Solar refrigeration system
R.NO:- 36
SHALUMAN PAGARE
CONTENTS
❑ INTRODUCTION
❑ How it works
❑ Ty p e s o f s o l a r re f r i g e ra t i o n sy s te m
❑ Wo r k i n g o f s o l a r re f r i g e ra t i o n sy ste m
❑ Components use in solar refrigeration
❑ Advantage
❑ Disadvantage
❑ Application
❑ Conclusion
❑ References
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INTRODUCTION
Solar refrigeration
Solar refrigeration . Refrigerator which runs on
electricity provided by Solar Energy is known as
solar refrigeration . Solar-powered refrigerators
may be most commonly used in the future
generation. Developing the world to help
mitigate poverty and climate change.
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HOW IT WORKS
Solar-powered refrigeration system employs a PV panel, vapor
compressor, thermal storage and reservoir and electronic controls. The
process that makes the refrigeration possible is the conversion of
sunlight into DC electrical power, achieved by the PV panel.
The DC electrical power drives the compressor to circulate
refrigerant through a vapor compression refrigeration loop that extracts
heat from an insulated enclosure. This enclosure includes the thermal
reservoir and a phase change material .
This material freezes as heat is extracted from the enclosure. This
process effectively creates an "ice pack." enabling temperature
maintenance inside the enclosure in the absence of sunlight .
Proper sizing of the highly insulated cabinet, phase change thermal
storage, variable speed compressor and solar PV panel allow the
refrigerator to stay cold all year long. To optimize the conversion of
solar power into stored thermal energy, a compressor control method
fully exploits the available energy.
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TYPES OF SOLAR REFRIGERATION SYSTEMS
I T C O N S I S T S M A I N LY T W O T Y P E S
Rechargeable
it consist of a lead ion battery which
stores charge for critical condition.
Non Rechargeable
it directly runs on the solar panel.
These are classified into
three types
I. Photovoltaic operated refrigeration
cycle
II. Solar mechanical refrigeration
III. Absorption Refrigeration
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Working of solar refrigeration system
❑ Photovoltaic Operated Refrigeration Cycle
a) Photovoltaic (PV) involve the direct conversion of solar radiation to direct current (DC) electricity using
semiconducting materials .
b) In concept. the operation of a PV-powered solar refrigeration cycle is simple
c) vapour compression cycle with power input from Photovoltaic cells.
d) DC electric power output from PV runs the compressor of a conventional cycle.
❑ Solar mechanical refrigeration
a) Solar mechanical refrigeration uses a conventional vapour compression system driven by mechanical power that is
produced with a solar- driven heat power cycle .
b) The heat power cycle usually considered for this application is a Rankine cycle in which a fluid is vaporized at an
elevated pressure by heat exchange with a fluid heated by solar collectors .
c) A storage tank can be included to provide some high temperature thermal storage The vapour flows through a turbine
or piston expander to produce mechanical power
❑ Absorption Refrigeration System
• Absorption refrigeration is the least intuitive of the solar refrigeration alternatives.
• unlike the PV and solar mechanical refrigeration options ,the absorption refrigeration system is considered a "heat driven"
system that requires minimal mechanical power for the compression process.
• It replaces the energy-intensive compression in a vapor compression system with a heat activated "thermal compression
system”.
• Ammonia is working fluid .
• Minimal mechanical power input (pump instead of compressor).
• Absorption into water solution allows it to be pumped .
• Desorbed in generator (rectifier required to separate out water).
• Heat into generator provided by solar collector
• The pressurisation is achieved by dissolving the refrigerant in the absorbent, in the absorber section
• Subsequently, the solution is pumped to a high pressure with an ordinary liquid pump . In this way the refrigerant vapour
is compressed without the need of large amounts of mechanical energy that the vapour-compression air conditioning
systems demand
• This system greatly increases complexity.
C O M P O N E N T S U S E I N S O L A R R E F R I G E R AT I O N S Y S T E M
1.Photovoltaic (PV) Panels
2.Battery Bank
3.Charge Controller
4. Inverter
5. Refrigeration Unit
6. Thermal Energy Storage
7. Heat Exchangers
8. Piping and Insulation
9. Controls and Monitoring Systems
10. Supporting Structures
A DVA N TAG ES
▪ Solar energy is the main source of energy that is utilized to run solar
refrigerator.
▪ So, significant amount of electrical power is saved and it also causes less
pollution that would have been added due to the use of power produced by
the conventional power plants
▪ The solar energy is available in every part of the world and unlike fossil fuels
and nuclear power, it is a clean source of energy. Additional power from the
solar collector can also be used for the other domestic purposes
▪ The solar refrigerators can be very useful where there is nocontinuous supply
of electricity or difficult to get conventional fuel.
▪ More importantly it is renewable in nature. Conventional refrigeration systems
emit significant amount of gas which pollute the environment.
▪ As solar radiation is not available throughout the day, power production is
not uniform. Again it depends on the intensity of the beam radiation.
▪ Even in the hottest regions on earth, the average solar radiation flux
rarely exceeds 1 kWh/m2 and the maximum radiation flux over a day is
about 6 kWh/m2
▪ These are low values from the point of view of technological utilization.
So, those refrigeration systems can be used in those places where those
problems are not present
▪ To produce sufficient energy from solar system, it needs bigger collector
▪ So, there is a need of bigger space for the collector which is another
major problem for using solar refrigeration system
▪ Initial investment to develop such set up is also large.
A P P L I C AT I O N
▪ Solar energy should be given a chance if we want to
protect the environment
▪ We own it to our children, our grandchildren and the
generations to come .
▪ Refrigerators
▪ Freezers
▪ Ice-makers
▪ Coolers
▪ Building air-cooling systems
CO N C LU S I O N
COP for solar refrigeration systems is low, Better metrics, size, cost , Complexity of solar refrigeration systems requires more
size, bulkiness Low operating costs do not outweigh high initial investment, Advantage is that they don't rely on power grid
(PV is most practical for small scale)
T H A N K YO U
