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Green Science SOLARENERGIE Mode D'emploi page 10

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(. SOLAR OVEN
SAFETY WARNING
1. In strong sunshine, with the Sun overhead, the solar oven model could reach 100°C (212°F)
or higher. Always handle the oven with an oven glove when it has been in the sunshine. Adult
supervision is required.
2. Use the model only as described in the instructions. The model is designed for experimental
demonstration only. It is not a cooking device. Do not eat the food heated or cooked inside as it
may not be thoroughly cooked.
BUILDING YOUR SOLAR OVEN
You will need: cardboard box, 4 x silver reflector cards, small and large squares of black paper,
transparent plastic cover sheet, 70°C (158°F) thermal indicator sticker and adhesive tape.
Also required but not included in the kit: an
oven thermometer (a room temperature
thermometer is not appropriate because
temperatures inside the oven may be too
high), aluminum foil, a small size zip-locked
bag, a piece of cheese or chocolate, and a
small egg.
1. Fold up the cardboard box as shown in
the diagram to form the oven body.
2. Place the small square of black paper
inside the oven bottom.
3. Place the transparent plastic cover on top
of the box opening. Make sure the cover is
centered over the hole before securing it
with the adhesive tape.
4. Insert the small tabs on each silver reflector card into
the slots in another to form a square, and insert the large
tabs into the slots in the transparent
cover. Your Solar Oven is complete.
SETTING YOU SOLAR OVEN
For the maximum heating effect,
you need to place your Solar Oven
under the midday Sun (i.e. between
10a.m. and 2p.m.) on a clear, sunny
day. As the Sun moves across the
sky during the day, You will also
need to tilt the oven so that the
sunshine shines straight into the
oven (use a stone to support one
side of the box). Turn the oven as
the Sun moves across the sky.
Remarks: if you would like to operate your Solar Oven indoors or at a school science
fair, you can use a desk lamp with a 60W incandescent light bulb as a source of heat.
Do not use an energy-efficient fluorescent lamp as it will not produce enough heat.
Adjust the lamp so that it is close to the oven opening and shining straight at it. It will
act as a simulated sun and heats up the oven. Adult supervision is required when
using a desk lamp.
EXPERIMENTS
1. Measuring the oven temperature
Stick the thermal sticker marked 70°C (158°F) onto an inside wall of the
oven so that you can still see it from the outside (do not stick it on the
black paper at the bottom as the paper's temperature is always higher
than that of the air). Put the oven in the sunshine. After a while the
indicator will change colour to pink, showing that the temperature has
Adhesive tape
risen above 70°C (158°F). You could make a record of the time this
takes on different days. Use the chart below to record your results.
Date
Time
The indicator only indicates if the temperature is over 70°C (158°F). Your Solar Oven could reach higher
temperatures in strong sunlight. If you would like to test this, you will need to use an oven thermometer
placed inside the solar oven. You can use a chart like this to record the temperature every 15 minutes as
the oven warms up.
Outside Temperature
Weather Condition
Time required to
Remarks
reach 70°C(158°F)

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