CooKit
Panel solar cookers are the first solar cookers
that are truly affordable to the world’s neediest. In 1994, a volunteer group
of engineers and solar cooks associated with Solar Cookers International developed
and produced the CooKit, based on a design by French scientist Roger
Bernard. Elegant and deceptively simple looking, it is an affordable,
effective and convenient solar cooker. It requires a dark, covered pot and one
plastic bag per day or one high-temperature plastic bag per month. With a few
hours of sunshine, the CooKit makes tasty meals for 5-6 people at gentle
temperatures, cooking food and preserving nutrients without burning or drying
out. Larger families use two or more cookers. The CooKit weighs half a
kilogram, folds to the size of a big book for easy transport. CooKits are now
produced independently in 25 countries from a wide variety of materials at a
wholesale cost of $3 - $7 US. We expect that the new hand-assembled CooKits
will outlast the manufactured CooKits which last for two years. Note that you
can either build your own CooKit using the plans below or you can order a
pre-built Cookit from Solar Cookers International. Your purchase helps
support SCI's work around the world.
|
Contents [hide] |
CooKits complement other cooking methods needed at
night and on cloudy days. Coming about twenty years after the first efforts to
replace open fires with improved cooking stoves, the CooKit uses no fuel at
all. The CooKit is both user-friendly and environmentally friendly. Families
can save scarce, expensive fuel for when they cannot solar cook and when
economically capable, add other, higher cost cooking improvements such as
modern biomass, smoke hoods, biogas, or liquefied petroleum gas.
The
CooKit folds to be about the size of a large notebook when not in use.
The value of
CooKits is outlined in the following manner:
Addressing fuelwood scarcities:
Solar cooking one meal a day, three
times a week has been proven to reduce fuelwood consumption and related smoke
by one third.
The CooKit saves more than four times
its value in fuelwood each year. With careful use and storage, a CooKit can be
used for two years, reducing fuelwood consumption by two tonnes.
Improving health:
The CooKit can pasteurize household
drinking water, making it safe to drink.
The solar cooking process is smokeless,
reducing respiratory diseases and eye irritation
Solar cooked foods retain vitamins,
nutrients and their natural flavors; there is no smoky taste; the foods cook
slowly in their own juices. Nutritious, slow-cooking traditional foods (beans,
root crops, and some grains) are restored to the family diet
Clean up is easy as the food never
burns or sticks to the cooking pot.
Solar cooks frequently report that the
money they save on cooking fuel purchases is used to for many essentials, such
as extra food, school supplies, and medical care.
Without having to gather wood or dung,
breathe smoke, and tend a fire – all associated with traditional cooking –
solar cooking is easy and safe for people with AIDS and other illnesses, the
elderly, disabled and young orphans.
Tying
down a CooKit solar panel cooker so that it can withstand the winds at the Iridimi Refugee Camp where over 5000 CooKits
are in use
Enhancing household and women’s
economic status:
The CooKit represents a new opportunity
for women to capitalize on an underserved market and better meet their own
cooking energy needs
Solar cooking saves time as there is
less need to tend a fire or collect firewood. A person can cook while at work,
at the market, or tending crops. Young girls can attend school instead of
searching for fuelwood.
Solar energy is free and abundant in
many areas of
Co-developers are Roger
Bernard of France and Barbara
Kerr of the USA,
with work also by Ed Pejack, Jay Campbell,
and Bev
Blum of Solar Cookers International. Extensive
field tests in the USA
and in many developing countries confirm its performance, convenience, low
cost, acceptance, and adaptability to diverse needs.
[edit] Construction plans
Plans
for making a CooKit exactly as Solar Cookers International
manufactures them. Start with a big piece of cardboard about 1m x 1.33m (3'x
4'). Cut and fold as shown. The angles and folds shown are best, but small
variations are OK.
For detailed plans, see Solar Cookers: How to Make, Use, and Enjoy.
This is a handbook published by Solar Cookers International that
includes detailed plans for build a CooKit solar panel cooker. (There are also
detailed versions in French, Arabic, and English for Kenya.)
Simple plans in other languages are available: German, Indonesian, Luo, Persian, Portuguese, Russian, Spanish
If you can't find a large flat piece of cardboard,
consider building a Fun-Panel solar cooker instead.
Hints:
To make clean straight folds in
cardboard, first make a crease along the line with a blunt edge such as a spoon
handle, then fold against a firm straight edge.
Make the slots a little too small and
narrow so that they fit snugly to hold up the front panel.
Glue aluminum foil on the side that will form the
inside surfaces when the oven is set up for cooking.
To set up, lay panel flat with shiny
side up. Fold up front and back parts and fit back corners into the slots in
front.
You're ready to cook! Put your food into a dark-colored pot.
Then place the pot inside a plastic
bag (an oven cooking bag will withstand the heat best). Close the open end
of the bag and place pot and bag into the center of the cooker.
[edit] Plastic bags and other glazings
Place a dark-colored pot with a lid inside a
plastic bag. Use an oven cooking bag alone or a normal plastic bag using a wire
frame (see below) to keep the pot from touching the bag (to avoid melting the
bag).
See main article: Glazing
[edit] Tips and Tricks
|
|
Dr. Steven
Jones found that raising the pot on a wire frame improved cooking in a
panel cooker. |
|
|
Wietske Jongbloed created a simple frame to
allow the use of normal plastic bags (instead of heat-resistant oven cooking bags). |
|
|
Jose
Albano created this frame to protect normal plastic bags (photo shows
frame with bag removed). |
|
|
Dr. Ashok Kundapur has suggested a way to make a
housing out of flat plastic sheeting. A bottom cylinder is supported by wire
frame while a transparent cover, made of the same plastic material, makes
access to the food very easy. This arrangement can also be used for retained-heat cooking. |
|
|
Stephen Harrigan found that discarded plastic
phone cards, which are readily available in |
|
|
To remedy
the moisture problem inherant in a product made of cardboard, the Solar Cookers
International East Africa Office and colleagues have added notebook
binding tape, also readily available in large cities or capitals to seal
steno notebooks for students. |
[edit] Variations
[edit] Kundapur variation
Ashok
Kundapur has designed this version of the CooKit that is easier mark and
cut out of a single sheet of cardboard. 
[edit] Manos Unidas variation
Solar Cookers International's standard
CooKit calls for a lot of curves, which can be hard to make with a hand held
blade. Juan Urrutia Sanz of the Manos Unidas
organization in Spain
writes that his group promotes a variation on the CooKit shape that is easier
for many people to make at home. The Manos Unidas version, called Cocinsol II.
Señor Urrutia y Sanz reports that it cooks as well as the CooKit and actually
has more reflective surface area. SCI's Jay Campbell
agrees. Jay is an engineer who has chaired the SCI Research Committee and who
worked on engineering the CooKit for manufacture in Kenya. (One key
advantage of the CooKit's curved shape is that it is easier to figure out a way
to fold it into an album-sized package for easy storage and transport.) To make
your own Cocinsol II, use the shape and dimensions shown in the graphic.
Cardboard is an inexpensive material to use which holds its shape and is also
easy to fold. However, woven mats or baskets, molded plastics or wood can be used.
The solid lines in the design show where to cut; the dotted lines show where to
fold. Cover the surfaces of one side with shiny material such as aluminum foil
or shiny gift wrap (which will reflect light to the pot at the center of the
cooker).
[edit] Diassana variation
Figure
1
Mr. Gnibouwa Diassana, of
Figure
2
Mr. Diassana also applies creative thinking to
obtain low-cost materials. He notes that tea, a very popular beverage in
What is lacking in Bla, however, are large pieces
of cardboard. To adapt to this problem, Mr. Diassana makes solar CooKits from
five pieces of cardboard (see figure 1), which he patches together using small
thin pieces of cardboard or pieces of satin fabric (glued or sewn into place to
hold the large CooKit parts together, see figure 2).
[edit] King variation
Detailed
plan for building a CooKit of any size by using an arbitrary unit of measure
Philip
King writes of his variation:
I've made one CooKit and wanted to make more, but
each time I've looked at the published plans I've found that they don't suit my
way of thinking. I also find them difficult to scale to suit an arbitrary size
of material. So, and in case there are others like me who get dizzy looking at
all those angles and inches and centimetres, I've drawn my own design with the
following intentions:
to use as few measurements as possible
to use an arbitrary unit
to find all angles automatically
to use straight-line cuts throughout
to use as few cuts as possible (I could
still lose a few)
to derive details easily without a
template
to eliminate guesswork or fudging
to reduce the need for written
instructions
I also wanted it to be as close as possible to
SCI's classic and well-proven CooKit design but have some distinctive features
of its own.
Of course, the production-line cookers are quite
quickly made using templates, so this new plan has no advantage there. It is
really intended to help those who are making a one-off cooker out of whatever
randomly-sized material they happen to get hold of.
A
completed CooKit made with this design variation
The design
which follows is really meant for heavy corrugated board and not intended to
fold to a small size (that's not to say it wouldn't if thin enough, I just
haven't worked out yet how to derive the folds) and although the back angles
are pretty close to the classic design they are different to a couple of
degrees. The front panel is deeper and the back lower than in the classic, but
not by much.
The chevron cuts in the ends of the side wings are
to retain some surface area while also making the tabs narrower to fit the
slots. I had an earlier design with a wider base and front panel to accommodate
longer slots, but I like this one better, even though it adds a couple of cuts.
The chevrons also satisfy my desire for a distinctive feature. The snips off
the corners of the wings are to help with very stiff material when fitting the
points into the slots; they don't really have to be measured, just a bit
snipped off.
Diagram
shows how this design compares to the standard Solar Cookers International
design.
The basic unit is the orange block, and a unit size
of 1.5 inches gives a sheet size of 48" x 36". Clearly, a unit size
of 1" makes a sheet size of 32" x 24". Working in metric, a unit
size of 4 cm yields a sheet size of 128 cm x 96 cm, which is about five per
cent larger than the 48" x 36" sheet.
I have also made this plan available as a PDF file.
Having just made a full-sized example from this
plan I can confirm that it is fast and accurate. However, I know how it's
supposed to work, so I would welcome comments from anyone who tries to follow
this plan to build a cooker.
Exernal links
Scalable
CooKit design simplifies measurements - Solar Cooker Review
Full-resolution
PDF file showing this design - Philip
King
[edit] Plastic/mylar variation
These
CooKits are made of polypropylene flute board.
In February 2008, Stephen and Sheila Harrigan shipped 275
of these durable plastic CooKits to the Sakali Refugee Camp in
[edit] Wooden variation
This
CooKit is made of wood covered with aluminum foil.
[edit] Buying a CooKit
Order a pre-built
Cookit from Solar Cookers International. Your purchase helps support SCI's
work around the world.
CooKits can also be purchased from the Solar Cookers
International East Africa Office.