The document presents information on a final year project presentation about solar ponds. It discusses that solar ponds are large-scale energy collectors that can store thermal energy through natural convection. They work by creating three distinct layers - an upper convective zone, intermediate non-convective zone, and lower convective zone, with increasing salt concentrations at lower depths. This salinity gradient prevents convection and efficiently stores solar energy for applications such as water desalination and power generation. The presentation covers the working principles, advantages, applications and conclusions about solar ponds.

1. FINAL YEAR PROJECT
PRESENTATION ON
SOLAR POND
SUBMITTED BY:- GUIDED BY:-
1.AMAN KUMAR(14UME019) DR. T.N VERMA
2.BIJAY SHANKER PANDEY(14UME020)
3.PRASHANT JEET(14UME021)
DATE-15-11-17 NIT MANIPUR

2. 

INTRODUCTION
WHAT IS A SOLAR POND
WHAT IS NATURAL RESERVOIR &
THEIR MECHANISM
WORKING PRINCIPLE
-

ADVANTAGES
CONCLUSION
REFERENCES
DATE-15-11-17 NIT MANIPUR
CONTENT

3. • The sun is the largest source of renewable energy and this energy is
abundantly available in all parts of the earth. It is in fact one of the best
alternatives to the non-renewable sources of energy .
• Solar energy has been used since prehistoric times, but in a most
primitive manner. Before 1970, some research and development was
carried out in a few countries to exploit solar energy more efficiently, but
most of this work remained mainly academic.
• One way to tap solar energy is through the use of solar ponds. Solar
ponds are large-scale energy collectors with integral heat storage for
supplying thermal energy. It can be use for various applications, such as
process heating, water desalination, refrigeration, drying and power
generation .
DATE-15-11-17 NIT MANIPUR
INTRODUCTION

4.  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. Once it reaches the surface, the water loses its heat to the
air through convection, or evaporates, taking heat with it. The
colder water, which is heavier, moves down to replace the warm
water,creating a natural convective circulation that mixes the water
and dissipates the heat.The design
convection or evaporation in order
the pond.
of
to
solar
store
ponds reduces either
the heat collected by
 A solar pond can store heat much
more efficiently than the body of
water of same size because the
salinity prevent convectional current
DATE-15-11-17. NIT MANIPUR
WHAT IS SOLAR POND....?

5. When solar radiation is concentrated on bottom layer of
reservoir it heats the water molecules and subsequently
density of same decreases due to which it goes up and heat
transfer takes place on the top layer with surrounding air
and the cycle goes on….
Here energy absorbed is lost.
Problem associated here….
how to conserve the lost energy.
DATE-15-11-17 NIT MANIPUR
NATURAL RESERVIOUR

7. BASIC EQUATION

8.  The solar pond normally consists of following three zones :-
1) Upper convective zone(UCZ) :- Adjacent to the surface there is
ahomogeneous convective zone that serves as a buffer zone
between environmental fluctuations at the surface and conductive
heat transport from the layer below.
WORKING PRINCIPLE

9. 2) Intermediate gradient zone:- A gradient which serves as the non-
convective zone which is much thicker and occupies more than half the
depth of the pond. Salt concentration and temperature increase with depth.
3) Lower convective zone(LCZ):- This is the highest salt concentration zone
and where the high temperature are built up. Almost as thick as the middle
non-convective zone.
 To maintain a solar pond in this non-equilibrium stationary state, it is
necessary to replace the amount of salt that is transported by molecular
diffusion from the LCZ to the UCZ. This means that salt must be added to
the LCZ, and fresh water to the UCZ whilst brine is removed.
 The surface area of the pond affects the amount of solar energy it can
collect.The dark surface at the bottom of the pond increases the absorption
of solar radiation. Salts like magnesium chloride, sodium chloride or sodium
nitrate are dissolved in the water, the concentration being densest at the
bottom (20% to 30%) and gradually decreasing to almost zero at the top

10. ADVANTAGE
 Environment friendly energy –
no pollution!
 Reliable energy source.
 Stores heat, so it can be used
24*7*365.
 Can be constructed according
to requirements.
 Low maintenance costs.
DISADVANTAGE
 Low efficiency
 Space availability
 Salt and water supply
needed
 Low efficiency due to:Heat
losses.

11. APPLICATION
 Salt production (for enhanced evaporation or purification of salt, that is
 production of ‘vacuum quality’ salt)
 Aquaculture, using saline or fresh water (to grow, for example, fish or brine
shrimp)
 Dairy industry (for example, to preheat feed water to boilers)
 Fruit and vegetable canning industry
 Fruit and vegetable drying
 Grain industry (for grain drying)
 Water supply (for desalination) .
DATE-15-11-17 NITMANIPUR

12. • Renewable energy magazine , 2013,vol 1
• Nptel lecture on conventional energy
• G.r.r murthy and k.p pandey , solar ponds:a perspective from Indian agriculture
, department of agricultural and food engineering , Indian institute of
technology , kharagpur, india,200.
• Figures from google source
DATE-15-11-17 NIT MANIPUR
REFERENCE

13. Thank you…