How to Make Solar Cookers More Efficient
- 1). Paint the outside of your solar cooker black. If you have not done so already, painting the solar cooker black will enable it to collect and trap more of the sun's radiation-heat energy.
- 2). Install layers of aluminum foil on the inner walls to keep the light bouncing around as much as possible. Eliminate any black spots that might soak up the heat in the structure of the oven rather than conveying it to the cooking container. Add insulation underneath the aluminum foil so that heat is not lost by being absorbed by the body of the oven.
- 3). Use plexiglass or real glass for the window of the cooker. According to the Solar Cooking website, some people report that a glass window increases the performance of the oven by at least 10 percent over plastic windows. Glass also holds up better in windy conditions.
- 4). Angle your window. If you are able to fabricate an angled window, set it at an angle between 20 and 40 degrees so it will capture more of the sun's energy. In the winter, you will need to set your oven at 90 degrees in order to capture as much sunlight as possible.
- 5). Select more appropriate pots to cook in. Generally, dark pots that have been blackened and are lightweight work best. Use a pot that is only slightly larger than the food you are cooking in it to maximize transferring heat from the pot to the food itself. Graniteware pots reportedly work well with solar ovens because of their darker coloration. Avoid aluminum or cast iron.
- 6). Add mirrored reflectors on the sides, focusing the sun's energy into the box through the glass or plastic window. To install the mirrors use hinges that flex so the mirrors can move along with the sun if you plan on using your oven for a long time. You can attach the mirrors to the hinges by using construction adhesive or an epoxy as a bonding agent. Prop up the mirrors with small scrap pieces of lumber, sticks, rocks or cardboard.
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