Experiment

A solar cooker uses the energy of the Sun to cook food. An essential part of all solar cookers is a reflector. This is a shiny surface that reflects and concentrates the Sun’s energy. There are many possible shapes, but most use a bowl shape.

This solar cooker, designed by a student at SMK King George V in Seremban, Malaysia, uses 12 trapezoid-shaped panels. The panels are made from polycarbonate board and covered with aluminized plastic sheet. The sections are held together with flexible tape hinges. The bottom is a round piece of polycarbonate covered with aluminum foil.

In the center of the solar cooker is a pot with the food to be cooked. The pot is inside a glass enclosure. This traps heat and keeps the food at a higher temperature than would be the case without the enclosure.

The metal cooking pot is black so as to absorb more of the Sun’s energy. The enclosure is made from five square pieces of glass joined together with silicone glue.

Hafiz built a version of this solar cooker at a workshop in Malaysia in May 2008. It had 10 panels instead of 12 and used a plastic bag rather than a glass box to enclose the cooking pot. The temperature in the pot reached 86°C (187°F).

Design and Build Your Own Solar Cooker

Here are some things to consider when making your own solar cooker:

1. You need a shiny surface to reflect and concentrate the Sun’s energy on the food.
2. It is good to have an enclosure around the food to contain the heat. This prevents hot air from escaping. This will raise the temperature and speed up cooking time. The enclosure needs to be transparent so sunlight gets in. Glass or clear plastic will work.
3. Notice that the pot in the KGV solar cooker is black. A black surface absorbs more heat than a lighter-colored surface does. If you are using a pot to contain your food, it is best to get a black one, or to paint the exterior of the pot black. Use a nontoxic paint and make sure it is only on the outside of the pot.