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SYLLABUS:
Unit I SOLAR RESOURCES :
Passage through the atmosphere;
global distribution; optimal system
geometry, Insolation amount
available on earth; Resource
estimation; Solar data; Solar
radiation spectrum; Seasonal and
daily variation; Effect of Tilt Angle.
Unit II SOLAR PHOTOVOLTAICS:
The Photo Voltaic effect; Spectral
response; p-n junction; different
types of photovoltaic cells; PV cell
characteristics; Effect of variation of
temperature; insolation level & tilt
angle on the characteristics;
equivalent circuits; temperature
effects on conversion efficiency;
Fabrication and costs of PV cell.
Unit III SOLAR THERMAL:
Principles of applied heat transfer,
solar thermal collectors: Glazing,
evacuation, selective surfaces,
concentrators. Solar thermal
applications: water and space
heating; solar ponds; dryers;
distillation; solar cooker. Passive
Solar design.
Unit IV SOLAR PHOTOVOLTAIC
SYSTEMS:
Photovoltaic modules; module
specifications; module hot spots;
bypass diodes; PV arrays and PV
systems; cabling; earthling and
lightning protection. Battery
storage: Lead and Nickel cadmium
batteries; Charge regulators; LVD
circuit; Voltage and current Source
Inverters. Tracking Systems;
Maximum power point tracking.
Unit V SYSTEM APPLICATIONS :
Autonomous PV system; Grid Linked
PV systems; Remote application of
Photovoltaic’s; System sizing;
System Performance; Economics
and future prospects.
Text Books:
1. Solar Energy: Principles of Thermal Collection and
Storage by S.P.Sukhatme: TMH
2. Solar Energy Utilization Volume-1 &2 by G.D.Rai- Khanna
Publishers
Reference Books:
1. Solar Electricity Handbook-2010 By Micheal Boxwell –
Green Stream publishing
2. Non conventional Energy by G.D.Rai- Khanna Publishers
Unit -I SOLAR RESOURCES
 Passage through the atmosphere
& global distribution
 optimal system geometry
 Insolation amount available on earth
 Resource estimation; Solar data
 Solar radiation spectrum; Seasonal and
daily variation
 Effect of Tilt Angle.
Electricity sector in India
The electricity sector in India supplies
the
world's
6th
largest
energy
consumer, accounting for 3.4% of global
energy consumption by more than 17%
of global population.
The
Energy
policy
of
India
is
predominantly
controlled
by
the Government of India's, Ministry of
Power, Ministry of Coal and Ministry of
New
Renewable
Energy
and
administered locally by Public Sector
Undertakings (PSUs).
WIND-SOLAR-DIESEL
TRI-BRID POWER
SYSTEM
Power Center
& Inverter
Wind Generator
(5 kVA)
Solar Panels
(Total 5 kVA)
75 W/Panel
45 Panels
DG Set (5 kVA)
Data Center
Battery Bank (60 Nos)
64.75% from thermal power plants,
21.73% from hydroelectric power plants,
2.78% from nuclear power plants.
& 10.73% from Renewable Energy Sources.
More than 50% of India's commercial energy
demand is met through the country's
vast coal reserves.
The country has also invested heavily in recent
years
in
renewable
energy
utilization,
especially
wind energy. In 2010, India's
installed wind generated electric capacity was
13,064 MW. Additionally, India has committed
massive amount of funds for the construction
of various nuclear reactors which would
generate at least 30,000 MW.
In July 2009, India unveiled a $19 billion plan to
produce 20,000 MW of solar power by 2022.
Due to the fast-paced growth of India's
economy, the country's energy demand has
grown an average of 3.6% per annum over
the past 30 years. In December 2010, the
installed power generation capacity of India
stood at 165,000 MW.
The Indian government has set a modest
target to add approximately 78,000 MW of
installed generation capacity by 2012 .
The total demand for electricity in India is
expected to cross 950,000 MW by 2030.
Total Installed Capacity (as on 28-02-2011)
is 171,926.40 MW
Renewable energy in India is a sector that is
still undeveloped. India was the first
country in the world to set up a ministry
of non-conventional energy resources, in
early 1980s.
However its success has been very spotty.
In recent years India has been lagging
behind other nations in the use of
renewable energy (RE). The share of RE in
the energy sector is less than 8% of
India's total energy needs. Renewable
energy in India comes under the purview
of the Ministry of New and Renewable
Energy.
Solar power in India
The first Indian solar thermal power
project (2X50MW) is in progress in
Phalodi (Rajasthan), and is
constructed by CORPORATE ISPAT
ALLOY LTD.
The solar thermal power plant has cost
4 times as much as the coal based
steam thermal power plant.
India's largest photovoltaic (PV) power plants
Name of Plant
DC
Peak Power (MW)
Notes
Sivaganga Photovoltaic Plant
5
Completed December 2010
Kolar Photovoltaic Plant
3
Completed May 2010
Itnal Photovoltaic Plant, Belgaum
3
Completed April 2010
Azure Power - Photovoltaic Plant
2
2009
Jamuria Photovoltaic Plant
2
2009
NDPC Photovoltaic Plant
1
2010
Thyagaraj stadium Plant-Delhi
1
April, 2010
Gandhinagar Solar Plant
1
January 21, 2011
Tata - Mulshi, Maharashtra
3
Commissioned April 2011
Azure Power - Sabarkantha, Gujarat
5
Commissioned June 2011
Moser Baer - Patan, Gujarat
Tata - Mayiladuthurai, Tamil Nadu
30
1
To Be Commissioned July 2011
Commissioned July 2011
What is Solar Energy?
Originates with the thermonuclear fusion
reactions occurring in the sun.
Represents the entire electromagnetic radiation (visible light,
infrared, ultraviolet, x-rays, and radio waves).
Advantages and Disadvantages
•
Advantages
•
Disadvantages
• All chemical and radioactive polluting byproducts of
the thermonuclear reactions remain behind on the
sun, while only pure radiant energy reaches the
Earth.
• Energy reaching the earth is incredible. By one
calculation, 30 days of sunshine striking the Earth
have the energy equivalent of the total of all the
planet’s fossil fuels, both used and unused!
• Sun does not shine consistently.
• Solar energy is a diffuse source. To harness it, we
must concentrate it into an amount and from that we
can use, such as heat and electricity.
• Addressed by approaching the problem through:
1) collection, 2) conversion, 3) storage.
Passage through the
atmosphere
How much solar energy?
The surface receives about 51% of the total
solar energy that reaches the Earth. Only
this amount is usable.
At any given point on Earth the amount of insolation
(solar energy) available to heat the surface
depends on 3 factors :
1) Angle of Insolation
2) Duration of Insolation
3) Energy Absorption and Reflection by the
atmosphere and Earth’s surface
These Factors Effect the intensity of Insolation: at
a given point, the greater the intensity, the
higher the average temperature of that location
1.)Angle of Insolation (AOI)
The angle of the sun’s rays hitting the earth
Measured from the Horizon up to position of the sun
-This angle is dependent on:
A.)Time of day: Noon has the greatest Angle of Ins.
When the sun is most directly overhead: At 90ͦ, the
sun hits the earth perpendicularly= Vertical Rays
B.)Tilt of the Earth:
Greater AOI when the sun
is directly overhead (90ͦ
AOI)
C.)Latitude: only between
the equator and tropics it is
possible for the suns rays to
be vertical (directly
overhead)
How the angle at which light hits the surface effects
INTENSITY
2.)Duration of Insolation (DOI)
= time from sunrise to sunset
Rule of thumb: Any point on earth receives the most heat
when the sun is highest in the sky and when the duration
is the longest (longer days) *Duration varies with seasons
and Latitude.
Greatest DOI is on June
21st-The further north
you go, the longer the day
lasts (NY=42ͦ N)
Equinoxes
Sun is directly overhead
Spring(March 21): at 0ͦ
Fall (Sept. 23): at 0 ͦ
Solstices
Summer(June 21):23 ½ ͦ N
Winter (Dec 21): 23 ½ ͦ S
Absorption of Insolation (solar energy)
• Darker objects absorb energy faster than lighter but
lose energy faster (Easy Come, Easy Go) (Ex: Land and
Sea)
• The Atm:Ozone absorbs short wave radiation (gamma,
beta x-rays) H20(g) and CO2 absorb long wave radiation
(infrared)
• Land and water ABSORB visible light and reradiate this
solar energy back
out as infrared
(long wave)
TERRESTRIAL
radiation
Solar Energy Potential
• As of February 2006, Photovoltaic
technology accounted for less than 1% of
worldwide electricity generation.
• The amount of solar energy that reaches
the Earth’s surface every hour is greater
than humankind’s total demand for energy
in one year
SOLAR RADIATION
Atmospheric Effects: Solar radiation is absorbed,
scattered and reflected by components of the
atmosphere.
The amount of radiation reaching the earth is less
than what entered the top of the atmosphere.
We classify it in two categories:
Direct Radiation: radiation from the sun that
reaches the earth without scattering.
Diffuse Radiation: radiation that is scattered by
the atmosphere and clouds.
Solar Radiation
Solar Radiation Measurement:
Measurement of solar radiation are
important because of increasing number
of solar heating and cooling applications
and the need for accurate solar irradiation
data to predict performance.
Two types of instruments:
1. Pyreheliometer
2. Pyranometer
SOLAR RADIATION DATA
Most of the data on solar radiation received on the
surface of the earth are measured by solarimeter
which give readings for instantaneous measurements
at rate throughout the day total radiation on a
horizontal surface.
India lies between latitude 7o and 37oN and receives an annual
average intensity of solar radiation between 16700-29260
KJ/m2/day (400-700 Cal/Cm2/day).
Peak values are generally measured in April or May with parts
of Rajasthan and Gujarat receiving over 25100 KJ/m2/day (600
Cal/Cm2/day).
During the monsoon and winter months the daily solar
radiation decreases to about 16700 KJ/m2/day (400
Cal/Cm2/day).
The annual daily diffuse radiation received over the whole
country is observed to be about 7300 KJ/m2/day .
The minimum values of diffuse radiation measured over many
parts of the country during Nov & Dec are between 3135-4180
KJ/m2/day while maximum values measured over the whole
country are about 12550 KJ/m2/day specially in July in Gujarat.
l
Estimation of Average So ar
Radiation:
Monthly average horizontal solar radiation Hav was given by
Angstrom (1924) is
' 
'
' n 


H av  H o a  b


N 

'
'
where a & b are arbitrary
constants
'
'
( Freitz 1951 ; a  0 . 35 , b  0 . 61 )
'
H o  the monthly avg . horizontal
solar radiation
for
a clear day
n  avg . daily hours of bright sunshine
for same period
N  max .. daily hours of bright sunshine
for same period
Constant a and b for some Indian Towns
Location
a
b
Location
a
b
Ahmadabad
0.28
0.48
Mangalore
0.27
0.43
Bangalore
0.18
0.64
Shillong
0.22
0.57
Baroda
0.28
0.48
Srinagar
0.35
0.40
Bhopal
0.27
0.50
Trivendrum
0.37
0.39
Calcutta
0.28
0.42
Vishakhapatnam
0.28
0.47
Jodhapur
0.33
0.46
New Delhi
0.25
0.57
Madras
0.30
0.44
Roorkee
0.25
0.56
Array orientation is defined by two angles:
1. Tilt angle is the vertical angle between the horizontal
and the array surface.
• Maximum energy gain will be achieved by orienting the array
surface at a tilt angle close to the value of the local latitude –
In high latitudes arrays should be very steep and vice versa.
• For optimal performance the tilt angle should be adjusted
from the latitude angle by an amount equal to the average
declination during that time.
• During the summer the average declination is +15º, so we
should have a tilt of latitude minus 15º to make the array
perpendicular to the average solar path –during the summer.
• Array Azimuth angle will be optimal when that array is due
south.
• Sun trackers allow the PV array to change the tilt angle, the
azimuth angle, or both –generally is not considered cannot
be made cost effective.

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