emerging as one of the largest source in terms of the renewable energy sector.
What is Wind Energy?
Wind is the natural movement of air across the land or sea. Wind is
caused by uneven heating and cooling of the earth's surface and by the earth's rotation. Land and water
areas absorb and release different amount of heat received from the sun. As warm air rises, cooler air
rushes in to take its place, causing local winds. The rotation of the earth changes the direction of the
flow of air.
Basic technology : Wind electric generator converts kinetic energy available in wind to
electrical energy by using rotor, gearbox and generator.
The Basic Process
: Wind can be used to do work. The kinetic
energy of the wind can be changed into
other forms of energy. The terms wind
energy or wind power describe the
process by which the wind is used to
generate mechanical power or
electricity. Wind turbines convert the
kinetic energy in the wind into
mechanical power. This mechanical
power can be used for specific tasks
(such as grinding grain or pumping
water) or a generator can convert this
mechanical power into electricity.
WIND MILL
WIND TURBINES
(Used to Mechanical Work)
(Used to generate electricity)
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Short term course Proceedings on Renewable Energy
How WIND ENERGY can be used to generate electricity?
2008
Blowing wind spins the blades
on a wind turbine -- just like a large toy pinwheel. This device is called a wind turbine and not a windmill.
A windmill grinds or mills grain, or is used to pump water.
The blades of the turbine are attached to a hub that is mounted
on a turning shaft. The shaft goes through a gear transmission
box where the turning speed is increased. The transmission is
attached to a high speed shaft which turns a generator that
makes electricity. If the wind gets too high, the turbine has a
brake that will keep the blades from turning too fast and being
damaged.
Types Of Wind Turbines:
1.
2.
Horizontal Axis Wind Turbine (HAWT)
vertical axis wind turbines (VAWT)
COMPONENT USED IN WIND TURBINES :
Advantages and Disadvantages of Wind Energy :



Advantages:
Clean fuel source : Wind turbines don't produce
atmospheric emissions that cause acid rain or
greenhouse gasses.
Wind energy is one of the lowest-priced
renewable energy technologies available today,
depending upon the wind resource and project
financing of the particular project
Wind turbines use only a fraction of the land.
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


Disadvantages:
Higher initial investment than fossil-fuel .
Wind energy cannot be stored (unless
batteries are used); and not all winds can be
harnessed to meet the timing of electricity
demands.
Noise produced by the rotor blades, aesthetic
(visual) impacts, and sometimes birds have
been killed by flying into the rotors.
Short term course Proceedings on Renewable Energy
2008
Anemometer: Measures the wind speed and transmits wind speed data to the controller.
Blades: Most turbines have either two or three blades. Wind blowing over the blades causes the blades to "lift"
and rotate.
Brake: A disc brake, which can be applied mechanically, electrically, or hydraulically to stop the rotor in
emergencies.
Controller: The controller starts up the machine at wind speeds of about 8 to 16 miles per hour (mph) and
shuts off the machine at about 55 mph. Turbines do not operate at wind speeds above about 55 mph because
they might be damaged by the high winds.
Gear box: Gears connect the low-speed shaft to the high-speed shaft and increase the rotational speeds from
about 30 to 60 rotations per minute (rpm) to about 1000 to 1800 rpm, the rotational speed required by most
generators to produce electricity. The gear box is a costly (and heavy) part of the wind turbine and engineers
are exploring "direct-drive" generators that operate at lower rotational speeds and don't need gear boxes.
Generator: Usually an off-the-shelf induction generator that produces 60-cycle AC electricity.
High-speed shaft: Drives the generator.
Low-speed shaft: The rotor turns the low-speed shaft at about 30 to 60 rotations per minute.
Nacelle: The nacelle sits atop the tower and contains the gear box, low- and high-speed shafts, generator,
controller, and brake. Some nacelles are large enough for a helicopter to land on.
Pitch: Blades are turned, or pitched, out of the wind to control the rotor speed and keep the rotor from turning
in winds that are too high or too low to produce electricity.
Rotor: The blades and the hub together are called the rotor.
Tower: Towers are made from tubular steel (shown here), concrete, or steel lattice. Because wind speed
increases with height, taller towers enable turbines to capture more energy and generate more electricity.
Wind direction: This is an "upwind" turbine, so-called because it operates facing into the wind. Other turbines
are designed to run "downwind," facing away from the wind.
Wind vane: Measures wind direction and communicates with the yaw drive to orient the turbine properly with
respect to the wind.
Yaw drive: Upwind turbines face into the wind; the yaw drive is used to keep the rotor facing into the wind as
the wind direction changes. Downwind turbines don't require a yaw drive, the wind blows the rotor downwind.
Yaw motor: Powers the yaw drive.
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Short term course Proceedings on Renewable Energy
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INTRODUCTION TO SOLAR EQUIPMENTS
Renewable energy sources such as wind and especially solar energy are being developed now to
counteract the problem of non-renewable sources disappearing. This energy will be more cost
effective and will not pollute the environment as fossil fuels have. Solar powered Equipment by
solar energy will become more readily available in the near future and could make life better for
literally everyone on the planet. Solar powered equipment is more cost-effective alternative
energy source.

The Advantages of Solar Powered Equipment: The sun releases as much energy to the
earth as there is in all of the known sources of non-renewable energy on the planet - solar
power released in only forty minutes of sunshine us equal to the energy used by earth’s
population in one year. We only harness on percent of the solar power we receive. Solar
energy has some good advantages in comparison to the other sources of power. Solar
radiation does not contaminate environment or endanger ecological balance. It avoids
major problems like exploration, extraction and transportation.

Self-sufficiency of Solar Powered Equipment : As costs from imported energy sources
such as oil continue to rise, most nations are in agreement that they should work towards
having the ability to supply enough energy to meet their own needs and decrease
dependence on foreign suppliers. Using solar energy through solar power equipment is a
prime example of this necessary self-sufficiency. Not only would someone using solar
powered equipment be relying only on his or her own energy source, each piece of the
equipment would be self-sufficient in and of itself. Each machine would theoretically
need only the amount of energy that it could collect for itself from the sun. Much of the
solar powered equipment available currently only uses solar energy as a backup or
auxiliary energy source and still relies on conventional energy for its primary operations.
As technology increases in the future, this will no longer by the case and solar powered
equipment will become truly self-sufficient.
Examples of Solar equipments :
1. Photovoltaic : Photovoltaic (PV) is the technical word for solar panels that
create
electricity.
Photovoltaic
material, most commonly utilizing
highly-purified silicon, converts
sunlight directly into electricity.
When sunlight strikes the material,
electrons are dislodged, creating an
electrical current which can be
captured and harnessed. The
photovoltaic materials can be several
individual solar cells or a single thin
layer, which make up a larger solar
panel.
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Short term course Proceedings on Renewable Energy
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2. Solar Thermal Electricity : Solar thermal electricity technologies (also
called concentrating solar power, or CSP) produce electric power by converting
the sun`s energy into high-temperature heat using various mirror configurations,
which is then channeled to an on-site power plant and used to make electricity
through traditional heat-conversion technologies. The plant essentially consists of
two parts: one that collects solar energy and converts it to heat, and another that
converts the heat energy to electricity.
3. Solar Enola : The solar enola use speed of warmed-up water in order to
reach the needed temperature, similar to the traditional heating system. This
may produce electric energy for house or industries.
4. Active solar water heating : Active solar water heating uses collectors,
usually on the roof of a building, to capture and store the sun’s heat via water
storage systems. The collectors provide heat to a fluid that circulates to a water
tank.
5. Solar panel : There are two types of solar panel
devices that collect energy from the sun:

Solar photovoltaic modules use solar
cells to convert light from the sun into
electricity.

Solar thermal collectors use the sun's energy to heat water or
another fluid such as oil or antifreeze
Why solar powered equipment is so cost effective : Unlike conventional energy, there
is no charge for the power itself, only the related equipment . But after the setup fee, barring a
nominal regular cost for maintenance, there are few expenses to solar power.
Obstacles to harnessing solar energy :

The non-availability
conditions .

Due to diffusion of Solar energy , there is requirement of large space in order to
convert it into useful forms . which entails a large capital investment for the conversion
apparatus.
of
solar energy
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during the night and during bad weather
Short term course Proceedings on Renewable Energy
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Solar Thermal Energy
Solar energy just means energy (light or heat) that comes from the sun. There are as many
different ways to use solar energy as you have ideas in your head.
What gets you hot lying on the beach on a summer day ? - Solar energy.
What gets your car hot when it's parked in the sun with the windows closed ? - Solar energy.
What makes your solar calculator go ? - Solar energy.
What makes the giant solar panels on satellites work ? - Solar energy.
What makes plants grow ? - Rain and... solar energy.
What makes the clouds that make the rain ? You got it! - Solar energy.
What sets a blade of glass under a magnifying glass on fire? Yup, solar energy. And on and on.
According to the need they are further categorized into three categories:
1 Low temperature collectors : Examples are ,
a. Solar Drier : It consists of wooden box with glass sheet at
the top. It works on the principle of green house effect. It is
used to dry cereals and vegetables.
b. Room Heater :It consist of a heat absorber fitted with glass
plates from one side air is allowed to enter and from other
side hot air is taken to room floor through pipe and floor gets heated.
c. Solar Cooker : It is used for cooking food by using sun’s heat
energy. It consist of a wooden box , glass plate kept on the
top to trap more heat, reflector to reflect more radiations, a
container to cook food.
2 Medium temperature collectors : Examples are Solar water
disinfection and Desalination .Solar water disinfection, also known
as SODIS, is a simple method of disinfecting water using only
sunlight and plastic PET bottles. SODIS is a cheap and effective
method for decentralized water treatment, usually applied at the
household level and is recommended by the World Health Organization
as a viable method for household water treatment and safe storage.
3
High temperature collectors : Examples are Solar power
and process heat. To achieve this in solar thermal energy plants,
solar radiation is concentrated by mirrors or lenses to obtain higher
temperatures — a technique called Concentrated Solar Power (CSP).
The practical effect of high efficiencies is to reduce the plant's
collector size and total land use per unit power generated, reducing
the environmental impacts of a power plant as well as its expense.
High temperatures also make heat storage more efficient, because
more watt-hours are stored per kilo of fluid. Since the CSP plant
generates heat first of all, it can store the heat before conversion to electricity. With current
technology, storage of heat is much cheaper and more efficient than storage of electricity. In
this way, the CSP plant can produce electricity day and night.
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Short term course Proceedings on Renewable Energy
Memories
of
Short-term course Renewable Energy
Chief Guest : Sh. S.K. Saxena & Sh. Jal Singh
Principal : Dr. J. L. Bhat
Convenor : Dr. Ravinder Pallakurthy & Dr. Mukesh Kumar
Chief Guest : Sh. S.K. Saxena
& Dr. Vinod Nautiyal
Students of B.Sc and participant of short term course
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2008
Short term course Proceedings on Renewable Energy
Published by
Dr. Mukesh Kumar
Convenor, ENERGY@SSNC
SWAMI SHRADDHANAND COLLEGE
University of Delhi
Alipur, DELHI-110036
28
2008