The first time I ever saw solar cookers was on the news in the summer of 2009 (though that would make it their winter, as I was living in Chile at the time), as part of a development project in the north, which is mostly desert. I had no idea solar cookers were so markedly simple in all various facets, such as appearance, use, and construction, and ever since then, it always remained on my to-do list to make one of my own.

Another added benefit that I was unaware of is that a solar cooker works at any time of year, so long as it's receiving direct sunlight (i.e. not cloudy). The many benefits of this clever creation far outweigh any shortcomings, and the only one I can even think of is that it takes longer to cook, but with a little planning and forethought and perhaps some added engineering/ingenuity, that can easily be overcome.

Photo of a small black box inside a larger box that is covered with foil.

Our homemade solar oven.

Photo of a pan of sliced red peppers and chopped carrots.

Our delicious test product.

Photo of a box covered with foil and with a pan of peppers inside. The pan is covered with plastic wrap.

The oven in the sun.

There are various styles of solar ovens to choose from and each requires a slightly different set of materials. I settled on making what seemed to me the simplest, as the only materials you need are:

  • 2 boxes (one slightly smaller than the other)
  • Insulation/stuffing (e.g. newspaper)
  • Black construction paper (black non-toxic paint can also be used)
  • Plastic wrap
  • Aluminum foil
  • Tape

More detailed instructions can be found online by doing a search for “homemade solar oven” and choosing whichever design fits your needs and budget best. If you have a pizza box, EERE even has instructions for building a pizza box solar oven—could be a fun project to do with your kids.

I didn’t get a chance to take a picture of the “final product” (which obviously still looked exactly like the initial product as my attempt ended in failure), but I did see some condensation on the plastic wrap, which meant that at least some heat was getting trapped inside my solar oven. I'm not quite sure exactly what went wrong, but I think some of the reasons mine didn’t work were:

  • Not enough sunlight—next time, I will try to put it out earlier so that it has more hours in the sun.
  • Poor taping job—next time, I will use more tape and maybe even glue or caulk, so as to better trap the heat; I may also buy a small sheet of acrylic plastic or a window with tempered glass to use instead of plastic wrap.
  • My “helper” for the project was an applied mathematics major as an undergrad – next time, I’ll try to find someone with a real engineering background!

If this fifth grade classPDF can successfully make a solar oven, there’s absolutely no reason why I, as a fully functioning, 26-year-old adult, can’t successfully make one, too!

Moon Choe is a summer intern for the Office of Energy Efficiency and Renewable Energy and second-year law student at the Ohio State University Moritz College of Law.