364 A Healthy Home
Cooking with sunlight
You can use the sun’s heat to cook in solar cookers. Solar cookers require
changing your regular cooking habits, and many solar cookers cook more
slowly than a fire or a stove. But by using the solar cooker when the sun shines
brightly, and using the regular household stove at night or when the weather
is cloudy, you can save fuel. Some cookers can pay for themselves in just a few
months because they reduce expenses for charcoal, gas, or firewood. Solar
cookers can also be used to disinfect water for drinking (see page 98).
Guidelines for cooking with sunlight
There are many kinds of solar cookers you can make or buy (see Resources).
All of them work in basically the same way. They:
• change sunlight to heat energy. Dark surfaces get hot in
sunlight. Food cooks best in dark, shallow, thin metal
pots with tight-fitting lids to hold in heat and moisture.
• retain heat. A clear heat trap around the dark pot lets in
sunlight and traps heat. Use a glass top,
an upside-down glass bowl, or a clear,
heat-resistant plastic bag marked HDPE.
glass top
• capture extra sunlight. Shiny surfaces
reflect extra sunlight onto the pot to
help cook food faster. Aluminum foil
mounted on cardboard provides a good,
low-cost shiny surface. Sheet metals
and metallic paints are not reflective
enough to work well.
reflectors
Important: Never look directly into the sun or at the shiny
surface of a solar cooker while it is cooking. This can damage your eyes.
When building a solar cooker, do not use materials that will melt or give off
fumes, such as styrofoam, polyvinyl, or some plastics.
How to use a solar cooker
Use a black pot with either a black or clear glass top. To help it cook faster,
cut food into small pieces and add a small amount of water. Place a blanket or
other insulation under the oven and place the oven in full sun just before and
during the hottest part of the day. Be sure that the solar collector opening faces
toward the sun. Turn the oven every 30 minutes or so to face directly into the
sun. If the sun goes behind a cloud, surround the oven with more insulation. If
the the food is hot but not cooked, finish cooking the food on a stove or fire.
Faster cooking
Slower cooking
No cooking
A Community Guide to Environmental Health 2012