If it’s easy and free, it’s too good to be true, right? Not when it comes to solar cooking.
Just as the term suggests, this cooking method captures the power of the sun. It’s a passive process, accomplished simply by a combination of reflecting, concentrating and absorbing.
Rice, beans and lentils are perfect for solar cookers. You can also bake meatloaf and lasagna, simmer chili and soups, prep potatoes for potato salad and slow-cook baby back ribs before finishing them on the grill.
When done correctly, air temperature becomes a non-factor, and solar cookers have even been used in Mount Everest base camps. In addition, solar cookers can be of huge benefit in places where firewood is scarce, people can’t afford to buy cooking fuel or access to safe drinking water is an issue; the ovens get hot enough to sterilize water.
In fact, depending on the type of solar oven, temperatures can reach 350 to 400 degrees Fahrenheit. So, although fried foods aren’t a good option, you can cook almost anything you normally would with a conventional oven, stovetop, crock pot or food dehydrator.
Any recipe that calls for long, low and slow cooking would be a great match.
The first step in solar cooking is to reflect and concentrate the sun’s rays with some sort of a shiny parabola (shallow dish shape) surrounding the oven. This can be accomplished with materials as low-tech as cardboard or aluminum — DIY plans abound on the Internet – or in more formal ovens constructed out of wood, metal, glass and so forth.
Angle is important, so the oven should either be facing the direction that gets maximum direct exposure throughout the day or periodically refocused toward the sun. Some solar ovens have tilt adjustments to take advantage of the rising and setting sun locations.
The resulting heat is accentuated and absorbed by using black surfaces. The walls of the oven should be dark, as should the cooking vessels themselves.
Depending on the oven type, the heat is contained via a plastic bag or by a door that shuts tight.
“One can cook in just about any container, the darker the better,” said Phyllis Davies, one of several local volunteers who demonstrate solar cooking techniques.
“The best results are from black containers with glass or black lids,” she said.
Thin black enamel cookware is a great option, Davies said, but cast iron is not recommended because “it is heavy, takes a long time to heat up and reacts with acid(ic) foods.”
“Glass jars placed in a black cloth or sock work well too,” Davies added, “and it’s easy to provide a lid for some containers by simply stacking a larger pot or cooking sheet on top.”
Many uncut foods such as squash, potatoes and apples can just be placed whole in the oven — use a trivet to keep them above the water that will condense inside — and a tray of cookies doesn’t need a lid at all.
When dealing with bright reflections and hot surfaces, kitchen mitts and sunglasses are a must. However, you won’t need to use that protection often during the cooking process. Once you get the hang of it, solar cooking is a fairly carefree process.
“Before work in the morning, place foods in your oven, face the oven toward the noon sun and, at the end of the day, come home to a delicious, nutritious hot meal,” Davies said. “You've cooked with no fuel cost and no (carbon dioxide) emissions.”
Davies’ introduction to solar cooking came in 1999 when she traveled to Kenya to teach gardening in orphanages and training centers. She returned to Kenya in 2004, and took a similar trip to Burundi in 2005.
“I saw several communities there using the sun to cook their food, thereby saving fuel and trees,” she recalled. “I began seriously solar cooking after that. It was so simple and effortless. Food cooks with no other fuel but the sun — which is free!”
For information about local solar cooking classes and/or volunteer opportunities, contact Phyllis Davies at Phyllis@daviesco.com or Marcia Alter at firstname.lastname@example.org, and check out the SLO Solar Cooks Facebook page.
For information about solar cooking in general, visit the Solar Cookers International website, solarcookers.org. The site also sells cookers and accessories.