Solar Cooker
A solar cooker (SC) is a device that cooks food without any external heat source other than the sun. Currently the greatest use of SC’s is by humanitarian organizations. All over the world there are vast deserts and barren terrain and areas so remote that power is not available. Other popular uses for SC’s are solar powered homes, wilderness camping or living, back country adventures and SC fans. While there are over 60 designs available there are some basic principles necessary for practical application purposes and 5 standard styles:
Trapping Heat: A cooker is not effective if it can’t retain the heat from the sun, so the first consideration is the type of lid used. A clear element, such as glass or plastic not only pulls in the sunlight it turns it into heat and with a tight fit over the pot it maintains a good temperature for cooking. This can be achieved regardless of the weather.
Attracting the Sun: Sunlight must be drawn toward the SC and then concentrated for maximum cooking temperature. This is done with reflective metal like aluminum or a small mirror.
Light to Heat: Black naturally attracts heat, think of heat rising from a paved road on a hot day, you can see the shimmer of the heat waves. A SC is based on that principle. Black anywhere inside will help cook the food. Optimally ta black pot or pan will cook the food the fastest.
These basic principles are applied in full or pairs to create 5 basic styles.
Box Cooker: Sizes can range from a one serving meal to a built in unit in a solar house. Most are made of wood with a glass top (these can be hard to work with) while a single server is usually made from cardboard. Temperature max is 150 degrees Fahrenheit.
Panel Cooker: This is probably the most user friendly and most inexpensive SC on the market. It consists of shinny reflective material on cardboard which is folded onto a bowl shape. A black pot is placed in the reflective bowl, this is covered with plastic and placed in the sun. The concentration of the sun is so intense it can produce a meal for a family of 5 in a matter of hours. It can concentrate the suns rays better and faster than most and has been widely used in Darfur.
Solar Kettles: These SC’s rely on solar thermal technology. A black pot is suspended in an evacuated solar glass tube, the lid is glass and fits tightly. By using only solar energy these SC’s get quite hot and can even keep heated water hot overnight.
Parabolic Cookers: These are difficult to use and maintain and are mainly used for institutional cooking, therefore this type is not practical for this discussion.
Hybrid Cookers: These are a cross between a box cooker and a conventional oven. Because they rely on electrical power for cloudy or rainy days they haven’t really caught on yet. However, since they can be made from all recyclable materials or thrown away items this type is truly revolutionary.
Solar Cookers have many advantages such as the food need not be watched over as the food cooks slowly over several hours. SC’s use the suns energy to operate and do not rely on conventional power. Some drawbacks: Longer cooking time than conventional ovens must be used in peak daylight hours, most meals have to start cooking in mid to late morning, and some do not work on cloudy days. Finally, SC’s are very beneficial and some would say life savers. The best advice here is to research what will suit your needs
