The BYU Solar Cooker/Cooler | Page 5

pocket around the jar.]

IV. Final Steps
At this stage, you are ready to put food items or water into the cooking
vessel or jar, and put the lid on securely. (See instructions on food
cooking times, to follow.)

Place a wooden block in the INSIDE bottom of the cooking bag. I use a
piece of 2X4 board which is cut into a square nominally 4"X4" by
about 2" thick. Then place the cooking vessel containing the food or
water on top of the wooden block, inside the bag.
Next, gather the top of the bag in your fingers and blow air into the bag,
to inflate it. This will form a small "greenhouse" around the cooking
vessel, to trap much of the heat inside. Close off the bag with a tight
twist tie or wire. Important: the bag should not touch the sides or lid of
the cooking vessel. The bag may be called a "convection shield,"
slowing convection-cooling due to air currents.
Place the entire bag and its contents inside the funnel near the bottom
as shown in the Photographs.
Place the Solar Funnel Cooker so that it Faces the Sun
Remember: Sunlight can hurt the eyes: Please wear sunglasses when
using a Solar Cooker! The Funnel Cooker is designed so that the hot
region is deep down inside the funnel, out of harm's way.
[Image: 08.jpg -- Photo description: This is a close-up photo of a black
canning jar, sitting on top of a block of wood. The wood and the jar are
sitting on the ground, inside a clear plastic bag, which is full of air, like
a balloon and tied at the top so that the air in the bag keeps the bag
from touching the jar.]
Put the Solar Funnel Cooker in the sun pointing towards the sun, so that
it captures as much sunlight as possible. The design of the funnel
allows it to collect solar energy for about an hour without needing to be
re-positioned. For longer cooking times, readjust the position of the
funnel to follow the sun's path.
It helps to put the Solar Funnel Cooker in front of a south-facing wall
or window (in the Northern Hemisphere) to reflect additional sunlight
into the funnel. A reflective wall is most important in locations farther
from the equator and in winter. In the Southern Hemisphere, put the
Solar Funnel Cooker in front of a North-facing wall or window to

reflect additional sunlight into your cooker.

V. After Cooking
Remember that the cooking vessel will be very hot: Use cooking pads
or gloves when handling! If you are heating water in a canning jar, you
may notice that the water is boiling when the lid is first removed - it
gets very hot!
Open the plastic cooking bag by removing the twist-tie. Using gloves
or a thick cloth, lift the vessel out of the bag and place it on the ground
or table. Carefully open the vessel and check the food, to make sure it
has finished cooking. Let the hot food cool before eating.

Helpful Hints
1. Avoid leaving fingerprints and smudges on the inside surface of the
cooker. Keep the inner surface clean and shiny by wiping occasionally
with a wet towel. This will keep the Solar Funnel Cooker working at its
best.
2. If your funnel gets out-of-round, it can be put back into a circular
shape by attaching a rope or string between opposite sides which need
to be brought closer together.
3. For long-term applications, a hole in the ground will hold the Funnel
Cooker securely against winds. Bring the funnel inside or cover it
during rain storms.
4. The lids can be used over and over. We have had some trouble with
the rubber on some new canning-jar lids becoming soft and "sticky."
"Ball canning lids" do not usually have this problem. Running new lids
through very hot water before the first use seems to help. The lids can
be used over and over if they are not bent too badly when opened (pry
off lid carefully).

5. The jar can be suspended near the bottom of the funnel using fishing
line or string (etc.), instead of placing the jar on a block of wood. A
plastic bag is placed around the jar with air puffed inside, as usual, to
trap the heat. The suspension method allows sunlight to strike all
surfaces of the jar, all around, so that it heats faster and more evenly.
This suspension method is crucial for use in winter months.
6. Adjust the funnel to put as much sunlight onto the cooking jar as
possible. Look at the jar to check where the sunlight is hitting, and to
be sure the bottom is not in the shadows. For long cooking times