International Journal of Advancements in Research & Technology, Volume 2, Issue 6, June-2013
ISSN 2278-7763
111
Photovoltaic Driven Dual Purpose Thermoelectric Refrigerator
for Rural India
Surith Nivas M1, Vishnu Vardhan D2, Raam kumar PH3, Sai Prasad S4 , Ramya.K5
1, 2, 3, 4&5
Department of Electrical and Electronics Engineering, RMK Engineering College, Chennai, India.
Email: surithnivas97@hotmail.com, vishnuvardhaneee@hotmail.com, raamkumarph@gmail.com, ssaiprasadeee@yahoo.com,
jce.ramya@gmail.com
ABSTRACT
This paper outlines the implementation of photovoltaic driven refrigerator cum heating system powered from solar panels
with a battery bank. Different from conventional refrigeration systems, thermoelectric refrigeration, based on the Peltier
effect, does not require any compressor, expansion valves, absorbers, condensers or solution pumps. Moreover, it does not
require working fluids or any moving parts, which is friendly to the environment and results in an increase in reliability. It
simply uses electrons rather than refrigerants as a heat carrier. Nowadays, thermoelectric refrigeration devices have a distinct
place in medical applications, electronic applications, scientific equipment and other applications, where a high-precision
temperature- -control is essential We demonstrate a Novel, Refrigeration cum Heater utilizing 3 Thermoelectric (Te) modules
mounted around a load cabinet. The Performance of this model is Experimentally Evaluated with an Aluminium cabinet.
The device is powered by a Non-conventional energy resource, here PV Cells. The cabinet can attain a temperature of about
8°C(min) till 200°C(max).The difference between the existing methods and this model, is that a thermoelectric cooling system refrigerates without use of mechanical devices(Conventional Condenser fins and Compressor) and without refrigerant
too. Since the Peltier module is compact in size, a refrigeration or heating system can be designed according to the user’s
requirements (in desired size and shape).
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Keywords : Photovoltaic system, thermoelectric refrigeration, peltier module, solar heater
1 INTRODUCTION
A
developed model of commercial thermoelectric
refrigertors with finned heat exchanger is established. The aim
of this chapter is to present some fundamental aspects of the
direct thermoelectric conversion. Thermoelectric systems are
solid-state heat devices that either convert heat directly into
electricity or transform electric power into thermal power for
heating or cooling. Such devices are based on thermoelectric
effects involving interactions between the flow of heat and
electricity through solid bodies. These phenomena, called Seebeck effect and Peltier effect, can be used to generate electric
power and heating or cooling. Solar energy is the most low
cost, competition free, universal source of energy as sunshine's
throughout. This energy can be converted into useful electrical
energy using photovoltaic technology .The steady state reduction of price per peak watt and simplicity with which the installed power can be increased by adding panels are attractive
features of PV technology.
Thermoelectric refrigeration replaces the three main working parts with: a cold junction, a heat sink and a DC power
source. The refrigerant in both liquid and vapor form is replaced by two dissimilar conductors. The cold junction (evaporator surface) becomes cold through absorption of energy by
the electrons as they pass from one semiconductor to another,
Copyright © 2013 SciResPub.
instead of energy absorption by the refrigerant as it changes
from liquid to vapor. The compressor is replaced by a DC
power source which pumps the electrons from one semiconductor to another. A heat sink replaces the conventional condenser fins, discharging the accumulated heat energy from the
system. The difference between two refrigeration methods,
then, is that a thermoelectric cooling system refrigerates without use of mechanical devices, except perhaps in the auxiliary
sense, and without refrigerant.
.
Fig 1 Block Diagram
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International Journal of Advancements in Research & Technology, Volume 2, Issue 6, June-2013
ISSN 2278-7763
Hardware Requirements:








Thermoelectric module (Tec1-12703HT)
PIC Microcontroller (16F877A)
Temperature sensor (LM35Dz)
Power storage battery (12v,7.2Ah)
Solar panel (12v,5w,750mA)
Relay (10A,24VDC)
Relay driver (ULN2003)
LCD
112
called "carriers" and they are the agents that move the heat
energy from the cold to the hot junction. Heat absorbed at the
cold junction is pumped to the hot junction at a rate proportional to carrier current passing through the circuit and the
number of couple. Good thermoelectric semiconductor materials such as bismuth telluride greatly impede conventional
heat conduction from hot to cold areas, yet provide an easy
flow for the carriers. In addition, these materials have carriers
with a capacity for transferring more heat.
2 PRINCIPLE OF SOLAR POWER GENERATION
The principle of power generation behind the solar cells consists of the utilization of the photovoltaic effect of semiconductors. When such a cell is exposed to light, electron-hole pairs
are generated in proportion to the intensity of the light. Solar
cells are made by bonding together p-type and n-type semiconductors. The negatively charged electrons move to the ntype semiconductor while the positively charged holes move
to the p-type semiconductor. They collect at both electrodes to
form a potential. When the two electrodes are connected by a
wire, a current flows and the electric power thus generated
can be transferred to an outside application.
Fig 3 Dimensions of Peltier module
Sno
1.
Item
Input voltage max.
Symbol
Vmax
Parameter
15.4V
2.
Max. current
Imax
3.3A
3.
Max. heating temperature
Tmax
200°C
4.
Min. cooling temperature
Tmin
6°C
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Fig 4 Specifications Of Peltier Module
The high performance of the thermoelectric coolers, produced
allows us to increase the rate of cooling and reach a larger
temperature difference in relation to the environment. Thermoelectric coolers are optimized for source voltage 12V and
perform high cooling as well heating at low power consumption
4 PIC MICRO CONTROLLER (16F877A)
Fig 2 Principle Of PV Cell
PIC microcontroller is used to monitor heating and cooling
inside the cabinet. It also controls the relay driver to change
the mode(Heating mode or Cooling mode).
3 THERMOELECTRIC MODULE
Heat absorbed at the cold junction is pumped to the hot junction at a rate proportional to carrier current passing through
the circuit and the number of couple. The semiconductor materials are N and P type, and are so named because either they
have more electrons than necessary to complete a perfect molecular lattice structure (N-type) or not enough electrons to
complete a lattice structure (P-type). The extra electrons in the
N-type material and the holes left in the P-type material are
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Fig 5 Crystal Oscillator Circuit
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International Journal of Advancements in Research & Technology, Volume 2, Issue 6, June-2013
ISSN 2278-7763
The above circuit is the crystal oscillator that supplies frequency to trigger the logic gates in microcontroller. The microcontroller we use here has only 35 single-word instructions to
learn .All single-cycle instructions except for program branches, which are two-cycle. Operating speed: DC – 20 MHz clock
input DC 200ns instruction cycle. It has 10-bit, up to 8-channel
Analog-to-Digital Converter (A/D). it has Analog Comparator
module with - Two analog comparators Programmable onchip voltage reference (VREF) module Programmable input
multiplexing from device inputs and internal voltage reference, Comparator outputs are externally accessible. Special
features of this include 100,000 erase/write cycle Enhanced
Flash program memory typical, 1,000,000 erase/write cycle
Data EPROM memory typical, Data EEPROM Retention > 40
years, Self-reprogrammable under software control, In-Circuit
Serial Programming™ (ICSP™) via two pins, Single-supply 5V
In-Circuit Serial Programmingcomplete cycle, otherwise conduction will overlap. It also has CMOS technologies that includes following features of Low-power, high-speed
Flash/EEPROM technology, Fully static design, Wide operating voltage range (2.0V to 5.5V), Commercial and Industrial
temperature ranges, Low-power consumption.
113
ture range, while the LM35C is rated for a −40° to +110°C
range (−10° with improved accuracy). The LM35 series is
available packaged in hermetic TO-46 transistor packages,
while the LM35C, LM35CA, and LM35D are also available in
the plastic TO-92 transistor package. The LM35D is also available in an 8-lead surface mount small outline package and a
plastic TO-220 package.
6 RELAY (10A, 24VDC)
Here Relay is used to reverse the supply to change the mode
i.e. to switch form cooling processes to heating vice versa. RW
Series Relay covers switching capacity by 10A in spite of miniature size to comply with user’s wide selection. RWH is approved C-UL & TÜV safety standard. The employment of
suitable plastic materials is applied under high temperature
condition and various chemical solutions. Complete protective
construction is designed form dust and soldering flux. If required, plastic sealed type is available for washing procedure.
12A at 120VAC for RW & 12A at 240VAC for RWH are UL approved. It is used for Domestic Appliances, Office Machines,
Audio Equipment, Coffee-Pots, Control units, etc.
5 LM35 PRECISION CENTIGRADE TEMPERATURE
SENSORS
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In this system the temperature prevailing inside the aluminium cabinet is measured using LM35DZ sensor whose output
is given to microcontroller to interpret it into Celsius values.
Its general description includes the LM35 series are precision
integrated-circuit temperature sensors, whose output voltage
is linearly proportional to the Celsius (Centigrade) temperature. The LM35 thus has an advantage over linear temperature
sensors calibrated in ° Kelvin, as the user is not required to
subtract a large constant voltage from its output to obtain convenient Centigrade scaling. The LM35 does not require any
external calibration or trimming to provide typical accuracies
of ±1⁄4°C at room temperature and ±3⁄4°C over a full −55 to
+150°C temperature range. Low cost is assured by trimming
and calibration at the wafer level. The LM35’s low output impedance, linear output, and precise inherent calibration make
interfacing to readout or control circuitry especially easy. It
can be used with single power supplies, or with plus and minus supplies. As it draws only 60 μA from its supply, it has
very low self-heating, less than 0.1°C in still air.
Fig 6 LM35DZ circuit diagram
The LM35 is rated to operate over a −55° to +150°C temperaCopyright © 2013 SciResPub.
Fig 7 Relay Circuit Diagram
7 RELAY DRIVER
Here relay driver is used to drive the relay by providing 0V to
switch on relay with 5V input from micro controller and vice
versa. The ULN2003 is a monolithic high voltage and high
current Darlington transistor arrays. It consists of seven NPN
Darlington pairs that features high-voltage outputs with
common-cathode clamp diode for switching inductive loads.
The collector-current rating of a single Darlington pair is
500mA. The Darlington pairs may be paralleled for higher
current capability. Applications include relay drivers, hammer
drivers, lamp drivers, display drivers(LED gas discharge),line
drivers, and logic buffers. The ULN2003 has a 2.7kW series
base resistor for each Darlington pair for operation directly
with TTL or 5V CMOS devices.
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International Journal of Advancements in Research & Technology, Volume 2, Issue 6, June-2013
ISSN 2278-7763
114
Fig 8 Circuit Of Relay Driver ULN2003
8 LCD DISPLAY
A liquid crystal display (commonly abbreviated LCD) is a
thin, flat display device made up of any number of color or
monochrome pixels arrayed in front of a light source or reflector.
Fig 10 Circuit Diagram
which monitors cooling and heating of the cabinet. Temperature sensor-LM35 series are precision integrated-circuit temperature sensors, whose output voltage is linearly proportional to the Celsius (Centigrade) temperature is kept inside the
cabinet, whose output is given to PIC microcontroller which is
programmed to interpret the voltage into Centigrade temperature values displayed in the LCD. In the cooling mode, PIC
microcontroller allows power to the module till the temperature reaches minimum temperature and it maintains the
same(once the temperature rises from the minimum temperature it restores the supply). For heating process, the supply
given to the modules are reversed with the help of relay.
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Fig 9 Interfacing Lcd With Pic 16f877a
It is often utilized in battery-powered electronic devices because it uses very small amounts of electric power. In
this system LCD is used to display the current temperature
values in °C along with indication whether system is in cooling mode or heating mode. It receives input regarding this
information from the micro controller.
9 WORKING OF THE MODEL
The source for our refrigeration cum heater system is renewable energy resource, here PV cells, are used. The power from
the solar panel is given to two batteries (12V,7.25A). From batteries the power is delivered to peltier modules(3 nos) connected in parallel each attached to their respective heat sinks.
Once the module gets the supply, it starts functioning (either
cooling or heating according to its respective mode).
The battery also supplies DC fan +fin (Heat Sink). PIC Microcontroller receives 5V from the A.C power source i.e through
Step
down
transformer
(230V
to
12V),
Copyright © 2013 SciResPub.
Fig 11 Arial View Of The Model
Once the terminals are reversed, the heating process starts.
During heating, PIC microcontroller allows power to the
module till the temperature reaches maximum point and it
maintains the same (once the temperature falls below the maximum point the supply is restored) such that the temperature
is maintained inside the cabinet.
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International Journal of Advancements in Research & Technology, Volume 2, Issue 6, June-2013
ISSN 2278-7763
115
Table 1: Comparison Between Existing Heator And
Proposed Model
Existing
system :
Fig 12 Performance Analyses Between Existing
And Thermoelectric Model (cooling Graph)
The above graph depicts the plot of time in minutes and load
temperature in degree Celsius for thermoelectric model and
existing domestic model. From the graph, it is clear that thermoelectric model attains the minimum temperature about 8°C
in 40 minutes and maintains the same, where as the existing
model takes 1hour to attain the same. Further the thermoelectric model maintains 8°C for nearly 5hours and then it starts
decreasing as shown. where as in existing model negative
temperature is achieved after 4 hours 10 minutes of time. This
is the only disadvantage of the thermoelectric model in which
the time taken to freeze is more.
heater
Thermoelectric heater :
Cannot be operated
during power outages.
Can be operated during
power outages as power is
given from PV cells.
Induction coil is
used for heating which
consumes large amount
of power.
Heat is derived from peltier module which consumes
less power.
The cost of heating
water with electricity
can be quite large.
Electricity is not at all an
aspect here as heater works on
power obtained from PV cells
which saves maximum cost.
The system is prone
to corrosion.
Heat exchanger which is
Teflon coated is made of stainless steel and is corrosion free.
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Table 2: Comparison Between Existing Refrigeration
Model And Proposed Model
Fig 13 Performance Analyses Between Existing
And Thermoelectric Model (Heating Graph)
This graph depicts the time taken to heat cabinet from 8°C.
This is the deviation observed from domestic refrigeration
system and thermoelectric refrigeration system. Thus both
Heating & Cooling are achieved using Peltier modules and it
is experimentally evaluated.
Copyright © 2013 SciResPub.
Existing refrigeration
model
Thermoelectric
frigeration model
Emits
chlouro-fluoro
carbon. (CFC’s).
It is
Friendly.
Uses
cooling.
for
It doesn’t require refrigerant
Life span with mean
time between failures is
87,600 working hours.
Long life with mean
time between failures is
200,000 hours.
Moving parts such us
compressors, condensers are
present.
No moving parts.
refrigerant
very
re-
Eco-
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International Journal of Advancements in Research & Technology, Volume 2, Issue 6, June-2013
ISSN 2278-7763
10 TOTAL COST
Sno
Components
name
Quantity
Cost
1
Peltier module (tec112703ht)
3
Rs.2102
($12.90/pcs )
2
Solar Panel(12v,5w)
1
Rs.500
($1.8/watt )
3
PCB
1
Rs.1075
4
Battery (12v,7.2Ah)
2
Rs.1600
(2x800)
5
Relay
(ULN2003)
6
DC fan +fin
7
Relay board
8
LCD
9
PIC 16F877A
10
driver
1
3
1
Rs.20
Rs.375
(3x125)
Rs.500
116
ed. The physical dimensions and specifications of the Peltier
module are presented. It is observed that the life span of thermo electric heater cum refrigeration system is more than twice
the life span of existing conventional refrigeration or heater
system. The principle of solar panel along with its specifications and dimensions are displayed. As the future relies heavily on Non conventional energy resources, the Solar powered
thermoelectric heater cum refrigeration system will definitely
be a large aspect in terms of energy saving capacity and the
fact that the system is eco-friendly. The important aspect to be
noted is that it is an one time investment and is maintenance
free.
12 REFERENCES
[1]Taylor, R.A.; Solbrekken, G.L. "Comprehensive system-level
optimization of thermoelectric devices for electronic cooling
applications", Components and Packaging Technologies, IEEE
Transactions on, On page(s): 23 - 31 Volume: 31, Issue: 1, March
2008.
[2]Fukutani, K.; Shakouri, Ali "Design of Bulk Thermoelectric
Modules for Integrated Circuit Thermal Management", Components and Packaging Technologies, IEEE Transactions on, On
page(s): 750 - 757 Volume: 29, Issue: 4, Dec. 2006
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1
Rs.150
1
Rs.130
Transformer (235V to
12V)
1
Rs.200
11
Temperature
(LM35DZ)
1
Rs.32
12
Aluminium cabinet
1
Rs.425
sensor
Total cost
Rs.7109
11 FUTURE SCOPE
To build a real time model replacing both air conditioner
and room heater in one system, i.e Thermo Electric Hot
And Cold Room Conditioner.
12 CONCLUSION
This paper has evaluated the working of Peltier module for
producing effective heating and cooling placed inside an aluminium cabinet. By using a temperature sensor inside the cabinet surface, we get the corresponding temperature values for
each instant which are displayed in an LCD (Liquid crystal
display). The graph between temperature produced inside the
cabinet against corresponding time interval are also presented
and results are in line with the predictions. The advantages of
the thermoelectric heater cum refrigeration on comparison
with the existing heater and refrigeration system are elaboratCopyright © 2013 SciResPub.
[3]Campbell, L.A.; Wagner, R.; Simons, R.E. "Analysis and
characterization of thermoelectric module and heat exchanger
performance in a hybrid system cooling application", Semiconductor Thermal Measurement and Management Symposium
(SEMI-THERM), 2011 27th Annual IEEE, On page(s): 48 – 53
[4]Solbrekken, G.L.; Yazawa, K.; Bar-Cohen, A. "Heat driven
cooling of portable electronics using thermoelectric technology", Advanced Packaging, IEEE Transactions on, On page(s): 429
- 437 Volume: 31, Issue: 2, May 2008
[5]Sharp, Jeff; Bierschenk, Jim; Lyon, H.B. "Overview of SolidState Thermoelectric Refrigerators and Possible Applications
to On-Chip Thermal Management", Proceedings of the IEEE, On
page(s): 1602 - 1612 Volume: 94, Issue: 8, Aug. 2006
[6]Alley, Randy G. ; Soto, Marco A. ; Kwark, Leon ; Crocco,
Paul ; Koester David; “Modeling and Validation of On-Die
Cooling of Dual-Core CPU using Embedded Thermoelectric
Devices”
Semiconductor Thermal Measurement and Management
Symposium, 2008. Semi-Therm 2008. Twenty-fourth Annual
IEEE
Digital Object Identifier: 10.1109/STHERM.2008.4509370
Publication Year: 2008 , Page(s): 77 - 82
[7]Snyder, G. Jeffrey ; Soto, Marco A. ; Alley, Randy G. ; Conner, “ Hot spot cooling using embedded thermoelectric coolers” Bob Semiconductor Thermal Measurement and Management Symposium, 2006 IEEE Twenty-Second Annual IEEE
Digital Object Identifier: 10.1109/STHERM.2006.1625219
Publication Year: 2006 , Page(s): 135 – 143
[8]Koester; david ; Venkatasubramanian, Rama ; Conner, Bob ;
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International Journal of Advancements in Research & Technology, Volume 2, Issue 6, June-2013
ISSN 2278-7763
Snyder, G. Jeffrey “Embedded thermoelectric coolers for semiconductor hot spot cooling”Thermal and Thermomechanical
Phenomena in Electronics Systems, 2006. ITHERM '06. The
Tenth Intersociety Conference on Digital Object Identifier:
10.1109/ITHERM.2006.1645384
Publication Year: 2006 , Page(s): 491 – 496
[9]Simons, Robert E. Int. Bus. Machines, Poughkeepsie, NY,
USA Chu, Richard C. Semiconductor Therma Embedded
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Mar 2000 Conference Location : San Jose, CA Print ISBN: 07803-5916-X INSPEC Accession Number: 6635951 Digital
Object Identifier : 10.1109/STHERM.2000.837055
[10]STEVENS, JAMES W. HEAT
TRANSFER AND THERMOELECTRIC
FOR A GROUND-SOURCE THERMO
DEPT. OF MECH. ENG., MISSISSIPPI STATE UNIV., MS,
USA
PAGE(S): 68 – 71 PRODUCT TYPE: CONFERENCE
PUBLICATIONS MEETING DATE : 29 AUG 1999-02 SEP 1999 ISSN :
1094-2734 PRINT ISBN: 0-7803-5451-6 INSPEC ACCESSION
NUMBER: 6644458
DIGITAL
OBJECT
IDENTIFIER:
10.1109/ICT.1999.843336
DESIGN
CONSIDERATIONS
GENERATOR
117
Raam Kumar.PH is currently pursuing his
B.E (Department of Electrical and Electronics Engineering) in RMK Engineering College, Anna University, Chennai. He is receiving central sector merit scholarship
from ministry of Human Resources(HR)
GOVERNMENT OF INDIA. His area of
interest is Applied thermal Engineering,
Transmission & Distribution. Currently he is a member in Institute of Electrical and Electronics Engineers
Sai Prasad.S is currently pursuing his B.E
(Department of Electrical and Electronics
Engineering) in RMK Engineering College,
Anna University, Chennai. His area of interest is Applied thermal Engineering, Special Electric Machines. Currently he is a
member in Institute of Electrical and Electronics Engineers.
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Surith Nivas. M is currently pursuing
his B.E (Department of Electrical and
Electronics Engineering) in RMK Engineering College, Anna University,
Chennai. He has received BEST STUDENT AMBASSADOR AWARD at
Waves’12 conducted by COLLEGE OF
ENGINEERING, GUINDY, Chennai.
His area of interest is Applied thermal Engineering, microprocessor. Currently he is a member in Institute of Electrical and
Electronics Engineers.
Vishnu Vardhan. D is currently pursuing his B.E (Department of Electrical and Electronics Engineering) in
RMK Engineering College, Anna University, Chennai.He is receiving Prime
Minister Merit scholarship for Ex servicemen wards, provided by Central
Government of India. His area of interests includes Wind Energy forecasting and analysis, Renewable Energy, Applied thermal Engineering, Special Electric Machines. Currently he is a member
in Institute of Electrical and Electronics Engineers.
Copyright © 2013 SciResPub.
Ramya.K is an assistant professor in Electrical and Electronics Engineering department,
RMK
Engineering
College,
Kavaraipettai, India. She obtained her M.E.
in Power electronics and drives from Jerusalem college of engineering ,Chennai, India. She has published 6 Technical papers
in National and International conferences proceedings. She
has 0.75 years of teaching experience. She has received
AWARD from the governor of TamilNadu, HIS EXCELLENCY
THIRU.SURJIT SINGH BARNALA for her UG Project in the
year 2010 through AIMO. She also received swamykannu best
project award for her PG project in the year 2012. She topped
Anna University Rank 1 in her PG. Her research interest includes areas of resonant converters, induction motor drives
and renewable sources. Ms K. Ramya is a member of Institute
of Electrical and Electronics Engineers.
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