Solar Cooking

In Kenya

On a sunny day, it can cook an entire meal for the whole family. 

Contents

• Introduction to Solar Cooking 

• Important Tips 

• Acquiring a Solar Cooker

• Purchasing 

• Building 

• From cardboard

• From wood

• Recipes

• Beverages 

• Grains 

• Fruits and Vegetables  

• Proteins ( Meats and Beans) 

• Baking

• Alternative Uses 

• Contacts Regarding Solar Cooking

Credits

Compiled and written by Michi Vojta, United States Peace Corps Volunteer (US PCV).

Major contributions from Barbara Ross, US PCV; Institute of Cultural Affairs; Solar Cookers International; Solar Box Cookers Northwest; and Gruppe ULOG. Graphics taken or adapted from Solar Cookers International and Gruppe ULOG.

Assisted by Prabha Prabhakar Bhardwaj, Women In Development Environment Network (WIDEN), Kenya for layout and Desk Top Publishing.

Reproduction

There are no limitations by patent laws for the reconstruction of solar cookers. Reproduction of information is encouraged as long as the source is acknowledged and a copy is sent to the author care of Peace Corps / Kenya, PO Box 30518, Nairobi, Kenya, East Africa.

Introduction to Solar Cooking

A solar cooker changes sunlight into heat and cooks food. It uses no fuel except the sun's energy--no wood, charcoal, gas, kerosene, paraffin, or electricity. The cooker works on three basic principles of physics:

1. sunlight is absorbed by dark objects and converted to heat;
2. shiny surfaces reflect and don't absorb energy;
3. light goes through transparent materials, while heat mostly doesn't.

Therefore, the cooker is basically an insulated box that traps sunlight to cook. The adjustable reflector increases the solar radiation through the glass (or polythene) panes. The black matte floor and pots of the cooker converts the radiation into heat, which does not pass through the panes, remaining inside the cooker and cooking the food.

Some advantages of the solar cooker are:

• the construction is simple, and the wooden ones are strong and durable;
• it is easy and safe to use, even around small children;
• the food cannot burn or overcook;
• food does not need stirring or turning, reducing supervision time;
• the foods' nutrients are preserved;
• germs and parasites are killed while cooking;
• the food is healthy, and the use of the cooker does not cause health problems;
• it does not produce smoke or otherwise pollute the environment;
• water is conserved in the closed system;
• it saves money and time on fuel and water costs;
• cooking pots are easily cleaned without scrubbing.

However the cooker does need sunlight to cook, so it cannot work indoors or at night. Also it does not work as well in the early morning, evening, or on cloudy days. It cooks slower than traditional stoves (three stone, ceramic clay-lined jiko) and cannot be used for deep frying, because heat escapes when the cooker is opened.

Important Tips

The outside temperature of the air does not greatly affect cooking, as long as the cooker is properly insulated. This is mostly true for the wooden cookers, as the cardboard cookers are already less efficient.

The bigger the cooker, the higher the temperatures. However, the larger cooker will take longer the hear up, as it has more air space.

If building a cooker, especially if using polythene / plastic for the window, use two separate layers to create still air space in-between, which will conserve heat better than one layer. The glass panes in the wooden cookers are usually about 3 cm apart (1 inch). If using polythene, be sure the material is taut enough and will not sag and cling together.

Clean the glass/polythene window each time you cook.  Any dirt reduces the amount of incoming sunlight, thereby decreasing the cooking efficiency.

Place the cooker in full sunlight. Again, the more light, the better it cooks.

Put the cooker out while you are preparing the food. The cooker will preheat, reaching the necessary temperatures sooner and cooking the food faster.

Have the food in the cooker before 10 am, preferably before 9. The best cooking hours are from 11 am to 1:30 pm, so start early.

Use less water and salt. Because the water and nutrients are preserved, so is the food's taste.

Cut the food into small pieces. Larger portions take longer to cook.

Use pots with lids and painted matte (emulsion, not glossy) black on the outside and top. Most normal cooking dishes are appropriate, and the dull color absorbs light and converts it to heat quickly. If no lid is used, a black cloth can be used. In addition, a cloth can absorb the moisture condensing on the glass, which hinders cooking. One exception: baking cookies and other foods.

Use large, flat cooking pots.  Food gets cooked faster in a large, light pot filled one-third full than the same amount of food in a small pot filled completely. plastic containers may melt of emit fumes, while clay vessels or other thick pots will take longer to heat.

Place small wooden blocks under the pots. This will lift the pots higher in the box, where the heat is (heat rises). Also, this will allow the warm air to circulate underneath the pot, heating the food from all sides. however, the space between the highest lid and the glass panes must be at least 2 cm to prevent breaking the glass.

Close the lid tightly.  Any heat escaping will also increase the cooking time.

Adjust the reflector so that the maximum amount of light enters the cooker.

If you leave for several hours during the day, position the cooker so that it will receive maximum exposure during the key hours--from 11 am to 1:30 pm, when the sun's rays are most direct.

Do not open the cooker once it begins cooking if you can avoid it. Any time the glass lid is opened, heat escapes and the temperature drops in the cooker. When baking items with yeast of baking powder, the cooker should not be opened at all, as the dough will fall.

Use pot holders to remove the pots. They get very hot.

Food left in the cooker will stay warm for several hours. This can be prolonged by adding flat, clay tiles in the bottom while cooking, closing the lid after cooking, adding pillows into the cooker to retain heat (similar to a haybox / fireless cooker) or even covering the cooker with a blanket when the food is ready. However, food left overnight in the cooker or at room temperature (after the cooker has cooled) can spoil.

Purchasing A Solar Cooker

Solar Cookers International (SCI) has demonstration models, made of aluminum-lined cardboard, that are collapsible for “easy transport”-- assuming you don’t travel on Kenyan dirt roads via mountain bike or matatu. Also they are extraordinarily expensive for cardboard, especially on a Peace Corps budget. However, Children's Earth Fund will donate SCI's cookers to people on the condition that it be used to demonstrate solar cooking to school children within three weeks of arrival and the new solar cooking chefs (the students) report their results.

In addition, SCI sells WAPIs, or Water Pasteurization Indicators. These handy devices contain a wax which melts at 69 degrees Celsius (158 degrees Fahrenheit)--just above the temperature at which water is pasteurized. Once the wax melts and runs to the bottom, the water is safe to drink. WAPIs are inexpensive and can be purchased direct from SCI.

Clevelab in Littleton, Colorado, offers Sunspot, a mini-cooker. Again, it is a bit expensive and shipping is outrageous, but it works wonderfully well for children and demonstrations.  Mini-models can be easily constructed from cardboard.

From experience, wooden solar cookers are generally less expensive to purchase than to build, unless your site is extraordinarily remote. If you travel by train, the cooker can usually be put into the cabin for no extra charge. The construction is time-consuming and the cost of individual parts expensive.  Nonetheless, the plans for the cookers have been included.

Wooden solar cookers can be purchased here in Kenya. TransWorld Radio (TWR) builds cookers at their workshop in Nairobi on Ngong Road (near Ngong Hills Hotel). The design is basic and the cookers are mass-produced to keep prices low--they sell the cookers “at cost.” Institute of Cultural Affairs (ICA), just off Ngong Road, sells cookers that are made at the Kabiro Polytechnic in Kawangware. These are a bit larger, sturdier, and consequently more expensive.  Also ICA offers courses designed to teach local artisans to build cookers and local women to use and disseminate information on them. These two offices are a ten minute walk apart. Both addresses are included at the end of this booklet.

Verein zur Foerderung kleintechnologischer Nutzung von Sonnenenergie or VKSE (roughly, Association for the Promotion of Small-Scale Use of Solar Energy), associated with ULOG, sends assistants throughout the Third World "when invited" to teach solar technology provides financial support for solar projects.

Building Your Own Solar Cooker

Cardboard panel cooker

This CooKit is designed by SCI and is presently used in the Kakuma refugee camp in Northern Kenya.  It or a similar type of cooker has been used successfully throughout the world, from France to the United States, from Nepal to Kenya, with minor modifications according to latitude.  The difficulty is in getting the plastic bags for cooking. However, if they are available, this may be a cheaper and more convenient cooker—easier to make, transport, and replace.

From cardboard

Items needed to build a cooker with outside dimensions of approximately 66cm x 54cm x 45cm:

• cardboard box , approximately 66 x 54 x 45

• piece of cardboard, larger than others (for the lid)

• another piece of cardboard, 56 x 44 (bottom)

• needle and thread (or one liter of glue, which can be diluted to a 1:1 ratio with water)

• aluminum foil, one roll

• wood shavings, balled up newspaper, or small pieces of foil-wrapped cardboard (for insulation)

• glass or clear plastic, approx. 66 x 54 (if you use plastic, use two layers)

• mabati, painted black matte 56 x 44 (or another piece of cardboard, covered with aluminum foil painted black)

• scissors or knife

• ruler

• pen / pencil

• pots with lids, all painted black matte

At each corner, cut from the top to Line 1 to create four flaps (see Diagram 1).

mabati in the bottom of the jiko to increase absorption.

The lid:

There are other methods for construction. Some of the more popular are included, though they are by no means the only ones.

• For the base, two boxes can be used rather than one tall box (box inside a box method). This method can be more difficult than the large box method, but if a large-enough box cannot be found, this will work.
• No insulation is necessary inside the walls as long as the insides are lined with foil (foiled still airspace). However, wood shavings or extra cardboard--remnants from the cutting of the base or lid—are usually fairly easy to acquire and take no extra work. Folded, foiled excess pieces of cardboard also can be sufficient.
• Two layers of polythene, separated by a cardboard filler, create a “dead air” space and therefore better insulate the cooker. It requires more work, however, and generally more maintenance.
• The polythene used for the window should be as transparent as possible. Greenhouse, or “hothouse”, plastic can be purchased at the Polythene Shop in Nairobi for a decent price, but it has not been thoroughly tested; preliminary tests seem promising. Glass is often not desirable with a cardboard cooker, especially if the cardboard is somewhat flimsy.
• I found a leather awl and shoe sole thread--ask the local shoe fundi for some—to be better than sewing needle and thread, as they are stronger and better able to pierce the multiple layers of cardboard. Sewing needles tend to bend and/or break, requiring a large number, and also prove hard on the fingers.

Recipes

Pasteurizing Water

Water can be cleaned to kill germs in a solar cooker. It need only reach 65 degrees Centigrade, not to the boiling point.  Fill the containers almost full with water and cover loosely. After pasteurizing, store the water in the same tightly covered  vessels to keep it clean. A Water Pasteurization Indicator (WAPI) can be used as well. Cooking time:  3 hours for 4 liters.

Milk

Fresh milk must be boiled to kill any germs within. This can easily be done with a solar cooker. However, if left too long (i.e., all day) the milk will be scalded.  Cooking time: 1 hour per liter.

Chai

Mix 2 parts of cold water and one part milk. Add sugar (this can wait until serving) and tea leaves. Stir upon removing from the cooker; it will look white and uncooked until the leaves are mixed. Cooking time: 45 minutes for 1 liter (3 servings).

Grains

Rice

Mix 1 part rice to 2 parts water. Add a little cooking oil or fat. Place in the covered pot. Cooking time: 1.5-2 hours.

Ugali

Mix one part maize meal with one part cold water. Stir well to avoid lumps in the ugali. Add salt if desired. Do not open the cooker to beat of flip the ugali. The pot is much easier to clean than with traditional cooking style. Cooking time: 2-2.5 hours.

Lasagna

1 liter spaghetti sauce   parmesan cheese

.5-1 kilo each ricotta and shredded mozzarella cheese  .5 kilo lasagna noodles

In bottom of roaster pan, pour 1/3 of the spaghetti sauce. Coat uncooked noodles with ricotta cheese and make a bottom layer in the pan. Add half the mozzarella.  Repeat to make a second layer.  Top with remaining spaghetti sauce and parmesan cheese. Cover and bake. Cooking time: 4 hours.

Fruits and Vegetables

Mixed Vegetables

A variety of  vegetables can be prepared in a similar fashion, alone or mixed. Wash and cut vegetables like cabbage, carrots, tomatoes, green beans, potatoes, cauliflower, brocolli, eggplant, mushrooms, etc. Cut onions, and meat if desired, and fry in fat. Add all the prepared vegetables along with 1 cup water, salt and spices (beef cube) to taste. Stir well, making sure that all vegetables are wet. Cooking time: 2.5-3 hours.

Cooking Bananas

Place the green bananas into the pot without any additional water. (The peels with maintain enough water.) Peel before eating. Cooking time: 2 hours.

Bananas Deluxe

Fry meat (minced), onions, and tomatoes in fat or cooking oil. (This can be done on a regular cooker or in the solar cooker before the rest of the ingredients are added.) Peel and cut (dice) bananas. Add potatoes as well, if desired. Add to the meat, stir well, and add 1 cup water, salt, spices (beef or chicken cube), half a teaspoon sugar. Stir so that all the bananas are wet. Cooking time: 2-2.5 hours.

Githeri

Soak beans in cold water overnight. Fry onions and tomatoes in fat. (This can be done on a regular cooker or in the solar cooker before the rest of the ingredients are added.) Add one part soaked beans to one part maize, enough water to cover all the food and then more (it will absorb water as it cooks), salt and other spices to taste. Stir well so that all the ingredients are wet. Cooking time: 3-5 hours, though the longer you cook it, the better.

Mushrooms

Fry onions in fat.  (This can be done on a regular cooker or in the solar cooker before the rest of the ingredients are added.)  Wash mushrooms very quickly to make sure they do not absorb too much water. Cut into thin slices and add to the onions. Sprinkle with 1 teaspoon of wheat flour, stir well, then add a half cup of water, half cup of milk, and salt and spices (chicken cube) to taste.  Stir again. After the food is cooked, add a teaspoon of butter to increase the creamy taste. Very good with rice or ugali. Cooking time: 45-60 minutes.

Pineapple Yams

Peel and dice yams.  Add pineapple chunks and a cup of juice. Bake uncovered. Cooking time: 2 hours.

Boiled Potatoes

Wash potatoes of similar size and place them, still wet, into the pot. Add very little water into the pot (approximately .5 cm).  Cooking time: 2.5 hours.

Baked Potatoes

Wash medium sized potatoes, rub the skin with fat or cooking oil, and place them into the pot without extra water. After 2-2.5 hours, remove the lid from the pot and bake another 15-30 minutes to achieve the typical "baked" look.

Sweet Potatoes

Cook the same as the boiled potatoes: Wash the potatoes well and place them wet into the pot with 2 cm water. Cooking time: 2-2.5 hours.

Ratatouille

Fry quite a lot of onions and a bit of finely cut garlic. (This can be done on a regular cooker or in the solar cooker before the rest of the ingredients are added.) Add the washed and cut zucchini, green peppers, eggplants, and many tomatoes to the pot, along with one cup water, salt and spices (beef or chicken cube) to taste. Stir well, making sure all the vegetables are wet. Cooking time: 2-2.5 hours. Ratatouille goes well with ugali or rice.

Sukuma Wiki / Spinach

Wash the leaves, removing the stems and bad parts. (For the spinach, keep the stems, for higher nutrient content.)  Chop leaves. Fry meat, onions and tomatoes in fat. (This can be done on a regular cooker or in the solar cooker before the rest of the ingredients are added.) Add the wet sukuma and a half cup water, salt and spices to taste.  Cooking time: 1.5-2 hours.

Vietnamese-style Vegetable Soup

more than 1 liter water   tofu, pressed dry and cut into strips (opt.)

4-5 Tbsp. tamari or soy sauce     green or red chilies to taste

juice from 1/2-1 fresh lime (or lemon)     mint leaves (4-6 per bowl)

4-10 cloves of garlicwatercress (1 bunch per bowl)

4 large slices of fresh gingercilantro (1 small bunch per bowl)

1 large onion, sliced in strips       basil leaves, fresh (2 per bowl)

1 carrot, thinly cut diagonally      mushrooms, fresh (a few per bowl)

All ingredients except the mint leaves, watercress, cilantro, basil leaves, and mushrooms until the carrot is almost tender. Remove cooked ginger. Pour into bowls.

Proteins (Meat and Beans)

Beans are generally presoaked in cold water overnight to soften the outer coat and therefore reduce cooking times. This, however, is not absolutely necessary, though allow for longer cooking times if they’re not soaked.

Beans (mungbeans, red beans, etc.)

Soak the beans in cold water overnight.  Fry minced meat and onions in fat. (This can be done on a regular cooker or in the solar cooker before the rest of the ingredients are added.) Add sliced tomatoes and chopped bell peppers. Stir well and add the soaked beans, cover with water and add an extra cup, salt and spices (chili cubes, etc.) as desired. Stir again. Cooking time: 3-4 hours, though the longer it cooks, the better.

Baked Chickpea Casserole

• 1.5 cups dried chickpeas (garbanzos)    
• 2 tsp. black pepper
• 1/2 cup oil (preferably olive) 
• 4 cups chopped tomatoes
• 2 medium eggplants, cubed with skins on
• 1/2 cup parsley
• 3 medium onions, sliced into 1/4” rounds 
• 1/2 tsp. cayenne pepper
• 4 tsp. salt

Soak beans in cold water overnight.  Cook beans until tender; drain. Add the rest of the ingredients and cover. Bake again until tender. Serve with bread (preferably pita). Cooking time: 3.5-4 hours (??).

Boston Baked Beans

• 2 cups navy or pea beans   
• 1/4 cup molasses
• 2 tsp. salt    
• 1/2 tsp. dry mustard
• 1.5 Tbsp brown sugar    
• 1 large onion

Soak beans in cold water overnight. Cover beans with cold water, adding all other ingredients.  Stir to mix. Leave the onion whole and push it down into the center of the pot. Cover and cook, adding water if needed. Serve with brown bread and cheese. Cooking time: 4 hours (?).

Refried Beans

• 1 cup dried pinto beans 
• chopped onions
• 3 cups water

Soak beans in cold water overnight. Combine all ingredients and bake. Drain but save the liquid. Mash the beans adding liquid to get the desired consistency.  Add seasonings to taste--cumin, salt, garlic, pepper, etc. Cooking time: 4 hours.

Spicy Mexican Beans

• 2 cups pinto beans 
• 2 Jalapeno peppers, minced and seeded
• 6 cups water
• 3 Tbsp. lemon juice
• 1 large onion, chopped fine 
• 1/4 tsp. cinnamon
• 3 tsp. salt    
• 1 bay leaf
• 1/3 cup oil   
• 1 1/2 cups grated cheese
• 1 cup chopped, peeled tomatoes

Soak beans in cold water overnight. Cook beans until tender; taste and adjust seasonings as necessary. Put grated cheese on top and cook until melted.  Serve with rice and corn tortillas or cornbread. Cooking time: 3-4 hours.

Turkish Lemon Beans

• 1/2 kilo dry pinto beans 
• 2 tsp. brown sugar
• 8 cups water
• 1/2 tsp. black pepper
• 3 Tbsp. salt 
• 1/4 tsp. cayenne pepper
• 1 onion, chopped 
• 1 tsp. paprika
• 4 carrots cut into 1 inch rounds   
• 1 large potato, peeled and chopped
• 1/3 cup tomato sauce    
• 2/3 cup lemon juice

Soak beans in cold water overnight.  Put beans in pot with water, salt, and onion. Cook until almost tender. Add the rest of the ingredients and cover. Continue cooking until tender. Cooking time: 4 hours.

Boiled Eggs

Wash the eggs and place them in the cooker and cover them with a black cloth (or place them without water in a pot). Cooking time: 20 minutes to 1 hour. If you leave them all day in strong sunlight, they may burst.

Fish

Wash the fish or fillets in fresh water. Dry them in a clean towel or household paper. Rub the fish with a little salt and pepper on both sides. Cut onions and tomatoes in slices and sprinkle them with a little salt, pepper, and spices. Fry the fish on only one side and then turn it over. Dress the cut onions and tomatoes in the pot around the fish and add very little water, about 2 or 3 spoons full. Serve the fish together with rice or potatoes. Cooking time: 1-1.5 hours.

Chicken

Cut the chicken into nice portions, rub them with salt, pepper, and other spices. Fry the pieces shortly on both sides (with a regular cooker). Remove the chicken, then fry cut onions, sliced tomatoes, and/or sliced mushrooms in the same fat. Add the chicken back into the pot and one cup of water, pepper, and other spices (chicken cube). When serving, taste the soup and add additional salt, if required.  Cooking time: 2-2.5 hours.

Meat (Beef, Lamb, Pork, Goat, Rabbit, etc.)

Chop onions and garlic, and add to the minced meat. (The larger the pieces of meat, the longer the required cooking time.)  Fry with cooking fat. (This can be done on a regular cooker or in the solar cooker before the rest of the ingredients are added.) Add, if you like, a small amount of cut cabbage, 2 to 3 medium carrots, 4 to 5 sliced tomatoes, and green pepper. Stir well. Add salt, pepper, and other spices (beef or chili cube) to taste.  Add very little water, only the amount you would like as soup when the cooking is finished. Stir well again to be sure everything is wet. Cooking time: 2.5-3.5 hours, though the longer you cook the meat, the more tender it becomes.

Termites

Spread termites (preferably already dead) onto a baking pan. Cook until done.

Baking

Baking requires a lot of heat, so choose a clear, sunny day and preheat cooker for an hour or so before baking. I recommend putting the food in before 11 am, though baking in the afternoon or even twice a day has been done.

Banana Bread

• 2 cups flour 
• 1 cup mashed bananas (approx. 3)
• 1/4 tsp. salt 
• 3 Tbsp milk (or water)
• 1 tsp. baking powder     
• 1 tsp. vanilla extract
• 1/4 cup butter      
• 1/2 cup chopped nuts (any kind)
• 3/4 cup brown sugar (or 1 cup white sugar)

In a bowl mix flour, salt, and baking powder. In a separate bowl, beat butter and sugar until light and creamy. Add the bananas. Now alternately adding the banana mixture to the flour mixture in three shifts, also add, slowly, milk (or water) and vanilla. Stir until blended, then fold in chopped nuts. Optional: spices, such as cinnamon, nutmeg, cloves, can be added for flavor; the bananas can be soaked in one cup of strong black coffee for an hour before mixing into the batter. Pour the dough into a slightly oiled loaf pan (or pot) and only partially cover the pan with the lid, leaving a 2 cm opening. Cooking time: 2.5-3 hours.

Biscuits/Crackers

• 1-1/2 cups white flour    
• 1/4 cup sesame seeds, roasted
• 1-1/4 cup maize, cassava, or sorghum flour    
•  less than 1/2 cup water
• 1 tsp. salt    
• 1 egg, beaten
• 2/3 cup oil or melted butter/Blue Band

Blend flour and salt.  Add oil (or melted Blue Band).  Add water as necessary to make it manageable. Roll out into approximately 1/2 cm thickness. Sprinkle seeds on top, using egg to make it stick. Bake until golden brown. Cooking time: 3 hours.

Bread

• 1/2 kilo wheat flour 
• 30g yeast
• 1/4 liter lukewarm water or milk with 
• 1/2 teaspoon salt

Prepare yeast according to instructions on package (usually dried yeast powder requires mixing with 4 times its weight of warm water). Let this rise for 10 minutes. Do not use the solar cooker to hurry this, as the dough will harden and a crust will form, inhibiting the rising process. Pour the flour into a bowl or a clean smooth surface. Dig a small hollow in the middle of the flour and pour the liquid yeast in it.  Mix some more of the flour with the rising yeast and let it rise again for a few minutes. Now begin mixing carefully all the flour with this yeast mixture and slowly add the water/milk and salt until you have a nice, smooth dough. If the dough is too wet, add more flour.  Put the dough back into a bowl, cover with a clean, damp cloth and let it rise in a warm place for about an hour.  After kneading the dough for a second time, form it and place it into a cake pan or pot which had been rubbed with fat and dusted with flour. Place it in the preheated cooker with the pot not completely covered---leave a slit of about 2 cm. Cooking time: 3 hours.

Fancy Bread

• 1/2 cup sugar (brown or white, honey or molasses)
• less than 1/4 cup oil (or none)     
• 2 cups flour and/or grains (good combination: 1c white flour, 1/2c oatmeal, 1/2c corn meal)
• 1 tsp. baking powder  
• 1 tsp. cinnamon or other spice
• 1/2 cup raisins or chopped dried fruits or nuts
• 1 or 2 pieces or ripe mashed fruit (banana, orange, etc.)
• 1/2 cup liquid (fruit juice, milk, water, etc.)---use more if needed for soft dough

Mix all ingredients together well, and smooth into dark pan, Cover. The last hour can be uncovered if using dark grains. Cooking time: 3-4 hours.

Brownies

• 1/2 cup shortening 
• 3/4 cup flour
• 2 oz. unsweetened chocolate      
• 1/2 tsp. salt
• 2 eggs   
• 1/2 tsp. baking powder
• 1 cup sugar 
• 1 cup nuts (optional)
• 1 tsp. vanilla

Melt shortening and chocolate together (25-30 minutes in solar cooker). Cool. In a separate bowl, beat eggs until light. Stir in sugar, then chocolate mixture and vanilla.  Add dry ingredients and mix well.  Add nuts last. Pour into greased round pan. Cooking time: 2.5 hours.

Coconut Cookies

• 5 egg whites
• 250g sugar
• 250g coconut flakes   

Beat egg whites until very stiff. (Add a pinch of sugar to make it go faster.) Add carefully sugar and coconut flakes. Mix well.  Drop mixture with a teaspoon onto a very lightly oiled pot lid or other flat plate and place in the preheated cooker without covering. Cooking time: 1 hour.

Custard

• 1 egg     
• 3 Tbsp sugar
• 1 egg yolk   
• 1/4 tsp. salt
• 1 cup milk   
• 1/2 tsp. vanilla

Mix all ingredients.  Sprinkle with nutmeg. Cover and bake. Cook before serving. Cooking time: 1.5 hours.

Baked Fruit (and Meringue)

• apples, peaches, pears, bananas, etc.   
• 3 egg whites
• brown sugar 
• 1 tsp. vanilla
• cinnamon    
• 3/4 cup sugar

Cut up fruit, removing pits, cores, and bad parts. Places slices into a pot. Sprinkle brown sugar and cinnamon on top. Cover. Cooking time: 1 1/2 hours or longer.

Meringue topping:  Beat egg whites until stiff, adding vanilla and sugar while beating. Spread on top of cooked fruit and return to cooker, uncovered. Serve hot or cold. Cooking time: 1 hour.

Granola

• 6 cups rolled oats
• 1 cup soy flour
• 1 cup almonds, walnuts, or other nuts(finely chopped/ground)  
• 1 cup powdered non-fat milk
• 2/3 cups honey    
• 1 cup wheat germ 
• coconut, raisins, sesame seeds, cinnamon, etc. can be added  
• 1 cup salad oil

Mix together everything except oil and honey. Add oil and honey last; stir occasionally while baking. Cooking time: 2-3 hours.

Hot Fudge Sundae Cake

• 1 cup flour   
• 1/2 cup milk
• 3/4 cup sugar      
• 2 Tbsp. salad oil
• 2 Tbsp cocoa       
• 1 tsp. vanilla
• 2 tsp. baking powder     
• 1 cup chopped nuts (optional)
• 1/2 tsp. salt 
• 1 3/4 cup hottest possible water

In a pot, mix flour, sugar, cocoa, baking powder, and salt with a fork until smooth. Fold in milk, salad oil, vanilla, and nuts.  Beat until smooth. Pour hot water over batter. Bake. Cool for 15 minutes before inverting onto serving plate. Top with ice cream (!!!) and spoon hot fudge sauce over all.  Cooking time: 1.5-2 hours.

Maize Cake (Cornbread)

• 3 cups maize meal 
• 1/2 cup melted butter (or oil)
• 3/4 cup sugar      
• 1 cup milk (or water)
• 4 tsp. baking powder     
• 1/2 cup raisins
• 2 pinches salt      
• 1 lemon peel, grated (optional)
• 2 eggs

Mix the maize meal, sugar, baking powder, and salt in a bowl and add the raisins and lemon peel.  In another bowl beat the eggs, add the oil, and mix well. Add this mixture to the flour mixture and knead well by slowly adding the milk until you have a slightly wet dough. You may need additional liquid, but only add a little at a time; the dough should not be too wet. Fill the dough into a greased cake pan or pot. Put in the preheated cooker, without covering the pan completely with the lid--leaving a small gap (2 cm). Cooking time: 2.5-3 hours.

Oatmeal Squares

• 1 egg, beaten      
• 1/2 tsp. nutmeg
• 1/2 cup honey      
• 1/2 cup butter, melted
• 1 tsp. vanilla
• 1/2 cup chopped nuts
• 1/2 cup whole wheat flour    
• 1 cup quick cooking rolled oats
• 1/2 tsp. soda

Cream together egg, honey, and vanilla. In a  separate bowl, sift together flour, soda, and nutmeg. Add butter, nuts, and oatmeal to flour mixture. Add creamed mixture. Mix well.  Pour into greased pot. Cooking time: 1-2 hours.

Roasted Nuts

Spread nuts onto a flat dish or pot lid. Sprinkle with salt if desired. Can be covered with a black cloth to hide the treat from prying fingers. Cooking time: peanuts, 2 hours; almonds, 1 hour.

Alternative Uses

1. Disinfecting equipment. Medical objects, such as bandages, can be disinfected by using a solar cooker and water heated to the boiling point. Items that must remain dry can also be sterilized once the cooker reaches 149 degrees Celsius (300 degrees Fahrenheit), so a thermometer is necessary.

2. Preserving ("canning") foods. This is a tricky process that can be dangerous if improperly done, so please be sure that you reference other sources or have experience canning.  Fill the jars with the fruit, water, juices, etc., and loosely cover. Heat in the cooker until the liquid begins to boil over. Tighten the lids and remove from the cooker to cool.  (Reference s include The Expanding World of Solar Box Cookers by Barbara Prosser Kerr.)
3. Fireless cooker.  The "haybox" cooker has been in use for a long time. Cook the food in a covered pot until it has boiled briefly (varies with the food; in Kenya, most foods require 5-15 minutes), then quickly place into the cooker, surrounding the pot with pillows or other insulation.  There should be little or no free air space. The trapped heat will continue to cook the food slowly, as it cannot escape.
4. Drying foods. Place a tray of food to be dried on top of the glass / polythene window, in front of the reflector.  Inside the cooker, the moisture will not escape, and the extra light from the reflector discourages insects.  If insects or larvae are still a concern, spread the dried fruits into a preheated cooker and cook for 20 minutes, stirring once half way through.

For the purchase of solar cookers, WAPIs, or publications, or for further information, contact the following agencies:

TransWorld Radio (TWR) Institute of Cultural Affairs (ICA)

Solar Cookers International (SCI)      

Sunspot

(Sunspot--mini-cooker)

Clevelab
Box 2647
Littleton, CO 80161 USA

Children's Earth Fund
40 West 20th Street
New York, New York 10011 USA

(212) 727 4493

Verein zur Foerderung kleintechnologischer

(assistance--technical, financial)

Postfach CH 4011
Basel, Switzerland CH-4054  

Nutzung von Sonnenenergie (VKSE) Gruppe ULOG

  (construction models)

Morgartenring 18
Basel, Switzerland

Kerr Enterprises