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The Haybox for energy conservation
Hayboxes (sometimes called fire-less cookers) work by keeping as much heat as possible inside the cooking pot once the food has been heated up. The heat held within the food, water, and pot is used to continue the cooking process. Using a haybox can save a lot of energy. After boiling food for a few minutes, the hot pot is placed inside an insulated box, where it finishes cooking. The retained heat is enough to finish cooking the food to completion; a haybox does all of the simmering for us, saving not only energy but effort as well. A haybox also makes cooking much easier. The cooking pot does not have to be guarded against boiling over or scorching. Foods such as rice, beans, pulses, stews, or vegetables, are boiled up in the usual way and put into the haybox for several hours, from where they come out hot and ready to eat. Hayboxes have been used for centuries in different countries. They work by insulating the pot, thereby keeping food hot enough for cooking to continue. The design is simple:
A wide variety of materials, besides hay, can be used for insulation. Examples of good insulators are: straw, rushes, hay, chaff, popped grain, wood shavings, sawdust, newspaper, fibreglass, feathers, cotton, sponge, fur, wood ash, charcoal, ground nut shells etc. Allow about four inches (10 cm) of wall thickness. If cork, laminated cardboard, crumpled aluminium foil or rigid foam (such as that used in buildings) is used, only two inches (5 cm) is needed. One of the most efficient hay-boxes is made by filling the air space around the pot with cushions, held in place inside a box. Another simple method is to use two boxes, one inside the other. The space between the boxes is filled with insulation. An insulated lid fits over the top. This works even better if the pot sits on a pot-rest, such as a piece of plywood or rigid plastic packaging foam. Another type of haybox is made from a double bag of fabric lined with insulation. A drawstring closes the top. The neck of the bag should open wide so that the pot can enter and be taken out easily. A haybox can be something very simple like a hole in the ground. The pot is placed inside the hole on a bed of insulation. It is wrapped in a skin or plastic or oiled cotton bag. The bag keeps moisture from wetting the insulation. The space around the bag is filled with hay, straw, small pieces of foam plastic used in packaging etc. and is covered by a closely-fitting cover that keeps the air out. The hole can also be made in a block of sand/clay on a raised platform so as to be more accessible. Remember that earth is not good insulation. It does not contain little pockets of air. It is the air in the straw, for example, that slows down the passage of heated air and allows the pot to remain hot, and finish cooking. Wet straw loses a lot of its insulating qualities. Simmering food in a haybox will take one and a half to three times longer to cook than on a cooking stove. Cooking a large amount of food works better than a small amount, as it holds the heat better. A tight lid on the pot helps as well. Using one quarter less water with grains is necessary, since less water is evaporated during cooking. It is helpful to wrap the pot in a towel before putting it in the haybox. Cooking gets rid of dangerous bacteria in food, and to ensure that the same thing is true for haybox cooking, two things are very important:
Hayboxes save energy, reduce smoke and make life simpler, all at once.
[top] [end]Contents: Boiling Point 43: Fuel options for household energy
Categories: Boiling Point 43| Fireless cooker | ||||||||||||||
Page created:
19 July 2007; Last edited:
07 March 2008; Version: 3 | ||||||||||||||
Pagename: TheHayboxForEnergyConservation @HEDON: QXFA | ||||||||||||||
