This slide is about solar pond. A sustainable, environmental and natural water heater or energy collector.

1. By:- Shivang Parmar
Solar Pond

2. Solar Pond
About Solar Energy
Why use solar pond
About Solar Pond
How work solar pond
Advantages of solar pond
Disadvantages of solar pond
Application of solar pond
conclusion

3. › Many Renewable free source is available in our earth
› Like solar , Wind , Hydro , Tidal , Geothermal , Biomass , etc..
› Solar energy is more uses then other Energy's.
› Now we are Talking About solar energy.
› Solar Energy is Coming from sun.
› Solar Energy is biggest Renewable source of our Earth.
› We are using this energy for many works.
› We are use in our home daily for making food , for boil water, for electricity, etc..
› Other uses of solar energy is Heating , Cooling , Ventilation , Water Treatment , Molten
Salt Technology , Architecture and urban planning , Agriculture and horticulture ,
Transport , Fuel production , etc…..
› Now , I am telling about solar pond.
Solar Energy

4. Why we use Solar Pond
 As we know solar energy is widely freely available, and is said to be
future energy as it is renewable energy.
 Solar energy is free ,but the devices and methods of storing solar
thermal energy are very expensive.
 Had you ever thought of storing the solar thermal power without any
expensive solar storage devices?
 SOLAR POND, is a one of method for trapping and storing solar energy
and using it later as the input for thermal power generation plant.

5. • A pool of saltwater which acts as a large-scale solar thermal energy collector It includes
an integral heat storage for supplying thermal energy.
• When the sun's rays contact the bottom of a shallow pool, they heat the water adjacent
to the bottom. When water at the bottom of the pool is heated, it becomes less dense
than the cooler water above it, and convection begins. Solar ponds heat water by
impeding this convection. Salt is added to the water until the lower layers of water
become completely saturated. High-salinity water at the bottom of the pond does not mix
readily with the low-salinity water above it, so when the bottom layer of water is heated,
convection occurs separately in the bottom and top layers, with only mild mixing
between the two. This greatly reduces heat loss, and allows for the high-salinity water to
get up to 90 °C while maintaining 30 °C low-salinity water. This hot, salty water can then
be pumped away for use in electricity generation, through a turbine or as a source of
thermal energy.
Solar Pond

6. Solar Pond
o The largest operating solar pond for electricity generation was the Beit HaArava pond built in
Israel and operated up until 1988. It had an area of 210,000 m² and gave an electrical output of
5 MW.
o India was the first Asian country to have established a solar pond in Bhuj, in Gujarat. The project
was sanctioned under the National Solar Pond Program by the Ministry of Non-Conventional
Energy Sources in 1987 and completed in 1993 after a sustained collaborative effort by TERI, the
Gujarat Energy Development Agency, and the GDDC (Gujarat Dairy Development Corporation
Ltd).
o The solar pond successfully demonstrated the expediency of the technology by supplying 80,000
litters of hot water daily to the plant. It is designed to supply about 22,000,000 kWh of Thermal
Energy annually . The Energy and Resources Institute provided all technical inputs and took up
the complete execution of research, development, and demonstration. TERI operated and
maintained this facility until 1996 before handing it over to the GDDC.
o There is Two types of Solar pond
o CONVECTING SOLAR PONDS
o NON-CONVECTING SOLAR PONDS

7. Bhuj Solar pond
Beit HaArava solar pond

8. Construction of Solar Pond
 We know that fluids such as water and air rise up when heated.
 Solar ponds stops this process when large quantity of salt are dissolved in hot
bottom layer of the pond, making it too dense to rise to surface and cool down.
 Solar pond consists of three main layers. The top layer is cold and has little salt
content. The bottom layer is hot,70-80°C , and last layer is very salty.
 Separating these two layers is important gradient zone. In this salt content
increases with increase in depth. Water in gradient zone can’t rise, because water
above it has less salt content and is therefore lighter.
 Similarly, water can’t fall because water below it has a higher salt content and is
heavier.
 Thus the stable gradient zone act as a transparent insulator, permitting sunlight to
be trapped in the hot bottom layer, from which useful heat is withdrawn.

9.  When solar radiation strikes the pond, most of it is
absorbed by the layer at the bottom of the pond.
 The temperature of the pond is increases because
dense salt layer.
 If the pond contained no salt, the bottom layer
would be less dense than the top layer as the
heated water expands. The less dense layer would
then rise up and the layers would mix.
 But the salt density difference keeps the ‘layers’ of
the solar pond separate.
 The denser salt water at the bottom prevents the
heat being transferred to the top layer of fresh water
by natural convection, due to which the temperature
of the lower layer may rise to as much as 95°C.
How work Solar Pond

10. Energy-Cost Comparison

11. Advantages of Solar Pond
 Low investment costs per installed collection area.
 Thermal storage is incorporated into the collector and is of very low cost.
 Diffuse radiation (cloudy days) is fully used.
 Expensive cleaning of large collector surfaces in dusty areas is avoided .
Environment friendly energy – no pollution!
Reliable energy source.
Stores heat, so it can be used 24*7*365.
Low maintenance costs.
A separate collector system is not needed in a solar pond setup.
The heat stored is on a very large scale and hence it can be used day and
night, no storage is necessary in the form of batteries.
The accumulated salt crystals which is a by-product from solar pond can
be used further.
Can operate in almost any climate.

12. Disadvantages of Solar Pond
 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
 Low efficiency
 Space availability
 Salt and water supply needed
 Low efficiency due to:
 Heat losses
 Bottom losses
 Top losses
 Radiation losses
 The accumulated salt crystals have to be removed periodically and this adds
maintenance expense.
 Solar ponds require a significant amount of land area to function properly.

13. Application of Solar Pond
Process heat
Desalination
Refrigeration
Salt production
Aquaculture, using saline or fresh water
Dairy industry
Fruit and vegetable canning industry
Fruit and vegetable drying
Grain industry
Water supply

14. Alternative source of Solar Pond
• Solar Gel Pond
• Equilibrium Solar Pond
• Partitioned Salt-stabilized
Pond

15. Conclusion of Solar Pond
 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.
 This is very alternative and useful way for future to produce enery .

16. Thank you