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Technorati : desertification
The solar cooker is an extremely simple and innovative piece of technology that can be used anywhere that has decent sun coverage to cook any food that a conventional oven can. Unlike a conventional oven, however, with the exception of the initial cost to build or buy one, solar cookers are completely free to run. Using the basic principals of reflected heat from solar energy, solar cookers use no electricity, and require no wood to burn.
You can use solar cookers to:
- Steam and boil
There are three main kinds of solar cookers:
- Box cooker (aka “solar oven”), the most widely used solar cooker
- Curved concentrator cooker (aka “parabolic solar cooker”), requiring more attention and frequent readjustment but good for large-scale cooking
- Panel cooker, which combines a box cooker and a curved concentrator cooker.
- People living in developing countries often resort to using fuel wood for cooking fires, resulting in massive deforestation, which leads to erosion and evaporation of the water table, which can lead to desertification, and high emissions of harmful smoke. Using a solar cooker eliminates the need for people to spend long hours foraging for firewood, and cuts down on greenhouse emissions from cook fires. Cooking over a fire is estimated to be as harmful as smoking two packs of cigarettes a day, which can lead to many respiratory illnesses such as pneumonia.Solar Household Energy, Inc goes into more specifics:
- In many countries, women and young children spend hours a day in smoky cook houses. The biomass (wood, animal dung and crop residue) used as fuel gives off toxic smoke at about seven times the safe limit set by the U.S. Environmental Protection Agency, (EPA).LINK According to the WHO, every twenty seconds a person dies from this condition known as Indoor Air Pollution (IAP).LINK IAP can lead to lung cancer, low birth rate, cataracts, bronchitis, TB, higher infant mortality and asthma as well as pneumonia and other respiratory infections which are the biggest killers of children under five years of age in the developing world.LINK
- Smoke inhalation is not the only health risk. Women and children also suffer back and neck injuries from gathering and carrying fuel wood.LINK Children often burn themselves by falling into cooking fires.LINK The injuries and diseases caused by the use of cooking fires can only be relieved by introducing less labor-intensive and cleaner cooking methods.
Solar cookers’ part in reducing deforestation and desertification and reducing the use of electricity derived from fossil fuels is invaluable.
As Charity Guide says in its article on how solar ovens can make a difference:
- Home appliances are the world’s fastest growing consumers of energy, second only to automobiles. Items such as stoves, ovens, and refrigerators account for 30 percent of electricity use in industrial countries and 12 percent of their greenhouse gas emissions. In the United States, an estimated 5 percent of its fossil fuel consumption is dedicated to the cooking and distribution of food. A portion of that energy expenditure could be eliminated by using solar ovens.
- While solar cookers don’t require special pots and pans, dark colored, thin-walled pots with lids (clear is better so you can see the food without opening the solar oven and letting heat escape) work best for maintaining heat. One pot specially designed for solar cooking is the HotPot, a dark pot that sits inside of a transparent glass pot with half an inch (1.3 cm) of air between them and a clear lid. The dark pot and the layer of insulating air help maintain temperatures. This pot can work with any solar cooker, but was designed to work with a panel cooker.Solar cookers are also great for pasteurizing milk and water so that it’s safe to drink. Cooking time varies among solar cookers, and it is usually a good idea to start cooking in the morning to have the food prepared for midday. Basic aluminum foil and cardboard models often reach only 100 F (38 C), but this temperature is sufficient if you are willing to take longer to cook. Other solar cookers designed with better materials can maintain far hotter temperatures. Well insulated cookers can even be used to cook in the snow, as long as there is sufficient sunlight.
- The most acclaimed solar oven I’ve found is the Global Sun Oven, a box type cooker, which can reach temperatures from 360 F (182 C) to 400 F (204 C) with its four reflectors. It can fold up into the size of a small suitcase for easy travel, weighs only 21 lbs (9.5 kg), has a built-in thermometer (Fahrenheit and Celsius), is adjustable for maximum use of sunlight, practically spill-proof, and has lots of other efficient goodies (I really, really want one). Best of all, food cooked in the Global Sun Oven can stay warm for hours, and cooks in about the same amount of time as a conventional oven.