Dan's Papers - August 17, 2007

Thought you've heard it all? How about using natural heat energy from the sun to make delicious homemade meals? Since the 1970s, solar cookers have been gaining popularity around the world and are now used in thirteen countries and five continents. They were invented back in 1767 by Swiss naturalist Horace de Saussure, who sought to trap solar heat in small-enclosed spaces, which were then called "hot boxes." Now known as solar cookers, they consist of cardboard, wood, or glass boxes with reflector devices (either mirror or aluminum foil) used to concentrate the light. Black pots (containing the food), whose dark color converts the light into heat energy, are placed inside the box. Finally, a transparent lid - like a plastic bag or glass cover - is used to trap the heat after the light has been absorbed, making outside air temperature a non-factor.

They come in three basic types: box cookers, panel cookers and parabolic cookers. While box cookers make for slow, steady cooking for larger food quantities, panel cookers consist of flat panels to direct the sun's rays onto a single pot. For as little as $5, you can purchase an easy-to-build CooKit, a relatively new type of panel cooker founded in 1994 by an international volunteer group. CooKits, which are being mass-produced in America, are meant for smaller portions of food to be cooked quickly in single pots. In order to avoid shadows, panel cookers must be directed towards the sun periodically throughout the day. Finally, parabolic cookers are made up of concave disks that concentrate the sunlight onto the bottom of the pot. Of all solar cookers, the parabolic bears the closest resemblance to conventional stoves, in that the food cooks at a similar rate. However, they're far more complicated to build and, like regular stoves, must be monitored since the food can overheat and burn. Also, they have to be manually turned towards the sun every 10 to 30 minutes.

In order to function properly, all solar cookers require direct sunlight and are most effective during midday hours, when the sun is highest in the sky and emits the most energy. According to Wikipedia, daytime clouds that exceed 25 to 30% are enough to prevent solar cooking. Regarding shadows, the Solar Cookers International website (www.solarcookers.org) claims that you need to have "the length of your shadow on the ground [to be] shorter than your height" for them not to get in the way.

This natural mode of cooking is environment-friendly. These cookers not only counteract the harmful pollution caused by conventional cooking devices, but also preserve nutrients, flavor and moisture in your food, making meals healthier and tastier. Since solar cookers tend to maintain more moderate temperatures than ovens, typically ranging from 200 F to 300 F, the food is cooked gently and evenly without burning. While multiple reflectors might simulate the cooking time of a normal oven, single-reflector box or panel cookers might take up to twice as long, but the food does not have to be monitored or stirred.

Most importantly, solar cookers are crucial survival kits for those 500 million indigent people in ten different countries - such as India, China and Pakistan - that suffer from fuel shortages. Solar cooking conserves one ton of wood per year per family of six people, and allows families in undeveloped countries such as Kenya to prepare nutritious foods that they otherwise couldn't afford. Refugees in such areas are often obliged to trade more expensive, healthier foods - such as legumes - for precious fuel material. Fortunately, many of them live in sunny, arid climates conducive to solar cooking, which can save them time, money and the energy it takes to find and carry wood fuel.

The natural cookers are also used for pasteurizing milk and water, as dangerous food microbes perish when liquids are heated to 150 F. The World Health Organization estimates that approximately 80% of all illnesses are transmitted through contaminated water, and that waterborne diseases such as cholera kill 50,000 people every day. Solar cooking not only minimizes wood-fuel needs by half but also helps prevent bacteria and viruses from prospering in drinking water. Seems like this kitchen-in-a-box, which is easily portable and requires just two minutes of cooking tasks, is a good deal. It conserves fuel, slows deforestation, provides nutrition and reduces waterborne illnesses.

To learn more about how to build and use solar cookers, visit the Solar Cookers International Website www.solarcookers.org or refer to www.solarcooking.org. To those brave enough to try, have fun cooking in the sun!