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 The Solar Car Book A complete kit for making a cool solar racecar. Everything is included: wheels, axles, motors, wires and a genuine one-volt solar cell. |
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Build Your Own Solar Cooker
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Solar Chimney Solar Air Conditioning Solar Pond Salt Evaporation Pond Solar Furnace Solar Cooker Solar Still Solar Water Disinfection Solar Desalination A solar cooker, or solar oven, is a device which uses only sunlight to cook. Because they use no fuel and they cost nothing to run, humanitarian organizations are promoting their use worldwide to help slow deforestation and desertification, caused by the need for firewood used to cook. Solar cookers are also sometimes used in outdoor cooking, especially in situations where minimal fuel consumption or fire risk are considered highly important.
Types of solar cookersThere are many different types of Solar cookers. All solar cookers are based on a small pool of ideas to heat food with the sun's heat and light. The basic principles of solar cookers are:
Alone, each of these strategies for heating something with the sun is fairly ineffective, but most solar cookers use two or all three of these strategies in combination to get temperatures sufficient for cooking. Apart from the obvious need for sunlight and the need to aim the solar oven before use, using a solar oven is not substantially different from a conventional oven. However, one disadvantage of solar cooking is that it provides the hottest food during the hottest part of the day, when people are less inclined to eat a hot meal. However, a thick pan that conducts heat slowly (such as Cast Iron) will lose heat at a slower rate, and that combined with the insulation of the oven can be used to keep food warm well into the evening. The top can usually be removed to allow dark pots containing food to be placed inside. The box usually has one or more reflectors with aluminum foil or other reflective material to bounce extra light into the interior of the box. Cooking containers and the inside bottom of the cooker should be dark-colored or black. The inside walls should be reflective to reduce radiative heat loss and bounce the light towards the pots and the dark bottom, which is in contact with the pots. The inside insulator for the solar box cooker has to be able to withstand temperatures up to 150°C (300 °F) without melting or off-gassing. Crumpled newspapers, wool, rags, dry grass, sheets of cardboard, etc. can be used to insulate the walls of the cooker, but since most of the heat escapes through the top glass or plastic, very little insulation in the walls is necessary. The transparent top is either glass, which is durable but hard to work with, or an oven cooking bag, which is lighter, cheaper, and easier to work with, but less durable. If dark pots and/or bottom trays cannot be located, these can be darkened either with flat-black spray paint (one that is non-toxic when dry) or black tempera paint. The solar box cooker typically reaches a temperature of 150 °C (300 °F); not as hot as a standard oven, but still hot enough to cook food over a somewhat longer period of time. It should be remembered that food containing moisture cannot get much hotter than 100 °C (210 °F) in any case, so it is not necessary to cook at the high temperatures indicated in standard cookbooks. Because the food does not reach too high a temperature, it can be safely left in the cooker all day without burning. It is best to start cooking before noon, though. Depending on the latitude and weather, food can be cooked either early or later in the day. The cooker can be used to warm food and drinks and can also be used to pasteurize water or milk. Solar box cookers can be made of locally available materials or be manufactured in a factory for sale. They range from small cardboard devices, suitable for cooking a single meal when the sun is shining, to wood and glass boxes built into the sunny side of a house. Although invented by Horace de Saussure, a Swiss naturalist, as early as 1767, solar box cookers have only gained popularity since the 1970s. These surprisingly simple and useful appliances are seen in growing numbers in almost every country of the world. An index of detailed wiki pages for each country can be found here. 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. Elegant and deceptively simple looking, it is an affordable, effective and convenient solar cooker. It requires a dark, covered pot and one normal plastic bag per day or one high-temperature plastic bag per month. With a few hours of sunshine, the CooKit makes 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 US$3 - US$7. The new hand-assembled CooKits are expected to outlast the manufactured CooKits, which last for two years. (Adapted from a more extensive article on the CooKit from the Solar Cooking Archive Wiki) HotPot
The HotPot cooking vessel consists of a dark pot suspended inside a clear pot with a lid
A recent development is the HotPot developed by US NGO Solar Household Energy, Inc. The cooking vessel in this cooker is a large clear pot with a clear lid into which a dark pot is suspended. This design has the advantage of very even heating since the sun is able to shine onto the sides and the bottom of the pot during cooking. An added advantage is that the clear lid allows the food to be observed while it is cooking without removing the lid. Solar kettlesThe SK-TF (Solar Kettle-Thermos Flask) 
Solar kettles are solar thermal devices that can heat water to boiling point through the reliance on solar energy alone. Typically they use evacuated (or vacuum) solar glass tube technology to capture, accumulate and store solar energy needed to power the kettle. Besides heating liquids, since the stagnating temperature of solar vacuum glass tubes is a high 220 degrees Celsius (425 °F), Solar kettles can also deliver dry heat and function as ovens and autoclaves. Morever, since solar vacuum glass tubes work on accumulated rather than concentrated solar thermal energy, solar kettles only need diffused sunlight to work and needs no sun tracking at all. If solar kettles uses solar vacuum tubes technologies, the vacuum insulating properties will double up as a Thermos flask thus keeping previously heated water hot throughout the night into the morning to deliver that cup of hot beverage in the morning even before the sun is up. Hybrid solar ovenA hybrid solar oven is a type of solar oven that uses both the regular elements of a solar box cooker as well as a conventional electrical heating element for cloudy days or nighttime cooking. Hybrid solar ovens are therefore more independent. However, they lack the cost advantages of some other types of solar cookers, and so they have not caught on as much in third world countries. Hybrid solar grillA hybrid solar grill consists of an adjustable parabolic reflector suspended in a tripod with a movable grill surface. These outperform solar ovens in temperature range and cooking times. When solar energy is not available, the design uses any conventional fuel as a heat source, including gas, electricity, wood, etc. The tripod hybrid grill is revolutionary in that many, if not all, of the parts required to build them can be scavenged from commonly thrown away items. Shown here is the high quality hybrid solar grill. Portable Solar Cooker - PSCThe Portable Solar Cooker was created by xCRUZA’s Laboratory with
the premise and the objective to collaborate with the socialization of
the use of renewable and nonpolluting energies, through the
simplification and the optimization of the existing technologies. 
> Instantaneous: Its design allows a simple and practical arming and disarming for being used at any moment and place wanted. [Portable Solar Cooker by xCRUZA] Environmental advantagesSolar ovens are just one part of the alternative energy picture, but one that is accessible to a great majority of people. A reliable solar oven can be built from everyday materials in just a few hours or purchased ready-made. Solar ovens can be used to prepare anything that can be made in a conventional oven or stove — from baked bread to steamed vegetables to roasted meat. Solar ovens allow you to do it all, without contributing to global warming or heating up the kitchen and placing additional demands on cooling systems. Nearly 75 percent of US households prepare at least one hot meal per day; one-third prepare two or more. Some of those meals could be made in an environmentally responsible way, using a solar oven. The World Health Organization reports that cooking with fuel wood is the equivalent of smoking two packs of cigarettes a day. Inhalation of smoke from cooking fires causes respiratory diseases and death. One of the solutions advocated to address this problem is solar cooking which makes no smoke at all. It just uses free and abundant solar energy. Solar cooking projectsTrials in LesothoDiffusion of innovations theories, discussed in the book of the same name by Everett Rogers, discusses adoption of solar ovens in Lesotho. Although solar ovens were safer and cheaper to use than oil burning ovens, Lesotho women resisted using them. A similar negative conclusion was reached by a reviewer, who after the clouds rolled in had to wait many hours for lunch, and decided to return to conventional ways of cooking . Despite these negative test results, agencies such as the Peace Corps have tried to use change agents to influence the women to have less babies. But these change agents have differed from the women in class and norms and were not effective in spurring changes in the amount of babies. Researchers have found that the diffusion process works better if the change agent trains a local aide who belongs to local social networks and can better influence locals. Michael Hönes of Germany has been establishing solar cooking in Lesotho, enabling small groups of women to build up community bakeries using solar ovens [2]. Use in Darfur refugee campsMaterials for well over 10,000 solar cookers have been donated to the Iridimi refugee camp and Touloum refugee camps in Chad by the combined efforts of the Jewish World Watch, the Dutch foundation KoZon, and Solar Cookers International. The refugees construct the cookers themselves. This was done so that the Darfuri women wouldn't have to leave the relative safety of the camp to gather firewood, exposing them to a high risk of being raped, kidnapped, or murdered. [1][2][3] Indian solar cooker villageBysanivaripalle, a village in Andhra Pradesh, 125 km (80 mi) northwest of Tirupati, is the first of its kind — entirely solar cooking village — in India. Intersol, an Austrian non-governmental organisation, sponsored the provision of "Sk-14" cookers in 2004. [4] References
Rawlinson, Linnie, 'Solar lifeline saves Darfur women', September 17 2007, CNN.com, [3] See also
External links
This article is licensed under the GNU Free Documentation License. It uses material from Wikipedia Encyclopedia article "Solar Cooker" |
