Solar Cooker
Introduction
Nowadays, popularity of
solar cooker is widespread from
Europe to Asia. Our group
wants to find out what the
structure of the solar cooker is,
and how it works, so we do a
project of solar cooker, in order
to know these things.
Material Used
Metal foil
Slide
Rope
(X2)
Black
paper
Paper
box(X2)
Inside
cotton
Coke cans：
(wrapping the water
container with the
black paper)
Application of physical principle
Sun
This design aims：
1.To absorb more sunlight from the Sun.
→ We use a rope to fix the top and the lower
lid to make sure the angle of reflection
and angle of incidence are the same.
→To ensure that sunlight can reach the
metal foil above.
2. To prevent heat loss by conduction
→Outside the box, we cover the box with
some black papers for better absorption of
heat.
→Inside the box, we use silver metal foil to
cover the box .
→we put some cotton under the aluminum
can and in the space between the inner and
outer box.
Result of the experiment (1)
Time
Temperature
Initial temperature
28 ℃
5mins later
29℃
10mins later
30℃
15mins later
30.5℃
20mins later
31℃
25mins later
32℃
30mins later
34℃
35mins later
35℃
40mins later
37℃
45mins later
39℃
50mins later
39℃
55mins later
40℃
60mins later
41℃
Improving the performance
1.We place a plastic colourless lid on the solar cooker .
→To reduce heat loss to the surroundings by convection.
→To produce a greenhouse-like environment.
2. We use thicker paper boxes to construct the body of the cooker.
→To reduce heat loss by conduction and convection.
3. We put the cotton wool in the solar cooker.
→To reduce heat loss by conduction.
4. We paste some smooth metal foil onto the inner surface of the solar
cooker.
→ the heat energy will be reflected more in our solar cooker.
5. We use a magnifying glass.
→ To focus the solar energy.
6. We wrap a piece of black paper around the water container .
Result of the experiment (2)
Time
Temperature
Initial temperature
23℃
5mins later
25℃
10mins later
26.5℃
15mins later
28℃
20mins later
30℃
25mins later
32℃
30mins later
34℃
35mins later
35.5℃
40mins later
37℃
45mins later
38℃
50mins later
40℃
55mins later
42℃
60mins later
44℃
Discussion
1. How can we use reflection to gather more solar
energy?
2. What kind of materials should be used to construct the
body of the solar cooker? Why?
3. What other measure can help to reduce heat loss by
conduction and convection?
4. How can we make use of greenhouse effect to trap
more solar energy?
5. How should the container of water look like?
6. When and how the solar cooker should be used to
enhance its performance?
Conclusion
To sum up, in making this solar cooker, we
know that there are many theories and principles
behind. For example, we learnt that black paper can
absorb more heat energy; using colourless plastic as
a covercan trap the heat inside the cooker etc.
We also have difficulties in division of jobs and
in determining the time of completion of the project.
However, we have lots of fun in the process!
Members
Chan Sau Ling (3)
Chan Wai Lan (4)
Chung Wing Yin (6)
Hui Siu Ki (7)
Hui Siu Shuen (8)
Thank you!