What is Solar Energy ??
Solar energy is energy that is derived
from the suns rays. The light and
the heat provided by the sun is
“collected” or harnessed by solar
panels and then converted into a
more useful form of energy. There
are two main forms of solar energy –
passive solar energy and active solar
Uses of Solar Energy in various
-> Solar energy is frequently used to power the radio and TV station as it is
reliable, renewable, affordable, and need less maintenance. Solar energy is also
used to supply power to lighthouse and warning light for aircraft.
-> Solar energy is also used for public transportation such as trolleys, buses
-> Remote building like school, community hall and clinic also use the solar
energy. Specialized water pump is used which run on solar energy to pump
water in remote area for portable water supply. Large scale desalination plant
also use power generated from solar energy instead of electricity.
Uses of Solar Energy in heating
water- ‘Solar Heating’
Sunlight is Earth's primary
source of energy.
The solar constant is the
amount of power
that the Sun deposits per
that is directly exposed to
The solar constant is
~1,370 watts per square
or ~1273 watts per 10
Solar Water Heating !!
Heat water for your home using energy
from the sun.
Solar water heating systems use free
heat from the sun to warm domestic hot
water. A conventional boiler or immersion
heater can be used to make the water
hotter, or to provide hot water when solar
energy is unavailable.
Hot water throughout the year: The
system works all year round, though
you'll need to heat the water further
with a boiler or immersion heater
during the winter months.
Cut your bills: Sunlight is free, so
once you've paid for the initial
installation your hot water costs will be
Cut your carbon footprint: Solar hot
water is a green, renewable heating
system and can reduce your carbon
Benefits of Solar Heating !!
Solar water heating systems use solar panels,
called collectors, fitted to your roof. These
collect heat from the sun and use it to heat
up water which is stored in a hot water
cylinder. A boiler or immersion heater can be
used as a back up to heat the water further
to reach the temperature you want.
There are two types of solar water heating
-> evacuated tubes (as in the picture above)
-> flat plate collectors, which can be fixed on
the roof tiles or integrated into the roof.
How do solar water heating
How to heat up water using Solar
Energy with bottles !!
-> Cut the bottoms out of large plastic bottles, the
wider the better.
-> Thread the bottles onto a hose
-> Run the water through the hose slowly and it
will come out warm.
-> Wait about one an hour for the air in the
bottles to heat up
Lay the hose out in full sunlight, run a
little water through it to make sure there is
water resting throughout the length of the
Use of Solar heating in Large
-> Solar water heaters—
also called solar domestic
hot water systems—can
be a cost-effective way to
generate hot water for
-> Solar water heating systems
include storage tanks and solar
collectors. There are two types
of solar water heating systems:
active, which have circulating
pumps and controls, and passive,
Integral collector-storage systems
Also known as ICS or batch systems, they feature one or
more black tanks or tubes in an insulated, glazed box. Cold
water first passes through the solar collector, which
preheats the water. The water then continues on to the
conventional backup water heater, providing a reliable
source of hot water
Three types of solar collectors are used for
Glazed flat-plate collectors are insulated, weatherproofed
boxes that contain a dark absorber plate under one or more
glass or plastic (polymer) covers.
Evacuated-tube solar collectors
They feature parallel rows of transparent glass tubes.
Each tube contains a glass outer tube and metal absorber
tube attached to a fin. The fin's coating absorbs solar
energy but inhibits radiative heat loss
There are two types of active solar water
Direct circulation systems
Pumps circulate household water through the
collectors and into the home. They work well in
climates where it rarely freezes.
Indirect circulation systems
Pumps circulate a non-freezing, heat-transfer
fluid through the collectors and a heat
exchanger. This heats the water that then
flows into the home. They are popular in
climates prone to freezing temperatures.
Use of Solar Energy in
in other applications !!
A solar vehicle is an electric vehicle
powered completely or significantly by
solar energy . Usually, photovolatic (PV)
cells contained in solar panels convert the
sun's energy directly into solar energy.
The term "solar vehicle" usually implies
that solar energy is used to power all or
part of a propulsion. Solar power may be
also used to provide power for
communications or controls or other
Use of Solar Vehicles !
Solar lighting especially for outdoors is very
common today. Lighting walkways and other
landscape is a simple matter. Most home
improvement stores now offer solar powered
outdoor lighting. The use of solar power
doesn’t end there. Solar powered outdoor
lighting is on a small portion of capturing the
sun’s power for our energy. You can use solar
energy for cooking, heating and cooling your
home, water heating space heating, and even
total solar energy systems to generate your
own electricity. From very simple to complex
grid systems solar power is available to the
Use of Solar Energy
Top 10 countries using
1. Germany (9,785 MW) -
2. Spain (3,386 MW) -
3. Japan (2,633 MW) -
4. United States (1,650 MW) -
5. Italy (1,167 MW) -
6. Czech Republic (465 MW) -
7. Belgium (363 MW) -
8. China (305 MW) -
9. France (272 MW) -
10. India (120 MW) -
Facts on Solar Energy!!!
-Solar Energy is measured in kilowatt-
hour. 1 kilowatt = 1000 watts.
-1 kilowatt-hour (kWh) = the amount of
electricity required to burn a 100 watt
light bulb for 10 hours.
-According to the US Department of
Energy, an average American household
used approximately 866-kilowatt hours
per month in 1999 costing them
-About 30% of our total energy
consumption is used to heat water.
-> After initial investment, all the electricity you
produce is free
-> Incentives and Rebates from governments and
utility companies offset the initial investment
-> new financing vehicles such as leasing and Pace
offset the initial investment while preserving the
incentives and rebates
-> Net metering gives you the opportunity of selling
your excess electricity or getting a credit from the
-> reduce or completely eliminate your electric bill
cost of solar panels are decreasing while efficiency
Advantages of using
Solar Energy !!
Disadvantages of Solar
-> high initial cost to purchase solar panel
-> a relatively large area is required to install a
-> the highest efficiency is dependent on full sun
-> no electricity can be produced at night, and
reduced production on cloudy/rainy days