Introduction: Solar Thermal Cooker
The goal of this project is to build a low cost solar cooker that could be used in any environment with access to the sun. It has the capability to cook food for families in third world countries. The maximum temperature achieved by the cooker so far is 300 degrees Fahrenheit. People interested in this project can range from a bored kid in Indiana to an Afghan family in desperate need for cooked food. Low building experience is needed, but only enough to safely use tools.
- 4 pieces of wood measuring 25"
- 8 pieces of wood measuring [30"x3"]
- 1 chicken wire measuring [33"x33"]
- 2 satellites or parabolic surfaces
- reflective tape
- 2 Sheets of wood [25"x32.5"]
- box cutters
- wire cutters
- Wood cutter
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Step 1: Understand Why It Works
Light goes under and through the chicken wire to the dish underneath and is then reflected to the bottom of the pan. It also hits the dish on top and reflects onto the top of the pan. The dishes should be calibrated so that the light underneath heats the pan in approximately the same spot as the top dish. This causes the energy from the sun to be focused onto one point. Nothing part of the solar cooker is meant to absorb heat, which is why a black pan or other container should be in the focal point. It has to be black or another dark color to counter the Albedo effect, where the color white reflects light away.
Step 2: Build Base
First you have to cut the legs to the correct height, which will depend on where the focal point of the bottom solar panel that will be placed on the bottom. second you will use four pieces of wood the will make the frame,which should be at least 3 feet by 3 feet, and screw them together to make the frame. The attach the legs on the bottom of the frame securely. Fourth, you will add chicken wire on the top of the frame and add 4 more pieces of wood to add on top of the frame to be able to secure down the chicken wire and hold the pot or pan, whatever you will be using. Then you add 2 pieces of wood about 2 feet in length that will be able to hold the top satellite in place, use screws to secure it from moving. Lastly you will need to use to pieces of plywood that will be used to block wind from cooling down the pan getting heat up, place them on the sides of the frame, leave an opening to allow the light to go in of course. You can use string or a bolt that will help keep the top satellite from falling, and use a cinder block or a piece of wood that will hold the bottom satellite in place as well.
Step 3: Attach Chicken Wire
Place the chicken wire on top of the frame. Use 4 other pieces of wood (around the same size) and place them on top of the chicken wire as well as the wooden frame. Screw in some screws into the wood to keep the wood and chicken wire together (around 10 screws should be good).
Step 4: Create 2 Parabolic Reflectors
Find parabolic objects such as old satellite dishes. Use reflecting tape and tape over every single space on the dish. As you are placing the tape on the dish, use a flat object like a credit card to slide over the tape and smooth it out.