1. SHWETA SINGH
CHEMICAL ( V SEM)
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2. SOLAR ENERGY
1.Solar energy is an abundant and r
renewable energy source.
2.The use of solar energy in india has been
very limited. This is because it is dilute
energy source.
3.Energy must be collected over large area.
4.One way to overcome this problem is to
trap solar energy through the use of SOLAR
POND.
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3. WHAT A SOLAR POND IS
 A solar pond is a body of water that
collects and stores solar energy.
 Water warmed by the sun expands and
rises as it becomes less dense.
 Colder water moves down creating a
natural convective circulation that
mixes the water and dissipates heat.
 Its design reduces convection in order to
store heat collected by pond.
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4.  Salinity gradient prevents convection
current.
 Solar radiation reaches the lower layer
which contains conc. salt solution.
 Temperature in this layer rises but heat
is unable to move to surface by
convection.
 Solar heat is thus stored in the lower
layer of the pond.
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5. SOLAR
POND
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6. WORKING PRINCIPLE
 Sun’s rays heat the water and heated
water reaches the top and loses heat in
the atmosphere.
 Pond water remains at atmospheric
temperature.
 Solar pond restrict this tendency by
dissolving salt in bottom layer making it
too heavy to rise.
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7. MAIN FUNCTIONS OF SOLAR POND
 Collection of radiant energy and its
conversion into heat.
 Storage of heat.
 Transport of thermal energy out of the
system
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8. IN MAN MADE SOLAR POND
 The bottom of the pond is lined with
durable plastic liner such as black
polythene.
 Dark surface at the bottom increases the
absorption of solar radiation.
 Salts like sodium chloride and
magnesium chloride dissolved in
bottom for making it denser.
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9. SOLAR POND CONSISTS OF 3
ZONES
 An upper convective zone of clear fresh
water that acts as solar receiver.
 A gradient which serves as the non-
convective zone.
 Lower convective zone with the densest
salt concentration serving as the heat
storage zone
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11. APPLICATION
 Salt production
 Aquaculture,using saline or fresh water
 Dairy industry(to preheat feed water to
boilers)
 Fruits and vegetable canning industry
 Grain industry(for grain drying)
 Water supply(for desalination)
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12. PROCESS HEAT
 Scope for process heat applications(i.e
water heated to 80 to 90 degree
celcius),when a large quantity of hot
water is required such as textile
processing and dairy industries.
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13. DESALINATION
 Solar ponds can provide a
cost effective solution to
the portable drinking
water problems,
desalination cost work
out to be 7.5 paisa per
litre , in coastal villages
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14. REFRIGERATION
 Life saving drugs like vaccines can be
preserved for long time in cold storage
using solar pond technology in
conjunction with ammonia based
absorption refrigeration system.
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15. BHUJ SOLAR POND
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16. ADVANTAGES
 Low investment cost per installed
collection area.
 Thermal storage is incorporated into the
collector and is of very low cost.
 Can operate in almost any climate.
 Can store solar heat much more
efficiently than a body of water of same
size.
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17. DISADVANTAGES
 Require a specific location that is not
readily available in all areas.
 Excessive wind can blow water away or
evaporate the top layer of water at high
rate.
 Risk of contamination of ground with
high salt levels from water in pond.
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18. CONCLUSION
 Solar ponds can be effectively used as
replacements in industries that use
fossil fuels to generate energy. Solar
ponds can be used for process heating,
refrigeration, water desalination etc. It
will be the future energy source.
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19. THANK YOU
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