As part of Health Week, today we made our own solar ovens. These are common in other parts of the world, especially places where there might not be much fuel available. Using either a pizza box or a shoe box we created our own (instructions can be found below) and then we put the ovens out at lunchtime with some banana muffin mix inside.
When Mr Stanley collected the ovens in shortly after four o’clock, he was extremely pleased to see that the muffin mix was partially cooked and there was some significant heat in each oven. Bearing in mind that the temperature wasn’t particularly high this was quite an achievement.
The ovens will be stored away safely for a really hot day when we will try and melt cheese on slices of bread. Mr Burford is also going to rig up some boxes with temperature probes.
- Cardboard pizza box (the kind delivered pizza comes in)
- Box knife or scissors
- Aluminum foil
- Plastic wrap or Plexiglas (if available)
- Black construction paper or black ground cover
- Stick or dowel
What to Do:
- On the top flap of the pizza box draw a square with a marker with edges spaced 1″ from the four sides of the box.
- Use a box knife or sharp scissors to cut a flap in the lid of the pizza box. Cut along three sides, leaving about an inch between the sides of the flap and the edges of the lid. Fold this flap out so that it stands up when the box lid is closed. Cover the inner or bottom side of the flap with aluminum foil so that the rays from the sun will be reflected off. Be careful to make as few wrinkles as possible, and smooth out whatever wrinkles occur. This will be your reflector panel.
- Use clear plastic wrap to create an airtight window for sunlight to enter into the box. Do this by opening the box and taping a double layer of plastic wrap over the opening you made when you cut the flap in the lid. Leave about an inch of plastic overlap around the sides and tape each side down securely, sealing out air.
- Line the bottom of the box with aluminum foil to reflect heat and then cover that with black construction paper–black absorbs heat.
- Now your oven is ready to try out! Take it outside to a sunny spot and adjust the flap until the most sunlight possible is reflecting off the aluminum foil and onto the plastic-covered window. Use a stick or a dowel to prop the flap at the right angle.
Your solar oven will reach about 200 F. on a sunny day, and will take longer to heat things than a conventional oven, but can cook just as well.
For greater heat retention and better cooking results, use a shallow, black or dark colored pan, dish or pot that will fit inside the solar box cooker and place it inside of an Oven roasting bag (used for roasting turkeys) and then seal or tie the bag closed.This will create what is known as the “greenhouse effect”, trapping extra heat and retaining steam and moisture which will in turn maximize temperatures and cooking results.
If you wish, you may add some extra reflector panels on the side in order to increase the concentrations of sunlight into the box and onto the cooking pot, thus increasing your temperatures.