1) A student designed two solar ovens using different materials and recorded their effectiveness by measuring temperature changes over time when placed in the sun and shade.
2) The first design used white foam and cloth and achieved a maximum temperature of 73.4°C. The second design used sand and foam but only reached a maximum of 37.4°C.
3) Based on the temperature measurements and impact scores of the materials, the first design performed better with a total score of 15 points compared to -11 points for the second design. The student reflected that sand was not an effective insulator.
2. Imagine for design
#1Idea #1
What we imagined first was use white cloth
and white foam
All together we need 3 units or less
The advantage for this idea is to use only
insulators
The disadvantage for this is that the foam is
far away from the least environmental
impact
Monday, May 20, 13
3. Imagine for design
#2
Idea #2
Our materials are two units of newspaper of
one unit of pipe insulation
Our advantage of this idea is that the pipe
insulation is thick and colored black which
attracts light from the sun
Our disadvantage is of this idea is that the
pipe insulation is second to last with hurting
the environment
Monday, May 20, 13
6. Plan for design #1
Material Units
We will use
the material
by.
White Foam
White cloth
2 units=2
sheets
Shred it
1 units=1
sheets
Shred it
Monday, May 20, 13
7. Impact score for
design for design #1
Design
#1 Reduce
Natural
or
processed
Reuse Recycle
Foam
Cloth
1 units Processed Yes No
2 units Processed No Yes
Total points 7
Monday, May 20, 13
8. Solar oven testing
in the sun
(Time) (Temperature)
0 minutes 25°c
5 minutes 58.9°c
10 minutes 65°c
15 minutes 73.4°c
20 minutes 69.4°c
25 minutes 70°c
Monday, May 20, 13
9. Solar oven In the
shade
(Time) (Temperature)
1 minute 59°c
2 minute 58.9°c
3 minute 40.3°c
4 minute 34.4°c
5 minute 32.5°c
Monday, May 20, 13
10. Create for design
#1
Our heat score is our solar oven maximum temperature
subtracted from the control oven: 73.4°c - 32.5°c = 42.9°c
Our time score is the number of minutes it took to cool
down which was 4 minutes
Our total impact score was 7 points
Our total score for the solar oven is 15 points
Monday, May 20, 13
11. Improve for
design#1
The total score for our first solar
oven was 15 points
The parts of our solar oven design
that worked well were the inside
because we were near the shade
We will improve our heat score by
using better insulates
Monday, May 20, 13
18. Create for design
#2
Our heat score is our solar oven
maximum temperature subtracted from
the control oven:37-53=16
Our time score is the number of
minutes it took to cool down which
was 10 minutes
Our total impact score was 5 points
Our new total score for the solar oven
is -11
Monday, May 20, 13
19. Reflection
Our improved design did not work well because
the sand did was not a good insulator. The
materials we changed were cloth because we
thought the sand would absorb the sunlight. The
material sand was a poor insulator because it did
not hold enough heat because our temperature
decreased.
If we could improve again, we would go back with
our first design because they were good insulators.
We could also place our shredded materials
differently so that the heat does not go out the
holes.
Monday, May 20, 13
