Name__________________
BUILD A SOLAR OVEN LAB
Solar ovens use solar energy—light and heat emitted from the
sun—to cook food. They can also be used
Objective:
to pasteurize water or even sterilize
To design, construct, and test a instruments. How does a solar oven
device that either minimizes or work? The simple answer is that it is
maximizes thermal energy designed to absorb more heat than it
transfer. releases.
Challenge:
The mission is to build a solar oven and test it out to see if it works well enough to make S’mores! Materials: General building supplies
Thermometer
Timers
Cardboard box
Aluminum Foil
Black construction paper
Clear plastic
Tape
Newspaper
Sunshine OR gooseneck lamp with 100W bulb
S’mores fixin’s (graham crackers, marshmallows, and chocolate)
The solar oven you will build in this
activity is a relatively simple one made
out of a pizza box, aluminum foil, plastic
wrap and a sheet of black paper. You will
cut a flap out of the pizza box's lid and
line this flap with aluminum foil. This will
reflect sunlight into the box. You'll also
seal the opening with plastic wrap. This
plastic "window" works like a greenhouse
roof, allowing (direct and reflected)
sunlight to pass into the box, while also
retaining heat. At the bottom of the box,
you will place black paper. This will act as
a heat sink that absorbs direct and
reflected sunlight to warm it, which will
heat food placed on top of it. This activity
also includes instructions for making a
tasty s'mores treat that you can heat up in
your own solar oven!
Review:
1.
What type of energy do solar ovens use?
2.
What energy transformation takes place in a solar oven?
3.
Why do you put black paper in the bottom of the solar oven?
View: National Geographic Solar Cooking Video and then answer these questions:
1.
Why is solar cooking important to developing countries?
2.
What is the goal of the group Solar Cookers International?
3.
What health problems have been linked to cooking indoors?
4.
How much does the solar oven cost?
5.
When using a solar oven, what is the light energy transformed into?
6.
Besides cooking what can the solar ovens be used for?
7.
How hot does the water need to be heated to be safe to drink?
Experimental Design Step 1
The student should place the construction paper on top of the box and trace the outline. Then cut three slits, leaving the edge closest to the box opening. Step 2
Form a flap by gently folding back along the uncut line to form a crease (Diagram 2). Cut a piece of aluminum foil to fit on the inside of the flap. Smooth out any wrinkles. Step 3
Measure a piece of plastic to fit over the opening you created by forming the flap in your pizza box. The plastic should be cut larger than the opening so that it can be taped to the underside of the flap. Step 4
Measure a 2nd piece of saran wrap. Tape this piece to the topside of the box. (This will make a total of two layers of saran wrap with a small layer of air in between). It is important to get these seals tight!
Step 5
Cut another piece of aluminum foil to line the bottom of the pizza box and carefully glue into place. Cover the aluminum foil with a piece of black construction paper and tape into place (Diagram 3). Note: the layer of aluminum foil underneath the black is optional. Step 6
Line the sides of the pizza box with rolled newspaper for added insulation.
Step 7
Close the pizza box top (window), and prop open the flap of the box with a wooden dowel, straw, or other device and face towards the sun (Diagram 4). Adjust until the aluminum reflects the maximum sunlight through the window into the oven interior. Step 8 Cook some s’mores!!!!
Experiment & Record
1. Record the starting temperature of the oven: _________ 2. Place the S’mores in the oven. Close the lid and begin cooking. 3. Record the temperature change in the table below. Record any observations of your food while it is cooking. SOLAR OVEN DATA RECORDINGS
Time
Min:Sec
0:00
Oven Temp.
Time Min:Sec
5:30
Oven Temp.
Time Min:Sec
1:00
S’more
0:30
6:00
2:00
1:00
6:30
3:00
1:30
7:00
4:00
2:00
7:30
5:00
2:30
8:00
6:00
3:00
8:30
7:00
3:30
9:00
8:00
4:00
9:30
9:00
4:30
10:00
10:00
5:00
10:30
11:00
Conclusion 1. What is the purpose of the newspaper in your solar oven design?
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2. Why do we use black construction paper in the interior of the oven?
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3. Where does the heat come from to cook the S’mores?
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4. Can you tell if the oven is getting hotter by looking at the S’more?
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5. What type of energy transformations took place in order to cook the S’more?
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6. What other foods could you cook in a solar oven? ________________________________________________________________
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