The BYU Solar Cooker/Cooler | Page 6

(over
about an hour), readjust the position of the funnel to follow the sun's
path. During winter months, when the sun is low on the horizon (e.g.,
in North America), it is helpful to lay the funnel on its side, facing the
sun.

VI. Tests
Tests in Utah
[Image: 09.jpg --Photo description: This is a picture of the funnel
sitting tilted at an angle between two stands. The funnel has no hole at
the bottom; where there should be a hole is solid and shiny like the rest
of the funnel. A crossbeam connects the two stands, above the funnel.
Hanging by string from the crossbeam so that it rests near the shiny
bottom of the funnel is a black canning jar, surrounded by a clear
plastic bag. The bag appears to be blown up, full of air, and not
touching the jar.]
I have personally used the Solar Funnel Cooker to cook lunches over
many weeks. My favorite foods to cook are potatoes (cut into logs or
slices) and carrot slices. Vegetables cook slowly in their own juices and
taste delicious. I also make rice, melted cheese sandwiches, and even
bread in the Solar Funnel Cooker. I usually put the food out around
11:30 and let it cook until 12:45 or 1 pm, just to be sure that it has time
to cook. I've never had any food burn in this cooker.

I have also cooked food in the mountains, at an altitude of around 8,300
feet. If anything, the food cooked faster there--the sunlight filters
through less atmosphere at high altitudes.
I find that people are surprised that the sun alone can actually cook
food. And they are further pleasantly surprised at the rich flavors in the
foods which cook slowly in the sun. This inexpensive device does it!
Students at Brigham Young University have performed numerous tests
on the Solar Funnel Cooker along with other cookers. We have
consistently found much faster cooking using the Solar Funnel Cooker.
The efficiency/cost ratio is higher than any other solar cooking device
we have found to date. Mr. Hullinger also performed studies of
transmissivity, reflectivity and absorptivity of alternate materials which
could be used in the Solar Funnel Cooker. While there are better
materials (such as solar-selective absorbers), our goal has been to keep
the cost of the Solar Cooker as low as possible, while maintaining
safety as a first priority.
Tests in Bolivia
The BYU Benson Institute organized tests between the Solar Funnel
Cooker and the "old-fashioned" solar box oven. The solar box oven
cost about $70 and was made mostly of cardboard. It took nearly two
hours just to reach water pasteurization temperature. The Bolivian
report notes that "food gets cold every time the pots are taken from and
into the oven." The solar box oven failed even to cook boiled eggs.
(More expensive box cookers would hopefully work better.)
An aluminized-mylar Solar Funnel Cooker was also tested in Bolivia,
during the Bolivian winter. Water pasteurization temperature was
reached in 50 minutes, boiled eggs cooked in 70 minutes, and rice
cooked in 75 minutes. The Bolivian people were pleased by the
performance. So were we! (La Paz, Bolivia, August, 1996).
I also donated two dozen solar funnel cookers for people in Guatemala.
These were taken there by a group of doctors going there for
humanitarian service. The people there also liked the idea of cooking

with the sun's free energy! For an aluminized-Mylar Solar Funnel
Cooker kit, please contact CRM (licensed manufacturer) at +1 (801)
292-9210.
[Image: 10.jpg -- Photo description: This photo shows what looks like
the same style of funnel as in the above pictures except that it doesn't
look homemade but something produced by a factory. The photo shows
something which looks like a machined metal/shiny plastic funnel.]

VII. Water and Milk Pasteurization
Contaminated drinking water or milk kills thousands of people each
day, especially children. The Word Health Organization (WHO) reports
that 80 percent of illnesses in the world are spread through
contaminated water. Studies show that heating water to about 65
degrees to 70 degrees Celsius (150 degrees Fahrenheit) is sufficient to
kill coliform bacteria, rotaviruses, enteroviruses and even Giardia. This
is called pasteurization.
Pasteurization depends on how hot and how long water is heated. But
how do you know if the water got hot enough? You could use a
thermometer, but this would add to the cost, of course. When steam
leaves the canning jar (with lid on tight) and forms "dew" on the inside
of the cooking bag, then the water is probably pasteurized to drink.
(The goal is to heat to 160 degrees Fahrenheit for at least six minutes.)
With a stripe of black paint scraped off the jar, one can look through
the bag and into the jar and