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Create a solar powered oven using a pizza box.

Solar powered pizza box oven made from aluminum foil

Experiment to create a real oven using a pizza box

Does your family head to the kitchen table whenever they hear a fire siren? Do you get even with the neighborhood bully by inviting him to dinner? Does your dad refer to the smoke detector as the “oven timer”? It sounds like your family might need cooking lessons. We can’t provide cooking lessons, but we sure know how to make a cool little oven – out of a pizza box! And while we’re at it, we’ll learn how thermal collectors can collect sunlight and convert solar radiation into heat.

The Sun and solar energy and solar thermal collectors

The sun is the ultimate form of energy and has produced it for billions of years. Solar energy, or solar radiation, can be converted to other forms of energy – electricity or heat. Almost 200 years ago, John Herschel invented a “solar thermal collector box” that used sunlight converted to heat to cook food. Today, solar thermal collectors, or solar ovens, are of great use in countries where electricity is not available. In some cases, they are used to heat and purify water which means that this great invention actually saves human lives.

Thermal collectors come in many types but each of them works in the same basic manner.

  1. First, they concentrate sunlight usually using a mirror or reflective metal surface. They attempt to collect or reflect as much sunlight as possible into a smaller, concentrated space.
  2. They also use some sort of black surface to convert the sunlight to heat. Black absorbs sunlight and when it does, it gets very hot.
  3. And lastly, after the sunlight is collected and turned into heat, the heat that is produced is trapped, usually using a clear plastic or glass covering to hold the heat in (while still allowing the sunlight to get through).

Create a pizza box oven experiment

Here’s how to create a thermal collector using a pizza box and aluminum foil.

  1. Glue black construction paper to the bottom of a pizza box.
  2. Glue or tape aluminum foil to the inside top of the pizza box. Keep the foil as flat as possible. Any wrinkles will decrease the amount of sunlight we collect.
  3. Position the lid so it reflects the sunlight onto the black construction paper.
  4. Put a glass of water, marshmallows, or anything else you want to heat up or cook in the box
  5. Cover the entire box with plastic wrap

The box will be able to reach temperatures over 150 degrees. With a mirror-like reflective surface, the box could reach even higher temperatures. With a glass covering, the box could get even hotter and could actually replace a regular household oven.

Create a pizza box oven experiment advance notes – parabolic thermal collectors

A parabolic thermal collector is the most powerful type of thermal collector.  It concentrates sunlight at a single focal point via one or more parabolic dishes — arranged similarly to a reflecting telescope focusing starlight or a dish antenna focusing radio waves.

There are two key phenomena necessary to understand the design of a parabolic dish. One is that the shape of a parabola is such that incoming rays are parallel to the dish’s axis and will be reflected toward the focus, no matter where on the dish they arrive. The second key is that the light rays from the sun arriving at the earth’s surface are almost entirely parallel. So if a dish can be aligned with its axis pointing at the sun, nearly all of the incoming radiation will be reflected towards the focal point of the dish — most losses are due to imperfections in the parabolic shape and imperfect reflection.

A parabolic thermal collector uses a parabolic reflector to focus the sunlight onto a receiver. The parabolic reflector is a curved mirror that is shaped like a parabola. The mirror is positioned so that it reflects the sunlight onto the receiver, which is located at the focal point of the parabola. The receiver is usually a tube or pipe that contains a fluid, such as water or oil.

Parabolic thermal collectors are highly efficient at collecting and concentrating sunlight, and can reach temperatures of up to 400°C. They are commonly used in solar power plants and in industrial applications where high temperatures are required.

Required supplies for the Create a pizza box oven experiment

Supplies: Plastic wrap, Glue, Aluminum foil, Construction paper, Pizza box

Image Credits

In-Article Image Credits

Solar powered pizza box oven made from aluminum foil via Wikimedia Commons by Gerry Dincher with usage type - Creative Commons License. September 3, 2012

Featured Image Credit

Solar powered pizza box oven made from aluminum foil via Wikimedia Commons by Gerry Dincher with usage type - Creative Commons License. September 3, 2012


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