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1. Science - Applied Science - Renewable Energy - 7 Energy from
Ambient Heat (P9517300)
7.3 Peltier effect - Cooling machine
Experiment by: cooling
Printed: Nov 21, 2016 2:52:52 PM
interTESS (Version 12.03 B193, Export 2000)
Task
Task
Is it possible to cool down a beaker filled with water using a Peltier element?
A beaker with water is situated on the Peltier element of the thermo generator. If someone
lets current flow in this Peltier element while it is set at the correct polarity, the upper plate
of the Peltier element cools the water down.
Use the space below for your own notes.
Logged in as a teacher you will find a button below for additional information.
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2. Material
Materials
Materials in the "Pupil Kit for Renewable Energy EN1" (Order Nr. 13287.88)
QuantityOrder No.MaterialPosition No.
105770.00Thermogenerator for student experiments1
105903.00Beaker, polished2
238056.00Lab thermometer, -10... +100°C3
136011.01Beaker, 100 ml, low form, plastic4
124025.00Stopwatch, 24h, 1/100 s & 1s5
107360.04Connection cord, 32 A, 250 mm, blue6
107360.01Connection cord, 32 A, 250 mm, red7
107264.00Double socket, 1 pair, red and black8
Additional Material
113505.93Power supply 0...12 V DC / 6V , 12 V AC9
Water
Materials needed for the experiment
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3. - 3 -

4. Setup
Setup
Fasten the Peltier element to the aluminium block with the help of the yellow clip (fig. 1). Be
sure to place the Peltier element in such a way that its smaller side is on top.
Fig. 1
Connect the thermo generator to the power supply with the help of both double sockets and
the connection cords (fig. 2). The power supply is switched off. Make sure that the red
connection cord of the thermo generator is connected to the negative pole of the power supply
unit (blue socket) and the black connection cord is connected to the positive pole (red socket).
Fig. 2
Turn the current regulator to 1A and the voltage regulator to the stop position (fig. 3).
Fig. 3
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5. On one side of the aluminium block there is an opening for the temperature measurement
(fig. 4).
Fig. 4
Insert one of the two thermometers in this opening. Make sure that the measuring tip of the
thermometer touches the aluminium block (fig. 5).
Fig. 5
In order to prevent the thermometer from slipping out of the opening during the experiment,
you can put the other end of the thermometer, for instance, on the cover in which it is kept in
the box (fig. 7).
Fig. 6
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6. Measure 30ml cold tap water using the small beaker and fill the water in the polished beaker.
Then place the beaker on the Peltier element (fig. 7).
Fig. 7
Now dip the second thermometer in the water (fig. 8).
Fig. 8
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7. Action
Procedure
Measure the temperature ϑ1 of the water and the temperature ϑ2 of the aluminium block (at
the time t = 0) and write them down. Switch on the power supply and write down the
temperatures ϑ1 and ϑ2 at the times t = 1, 2, 3, 4, 5 in table 1 (fig. 9).
Fig. 9
Switch off the power supply, pour the water out of the beaker and place the Peltier element
on the table. Wait until the aluminium block has cooled down again.
Afterwards, repeat the measurement using a current of 0.5A and write down the measured
values under table 2.
Switch off the power supply, pour the water out from the beaker and place the Peltier element
on the table. Interchange the connection cords in the power supply unit (fig. 10).
Fig. 10
Take the Peltier element in your hand. Switch on the mains appliance and observe the
temperatures in the Peltier element (fig. 11). Take down your observations in (1).
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8. Fig. 11
Switch off the power supply again.
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9. Results
Results
Table 1
Measurement with a current 1A
ϑ2 in °Cϑ1 in °Ct in min
nnnnnnnnnnnnnnnnnnnn0
nnnnnnnnnnnnnnnnnnnn1
nnnnnnnnnnnnnnnnnnnn2
nnnnnnnnnnnnnnnnnnnn3
nnnnnnnnnnnnnnnnnnnn4
nnnnnnnnnnnnnnnnnnnn5
Typical Results
Measurement with a current 1A
ϑ2 in °Cϑ1 in °Ct in min
22,022,00
23,020,51
25,018,52
27,017,03
28,516,54
29,516,05
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10. Table 2
Measurement with a current 0,5A
ϑ2 in °Cϑ1 in °Ct in min
nnnnnnnnnnnnnnnnnnnn0
nnnnnnnnnnnnnnnnnnnn1
nnnnnnnnnnnnnnnnnnnn2
nnnnnnnnnnnnnnnnnnnn3
nnnnnnnnnnnnnnnnnnnn4
nnnnnnnnnnnnnnnnnnnn5
Typical Results
Measurement with a current 0,5A
ϑ2 in °Cϑ1 in °Ct in min
23,023,00
23,522,51
24,021,52
25,020,53
25,520,04
26,020,05
Observation of the temperature after the pole change
(1)
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11. After the change in pole, the smaller plate of the Peltier element heats up and the
bigger plate cools down.
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12. Evaluation
Evaluation
Question 1
What influence does the current flowing through the Peltier element have on the temperature
of the water and the temperature of the aluminium block?
Answer
Due to the applied voltage a current flows through the Peltier element. The water in
the beaker cools down and the aluminium block warms up.
Question 2
What is caused by changing the intensity of current from 1A to 0.5A c?
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13. Answer
When using a current intensity of 0.5A the water cools down more slowly than with
a current of 1A and the aluminium block also heats up more slowly.
Question 3
What do you observe when changing the poles of the voltage?
Answer
After changing the poles of the voltage the small plate heats up and the big plate
cools down.
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