1. JOURNAL OF INFORMATION, KNOWLEDGE AND RESEARCH IN
MECHANICAL ENGINEERING
ISSN 0975 – 668X| NOV O9 TO OCT 10 | VOLUME – 01, ISSUE - 01 Page 32
POTENTIAL OF SOLAR ENERGY : SOLUTION OF
ENERGY CRISIS -- A REVIEW
PROF. R. D. PARMAR
Lecturer, Electrical Engineering Department, C.U.Shah Polytechnic, Surendranagar,
Gujarat, India
raghuvir_dhirubha@yahoo.com
ABSTRACT : Taking into account the growth in global energy consumption, world energy problems are of
major importance and utilisation of the conventional carriers of energy must be limited. For mankind to survive
on the earth in the nearby future energy source other than fossil fuels must be developed. A solar radiation is a
non exhausting reservoir of energy.The part of solar energy reaching the earth atmosphere is about 1018
kWh/year. This energy is higher than energy stored in all recognised fossil fuels sources. In this review energy
crisis and potential of solar energy is discussed to solve crisis along with advantages and disadvantage of solar
energy.
INTRODUCTION:
Almost upto 1850, main sources of energy were
wood, energy of wind, running water, energy of
animals and men.About 150 years ago people started
to use fossil fuels: coal, oil and gas. About 50 years
ago nuclear fission of uranium became an important
sourceof energy. All these sources of energy are non
renewable. Growing exploitation results not only in
their depletion but creates serious ecological
problems.Oil,gas and coal are raw materials for
chemical industry and should be stored for future
generation.Fossil fuels mentioned above (besides
uranium) have been created as a result of
photosynthesis and biological processes - it means as
a result of the sun activity in previous epochs.
The world population is still rapidly growing, and
some studies predict a world population of 9 billion
around 2040 in reference to the 7 billion people
living on this planet today.All these people will need
energy, which increases the global energy demand.In
addition, the energy consumption per capita is linked
to the living standard of a country.
This very serious energy situation is understood
allover the world now. A big effort is being done in
developed countries in the field of exploitation of
renewable energy sources including solar energy,
wind and water energy, geothermal energy as well as
otherkinds of renewable sources.
Around 1.2 billion out of the 7 billion people world-
wide still do not have access to the electricity
grid.65% of the electricity is coming from fossil
fuels, where coal is the dominant contributor. Nuclear
is responsible for 16% of the world's electricity
generation and hydro-power is with 19% - the largest
contributor among the renewable energy sources.In
the conversion from chemical and nuclear energy to
electricity,two thirds of the energy is lost.One third
ends up in the form of electricity.40% of the electric
energy is used for residential purposes and 47% is
used by industry.13% is lost in transmission.
Till date, transport do not play a significant role in
the electricity consumption.However, it is expected
that transport related electricity consumption will
increase in the coming decades, as well.In 2007,
20200 TWh of electricity was generated world-
wide.1 trillion GWh reach the earth’s surface per year
from sun to earth within 8 minutes only which is
roughly 10000 times the world’s primary energy
demand[4],but the biggest question is to tap all that
energy.
THE SOLAR POTENTIAL :
There is more than enough solar radiation available
around the world to satisfy the demand for solar
power systems. The proportion of the sun’s rays that
reaches the earth’s surface is enough to provide for
global energy consumption 10,000 times over.The
greater the available solar resource at a given
location, thelarger the quantity of electricity
generated. Tropical regions offer a better resource
than more temperate latitudes. The average
irradiation in Europe is about 1,000 kWh per square
metre and year, for example, compared with 1,800
kWh in the MiddleEast.Using today’s PV
technology, an array field that is 300 miles on each
side could produce the entire electrical energy used
by the U.S. in a year[5]
As Solar Energy technology becomes increasingly
affordable and available, its potential as a major
source of low-carbon energy grows. In a 2004 report
entitled, “Solar Generation” [Greenpeace and the
European Photovoltaic Industry Association (EPIA)],
estimated that, by 2020, Photovoltaic systems could
provide 276*10^6 MWh of energy-equivalent to 1%
of the global demand projected by the International
Energy Agency (IEA).The study assumed that the
Photovoltaic systems market would grow at a
compound annual growth rateof 30% until 2020, well
below the 45% growth that the industry averaged
from 2002 to 2007. This would prevent the emission
of 664 million tons of CO2 annually. Moreover, the

2. JOURNAL OF INFORMATION, KNOWLEDGE AND RESEARCH IN
MECHANICAL ENGINEERING
ISSN 0975 – 668X| NOV O9 TO OCT 10 | VOLUME – 01, ISSUE - 01 Page 33
report found that with a 15% growth rate from 2020
to 2040, the solar energy output could be more than
9000*10^6 MWh, which would be 26% of the
projected global demand.
Total spectrum of electromagnet energy emitted by
the sun is defined as solar radiation energy or
insolationor sunlight.A small fraction of this energy
hits the Earth. The sunlight that hits the earth’s
surface contains visible light, infrared and ultraviolet
light.Travelling time for sunlight from the sun to
earth is approximately about 8 minutes.
The net mass before and after a fission or fusion
process is negative; in other words, there is a loss of
mass in a nuclear reaction. This mass does not just
disappear, but is converted into energy.‘
Nuclear fusion of hydrogen into helium is the process
due to which sun gives us energy. In fact, the Sun
fuses about 620 million metric tons (almost 1.4
billion pounds) of hydrogen into helium every
second.
99% of the energy from nuclear fusion is generated
inside 24% of the Sun’s radius, which flows outwards
through several different layers, before it escapes as
sunlight. A little further out, there is no nuclear
fusion taking place at all.Over its lifetime, a typical
PV module, in a sunny climate, will produce over
twenty times the electricity initially used to
manufacture it.
The sun has been burning for several billion years
already. The continual loss of mass caused by nuclear
fusion means that the sun is slowly disappearing. But
don’t worry; according to NASA the Sun has another
6.5 billion years worth of fusion processes left before
it shuts down.
174 petawatts (PW) of energy comes in form of solar
radiation (or insolation) hits our atmosphere. Almost
one third of this is reflected back into space. The rest,
3 850 000 exajoules (EJ) every year, is absorbed by
the atmosphere, clouds, oceans and land. This
amount of energy is equivalent to 40 000 times the
total energy consumption in the United States, 8000
times the total consumption in the whole world.One
hour of insolation is the equivalent to more than the
world’s energy consumption for an entire year.
Unfortunately, harnessing all this energy is not
achievable.Solar power is greener than conventional
ways of harnessing energy sources such as fossil
fuels and coal.
Solar energy is by far the largest energy resource on
the Earth.Here are some other interesting
comparisons to help make you grasp the massive
potential of solar energy:One year’s worth of solar
energy reaching the surface of the Earth would be
twice the amount of all non-renewable resources,
including fossil fuels and nuclear uranium.
The solar energy that hits the Earth every second is
equivalent to 4 trillion 100-watt light bulbs.The solar
energy that hits one square mile in a year is
equivalent to 4 million barrels of oil.
In comparison, only 1% of the electricity
consumption in the U.S. can be sourced back to the
United States. This number is steadily growing and is
expected to help replacing fossil fuels in the long run.
Solar power generation:
Solar PV systems converts sunlight directly into
electricity.When PV modules are exposed to
sunlight,they generate Direct current (D.C.)
electricty.An inverter then converts D.C. into
Alternating current (A.C.) electricity.A solar PV cell
is the smallest semiconductor device which converts
sunlight into electrical energy. A module is an
assembly of cells in series or parallel to augment
voltage and/or current. A panel is an assembly of
modules on a structure. An array is an assembly of
panels at a site. [5]
Advantages of Solar Energy :
1. Renewable
According to astrophysics, the Sun was born about
4.57 billion years ago and has another 6-7 billion
years before it becomes a white dwarf (a planetary
stage where nuclear fuel in the star is exhausted).
2. Abundant
The potential of solar energy is beyond
imagination. The surface of the earth receives
120,000 terawatts of solar radiation (sunlight) –
20,000 times more power than what is needed to
supply the entire world.
3. Sustainable
An abundant and renewable energy source is also
sustainable. Sustainable energy sources meet the
needs of the present without compromising the ability
of future generations to meet their needs. In other
words, solar energy is sustainable because there is no
way we can over-consume.
4. Environmentally Friendly
Harnessing solar energy does generally not cause
pollution. However, there are emissions associated
with the manufacturing, transportation and
installation of solar power systems – almost nothing
compared to most conventional energy sources. It is
clear that solar energy reduces our dependence on
non-renewable energy sources. This is an important
step in fighting the climate crisis.
5. Good Availability
Solar energy is available all over the world. Not only
the countries that are closest to the Equator can put
solar energy to use – Germany, for example, has by
far the highest capacity of solar power in the world.
6. Reduces Electricity Costs
With the introduction of net metering and feed-in
tariff (FIT) schemes, homeowners can now “sell”
excess electricity, or receive bill credits, during times
when they produce more electricity than what they
actually consume.
7. Many Applications
8. Silent
9. Financial Support from Government/State
10. Low Maintenance
11. Technology is improving

3. JOURNAL OF INFORMATION, KNOWLEDGE AND RESEARCH IN
MECHANICAL ENGINEERING
ISSN 0975 – 668X| NOV O9 TO OCT 10 | VOLUME – 01, ISSUE - 01 Page 34
Disadvantages of Solar Energy:
Expensive,Intermittent,Energy Storage is
Expensive,Requires Space,there are issues regarding
manufacturing of the solar panels, as well as disposal
and recycling of byproducts.
Emissions of greenhouse gases do take place during
the manufacturing. Dangerous climate gases such
as nitrogen trifluoride and sulfur hexafluoride are
both on the list. These literally have many thousand
times the impact on global warming as an equal
amount of carbon dioxide would.
REFERENCES:
1) Conference paper of R.TRYKOZKO, Institute of
Physics, Warsaw University of Technology,
Warszawa, Poland on“Principles of photovoltaic
conversion of solar energy'”,1997
2) “Solar generation :solar electricity for over one
billion people and two million jobs by
2020”,september 2006,GREENPEAKS,,European
photovoltaic industry association
3) “Solar Generation” by Greenpeace and the
European Photovoltaic Industry Association (EPIA),
2004 report
4) “High quality polysilicon – The basis for high
wafer yields and high efficiency solar cells” by
WACKER POLYSILICON, capital markets day,
Burghausen, July 25, 2007
5) “Crystalline silicon solar cell technology” by
Rubin Sidhu, Dacid E.Carlson, BP solar, 2010
6) “Energy and global economic crisis: The chances
for progress,10 papers for Barcelona 2010”by George
Joffe, Samir Allal and Houda Ben Jannet
Allal,Institute for security studies,European union
and European institute for Mediterranean,October
2009
7) Averting the next energy crisis: The demand
challenge, McKinsey Global Institute, Mar 2009
8): Energy crisis: Will technology save us?” By
JOHN ZIAGOS, LLNL Scientist, KEN WEDEL,
March 24, 2007
9)”World energy outlook” by International agency,
2009
REVIEW PAPER PUBLISHED ON : 13/05/2010