Principles
Simple solar cookers use the following basic principles:
- Concentrating sunlight: A reflective mirror of polished glass, metal or metallised film is used to concentrate light and heat from the sun into a small cooking area, making the energy more concentrated and increasing its heating power.
- Converting light to heat: A black or low reflectivity surface on a food container or the inside of a solar cooker will improve the effectiveness of turning light into heat. Light absorption converts the sun's visible light into heat, substantially improving the effectiveness of the cooker.
- Trapping heat: It is important to reduce convection by isolating the air inside the cooker from the air outside the cooker. A plastic bag or tightly sealed glass cover will trap the hot air inside. This makes it possible to reach similar temperatures on cold and windy days as on hot days.
- Greenhouse effect: Glass transmits visible light but blocks infrared thermal radiation from escaping. This amplifies the heat trapping effect.
Read more about this topic: Solar Cooker
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