Sunny Science: Build a Pizza Box Solar Oven

An engineering enterprise from Science Buddies

Key conceptsEnergySolar powerSunHeatCookingRecycling IntroductionHave you ever eaten food that was cooked outside, such as for a BBQ or while camping? During the summer it can be a lot of fun to be outdoors and enjoy eating the fruits—or burgers—of your cooking labors. But you don't always need to burn wood, charcoal or gas to cook outdoors. Did you know that you can directly use solar power to cook food? This can be done using a solar oven, which is a low-cost, ecologically friendly technology. In this activity you will build your very own simple solar oven out of a pizza box to gather the sun's rays and—cook a tasty treat for you! BackgroundSolar ovens use solar energy—light and heat emitted from the sun—to cook food. They can also be used to pasteurize water or even sterilize instruments. How does a solar oven work? The simple answer is that it is designed to absorb more heat than it releases. The solar oven you will build in this activity is a relatively simple one made out of a pizza box, aluminum foil, plastic wrap and a sheet of black paper. You will cut a flap out of the pizza box's lid and line this flap with aluminum foil. This will reflect sunlight into the box. You'll also seal the opening with plastic wrap. This plastic "window" works like a greenhouse roof, allowing (direct and reflected) sunlight to pass into the box, while also retaining heat. At the bottom of the box, you will place black paper. This will act as a heat sink that absorbs direct and reflected sunlight to warm it, which will heat food placed on top of it. This activity also includes instructions for making a tasty s'mores treat that you can heat up in your own solar oven! Materials

Observations and resultsDid your solar oven get hot? Were you able to cook a tasty s'more using your oven? In this activity you built a simple box-type solar oven that should have been able to cook a s'more in sunny, warm conditions. In some trials using a solar oven that was made based on this design, at 85 to 90 degrees F on a sunny afternoon it took about 30 to 35 minutes for the marshmallow to get warm enough to become soft and melt some of the chocolate to make a tasty, solar-powered treat! In ideal conditions this solar oven can easily heat up to about 160 to 200 degrees F. Using full, direct sunlight is important for heating this solar oven—the sunlight needs to be reflected into the oven (primarily from the aluminum foil-covered flap, but also from the inside of the box), and the heat must be trapped and retained inside by the plastic "window." This heat is also absorbed by the black paper to heat the food that is placed on top of it. More to exploreSolar Energy, from the U.S. Environmental Protection AgencySolar Energy, from Kids & Energy ESD BulgariaNow You're Cooking!, from Science BuddiesSolar-Powered Water Desalination, from Science Buddies

This activity brought to you in partnership with Science Buddies

Lauren J. Young

Stephanie Pappas

Chelsea Harvey and E&E News

Meghan Bartels and Andrea Thompson

The Editors

Rina Diane Caballar