Build a Solar Oven

Build a Solar Oven

Try this fun experiment and make your own solar oven using easy to find household items. When you’re set, you’ll be able to use the sun’s energy to cook outdoors. In this version, you can make your own S’mores. Yum!

Items Needed:

  • Cardboard pizza delivery box
  • Aluminum Foil
  • Clear Tape
  • Plastic Wrap
  • Newspaper
  • Scissors or utility knife (Make sure an adult helps with cutting!)
  • Ruler
  • Sheet of black construction paper
  • Pencil
  • The hot sun! (Pick a warm day, preferably above 85°F)
  • Graham crackers, Marshmallows, Chocolate Bar (S’mores ingredients)
  • Thermometer (Optional)

 

Steps:

  1. Using the scissors or utility knife, with an adult’s help, cut a flap in the pizza box lid. Cut along three sides only, leaving one inch between the edge of the box and where you cut. Fold the flap out so it stands up when the box lid is closed.
  2. Line the inside of the flap with aluminum foil, folding the edges of the foil over the flap to keep it in place. Tape down the foil and try to keep it as smooth as possible.
  3. Lift the lid and line the inside of the box with aluminum foil – shiny side out.
  4. Cover the opening made in the pizza box lid by the flap with plastic wrap. The wrap should be as airtight as possible. Tape the plastic wrap in place.
  5. Next, cut a piece of black construction paper so that it’s 2 inches smaller along each edge than the bottom of the pizza box. If you have a really large pizza box, you might need more than one piece of paper.
  6. Center the construction paper in the center of the bottom of the box, on top of the foil. Tape in place.
  7. Take newspapers and make four rolled tubes of newspaper out of multiple sheets of paper. Each of these rolls will go along the edges on the inside of the box, creating a border. Tape the rolls in place. Be sure the rolls do not stop the lid from closing.
  8. Using a pencil, create a “dent” in the box, where you can insert the pencil and use it as a “kickstand” for the lid to remain upright for cooking.
  9. The solar oven is finished! Take it outside on a sunny day while the sun is high overhead, between 11 AM and 2 PM when the sun’s rays are the strongest. Put the graham cracker, topped with a piece of chocolate, and a marshmallow in the oven.
  10. Close the lid. Prop up the flap you cut and lined with aluminum foil using the pencil.
  11. Let the sun do its work! It will take some time, but eventually, you’ll have a melty, gooey and delicious S’more to try.

How does it work?

This is a homemade version of a collector box, so called because it collects sunlight. The sun’s rays come to earth and reflect off the aluminum foil, where they bounce directly into the opening of the box. The air under the plastic wrap heats up and cannot escape. We used the black paper because it also absorbs heat, keeping the bottom of the oven warm. The newspaper acts as an insulator, helping to keep more of the warm air inside the pizza box.

If you have a thermometer, check the inside temperature of the oven when you take out your S’more. Reposition the box as you experiment so that it faces the sunlight and can absorb that heat.

You can also try other recipes that don’t need the heat of a conventional oven – nachos and cheese, baked potatoes or chocolate sauce!

Resources:

https://www.homesciencetools.com/a/build-a-solar-oven-project