SOLAR BOX COOKER HOW TO CONSTRUCT AND USE IT?

Transcription

1 SOLAR BOX COOKER HOW TO CONSTRUCT AND USE IT? Technology For Life,

2 Pub Heated by Technology For Life, Finland SOLAR BOX COOKER HOW TO CONSTRUCT AND USE IT? Technology For Life, 1995

3 WHY TO USE A SOLAR BOX COOKER Solar cooker is a partial solution to many serious global problems. About 2000 million people, over 1/3 of world population, have daily dependence on fuelwood as a source of their cooking and heating energy. They live in the tropics, in the most favorable areas for solar energy utilization. Fuelwood collection takes many people, mostly women, several hours daily, preventing them e.g. from attending school classes. On the other hand, fuelwood cutting results in 20,000-25,000 km2 annual loss of tropical forests (UNEP). Both of these problems could be reduced by using solar cookers. Their usage also promotes important health aspects. Diseases that are spread through contaminated water cause 80% of illnesses in the world (WHO). Heating water to pasteurization temperature 62.8 C destroys disease organisms. This temperature is easily achievable with solar cookers. Acute respiratory infections (API) are the cause of death for 1/3 of the about 15 million children under 5 years of age who die in the world each year. Large majority of these take place in the developing countries as a result of polluted indoor air due to cooking in open fire inside houses without chimney and ventilation. This problem could be greatly reduced by using the smokeless solar cookers. Solar cooker also preserves many micronutrients better than traditional cookers. Box type solar cooker is an old invention: first documented usage is from late 18th century when a Swiss Nicholas de Saussure prepared food with such a tool. Broader utilization of solar cookers started as late as in the 1970's. At the moment estimated half a million cookers are in use worldwide, mostly in China and in India. About 2/3 of these are box type and 1/3 more advanced paraboloid type (in China).

4 HOW TO USE THE SOLAR BOX COOKER COOKING FOOD AND BOILING WATER WITH SOLAR BOX COOKER IS EASY AND IT SAVES WOOD

5 TURN THE SHINY REFLECTOR OF THE COOKER TOWARDS THE SUN. USE DARK POTS, IF POSSIBLE. THE BLACK POTS ARE BEST

6 * ADJUST THE COOKER SO THAT YOU GET AS MUCH SHUNSHINE AS POSSIBLE INTO THE BOX.

7 * KEEP THE GLASS WINDOW CLOSED DURING COOKING

8 * POTS GET HOT i USE POTHOLDERS!

9 * DO NOT LEAVE THE SOLAR BOX COOKER IN THE RAIN! KEEP THE SOLAR BOX COOKER IN A DRY PLACE WHEN YOU ARE NOT COOKING.

10 COOKING WITH THE SOLAR BOX COOKER IF YOU ARE COOKING A LARGE AMOUNTS OF FOOD, IT WILL COOK MORE QUICKLY IF DISTRIBUTED BETWEEN TWO OR THREE SMALLER POTS INSTEAD OF ONE LARGE POT. SEVERALL SMALL, UNCOVERED BOWLS MAY BE PLACED INSIDE A LARGE COVERED POTTO COOK. LEFTOVERS ARE EASILY REHEATED IN THE SOLAR BOX COOKER. LIQUIDS FROM MEATS SUCH AS CHICKEN MAY BE USED FOR MAKING SOUP, COOKING RICE, OR MAKING GRAVY.

11 TIPS USING THE SOLAR BOX COOKER Use dark covered pots or pans with tigth fitting lids. You do not need to stir food while cooking. However, it's OK to check the food if you quickly replace the lid. To keep the food hot after the sun goes down, add several briks or heavy stones when you begin cooking. To maximize heat retention, lower the reflective lid onto the glass, and cover the solar box cooker with a blanket. To bake cakes or bread, preheat the cooker for at least 1/2 hour before adding the food. Preheating the owen with several briks or pieces of tile inside will also provide a source of heat.

12 HOW DOES A SOLAR BOX COOKER WORK? Box cooker is the simplest and the cheapest solar cooker type, still able to heat food to 150 degrees. It is basically an insulated box with a glass (or plastic) window, that acts as a solar energy trap by exploiting the greenhouse phenomenon. Solar radiation penetrates the window and absorbs into the walls and the bottom of the cooker and the cooking utensils (pots etc.). The darker the pots and the inside of the cooker are, the better they are heated. The window is not transparent to heat radiation so the heat radiation from the walls and the pots will be trapped inside of the cooker, heating air. To maximize the heating affect the walls and the pots should be painted black and the bottom should be covered with black metal plate to carry heat to the pots. Double window is better than a single window because it reduces heat conduct. To increase the incoming solar radiation reflective plates can be used and are required in less-than optional solar condition. They should be directed to reflect radiation from a wider area into the box. Also, the box should be designed as tight as possible to minimize hot air flow to outside.

13 MEASURES FOR 3 mm THICK CARDBOARD

14 INSULATOR SIDE BOX, 3mm CARDBOARD, 2 PIECES INSULATOR SIDE BOX, 3mm CARDBOARD, 2 PIECES INSULATOR BOTTOM BOX, 3 mm CARDBOARD THE BOXES ARE TO BE FILLED WITH INSULATING MATERIAL, E.G. WOOD CHIPS GRASS DRY MOSS NEWSPAPER

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16 MEASURES FOR 3mm THICK CARDBOARD

17 7. BLACK METAL PLATE

18 REFLECTING FOIL GLASS (OR PLASTIC) PLATE. GLUED ON THE BACK SIDE OF THE COVER BLACK PAINTED INTERIOR

19 IUFRO XX WORLD CONGRESS, CARING FOR THE FORESTS UNIVERSITY OF TAMPERE, FINLAND 6-12 AUGUST 1995 SATELLITE MEETING: 10th August 1995, 19:30-22:00 Solar cookers as a means for reducing deforestation Chair: Riitta Wahlstrom, co-chair An Lampinen, University ofjyvaskyla, Finland -- - r^^ DU\.«-Ui*V?t:^ l^ iuh CFMTRF it^ff Bu«if 43 3 U 6 B<e» Programme : Claus Montonen, University of Helsinki, Finland: Using Solar Cookers in Developing Countries, different aspects Anita Manandhar: Solar cookers as a means to reduce deforestation in Nepal. Centre for Rural Tecnology, Nepal Ulrich Oehler, Group ULOG, Switzerland: Solar cooker technology - historical perspectives and present time Artur Marques da Costa, Portugal: Experiences of using solar energy Discussion Contact: Riitta Wahlstrom, University ofjyvaskyla, Box 35, Jyvaskyla, tel , fax , or Art Lampinen, University ofjyvaskyla, Box 35, Jyvaskyla, tel , fax , ala@jyu.fi

20 6 x 15 mm WOODEN STRIPS FOR ADJUSTING SIDE REFLECTORS WIRES (0 3 mm) FOR ADJUSTING SIDE REFLECTORS (IRON)WIRE, 0 3 mm \^ 6x15 mm ^^^^^ STRIP OF WOOD ^^,^ WITH SIDE HOLES FOR^^ TILT ANGLE ADJUSTMENT \ WOODEN STRIP AND SUPPORT WIRE ON THIS SIDE, IF NEEDED

21 DIFFERENT MODELS OF SOLAR COOKERS

22 BIBLIOGRAPHY Klaus Kuhnke at al., Solar Cookers in the Third World, Friedr. Vieweg & Sohn, 1990 Pejack E (ed.), Advances in Solar Cooking, Proceedings of the First World Conference on Solar Cooking, University of the Pasific, Stockton, California, 1992 Michael Grupp, New Prospects in Solar Cooking, Synopsys, 1991 USEFUL CONTACTS Solar Cookers International, 1724 Eleventh Street Sacramento, CA95814, USA European Committee for Solar Cooker Research (ECSCR) Office of the Coordinator C/0 Synopsis Route d'olenet F Lode've, France

23 RECIPES FOR THE SOLAR BOX COOKER CABBAGE CASSAROLE In bottom of roaster pan, place 1/3 of =^ 1kg cabbage chopped cabbage and a little salt. Mix 5dl water together grounded meat, rice, chopped 3dl rice onion and spices. Lay this mixture over 0,5 teaspoon salt cabbage. Then cover the mixture with 1/3 300 g ground beef 01 chopped cabbage and salt. Lay the rest 1-2 chopped onion of mixture over cabbage and top with tespoon salt remaining cabbage. Pour over water in 0,5 teaspoon white pepper cassarole. Cover and bake 3 hours in solar powder box cooker. (2-3 tablespoon syrup) CARROT CASSAROLE i, ===,1 Mix together finely grated carrots, rice, -. eggs, milk and spices. Pour over,.,. ingredients in cassarole, cover and bake 2 1 milk 6..,, i,- ^i. 6-7 to 3 hours in solar box cooker. carrots 2eggs 1-2 teaspoon salt 1/4 teaspoon white pepper MEAT-VEGETABLE CASSAROLE.1 Put meatcubes, chopped onions, chopped 500 e meat onions and all other ingredients in 2onion cassarole. Cover the cassarole and bake in 2tomatoes ^^ ^ox ^e^" 1 (o 2 hours. 1dl cooking oil salt black pepper season as you like