A solar cooker is essentially a well-insulated box with a window made of glass or plastic through which the sun rays can get in. Inside, the bottom and walls of the cooker are covered in black to absorb the sunlight and release it as heat. Black cooking pots should be used to increase the heating effect. In Africa, temperatures up to 170°C or slightly higher can be reached this way.
Diversity of models In addition to the original types, sometimes called "cooking box" or "solar owen", there are many other models like parabolic reflectors, hybrid designs, funnel reflectors or drum cookers (made with one half of an oil barrel). There is also a different working principle for solar driers. Other designs can be seen in solarfood.de, www.eg-solar.de and www.solarcooking.org.