Now I’m not much of a cook, but this is intriguing stuff. It doesn’t take much imagination to understand how hot surfaces can get. Just lay a bare arm on the hood of a car that’s sat under the sun. I’m sure you remember saying this a thousand times: its so hot, you can fry eggs on... you fill in the blank.
The technology is as old as the hills… well almost. Anyway, these cookers work just the same as any other solar collector, except they use the sunlight for cooking. Solar cooking is a gentle process. Cooking with an even soft temperature maintains the food’s moisture and nutrients. Burning and overcooking is a rarity.
The fuel is solar thermal energy provided by a very very hot sun 90 million miles from here. Think what you could do with one of these on the planet Mercury; well, maybe not Mercury, but how about Venus.
Obviously, the cooker needs to be set up where an abundance of sunlight is available. Equatorial latitudes plus or minus 40° work best, this means the further south you get the better. That is unless you’re south of the equator, then in that case, it’s the further north you get. Either way, you need sunny weather at least six months a year.
If at all possible, find a secure wind protected place. And be sure to use dark shallow pots and pans with tight-fitting lids. The lids are important because they hold the heat and moisture in. Then you can cook entire meals, bake bread, cakes, pasteurize water and milk, warm cold food, make warm drinks, make dried fruit, and keep the coffee or tea warm. Sound interesting?
BOX COOKERS
These operate at moderate to high temperatures. If they’re large enough, they can accommodate several pots and or pans. The walls of the box require very little space between the outer walls and the cooking chamber. The cooker box needs to withstand temperatures to 300°F without melting or out-gassing. Most of the heat escapes through the top (glazing) glass, so very little insulation if any is required.
Since this is likely to be a DIY’er project, the insulating material can be (best) scrap fiberglass batting, wool rags, etc. I’ve even heard of some using crumpled newspaper, but I wouldn’t be comfortable with it. I would prefer the fiberglass batting. As for the cover, you can use a pane of glass or a large oven-cooking bag. The bottom inside should be painted black with reflective (aluminum foil) material on all four sides.
If you have, dark colored utensils – great. Otherwise, they’ll need darkening. This part is easy, simply spray them with a flat black (non-toxic) paint, or use stove (black) polish. I prefer stove polish; the stuff used to blacken wood stoves, stovepipes, and such. A well-stocked hardware store will usually carry it. You could even soot them up with a small wood fire.
Remember, solar cooking is not cooking on a standard burner or oven. It’s best to start cooking before noon so the food will have plenty of time to get done. It isn’t necessary to use the high temperatures suggested in cookbooks. Your box will still get hot enough to cook the food though over a longer time. All the same, moist foods cannot get much hotter than 212°F anyway. There’s an up side, if food is left in a cooker all day, it won’t burn or dry out.
Solar cooking depends on the weather. You can’t expect to bake a loaf of banana bread if the sky is overcast. Neither can you cook an Alaskan caribou rib roast above the artic circle during the winter.
Drop down to the links section on the bottom of this page. You’ll find dozens of plans for box cookers. The link will also get you solar cooker plans for about every other kind of solar cooking devices on the planet. Okay, grab a couple of cardboard boxes, some aluminum foil, an oven bag and go for it. Set one up, and have fun.
Back to List.
CURVED CONCENTRATOR COOKERS
Don’t let the curved part throw ya. Actually, it’s really a simple parabolic reflector. Focusing the sunlight onto a dark colored cooking pot, makes it hot – very hot, very fast, and it does ’t require a heat trap.
Though this type is more difficult to construct, it is capable of reaching high temperatures (to 400°F) thus allowing faster solar cooking than the other types. However, they need frequent adjustment to track the sun, during which eye injury and burns can result if care in not taken when re-alignments are made.A concentrator cooker is a powerful device for solar cooking. Concentrator cooking methods are similar to cooking on single burners on a conventional kitchen range. Focusing intense sunlight onto a small closed oven raises its temperature to that of conventional ovens.
See the illustration for this variety. Oh yes, don’t forget the links section at the bottom of the page for solar cooker plans.
Back to List.
PANEL COOKERS
I’ve provided two panel cooker examples (a. and b.). Illustration (a.) is a typical panel configuration while (b.) is a hybrid panel (funnel) cooker. Both are inexpensive to construct. Aluminum foil placed over a backing of cut scrap sheets of corrugated cardboard make for an efficient heat collector.
Panel cookers and box cookers use a closed heat envelope or heat trap to store solar energy. A heat trap is nothing more than a plastic bags or glass bowel placed over the pot to hold the heat. Box cookers use a glass lid or oven bag to hold heat. Heat storage is not required for concentrator cookers, as solar energy is focused on the cooking vessel.
Solar thermal energy heats the pot and air inside the plastic bag. This covering creates a greenhouse effect, storing the energy. Meanwhile the food inside is delectably cooked. Actually, the panel cooker is the simplest and least expensive to make. You can put the whole shebang together in a flash, and with an almost nonexistent cost, why not get started.
Back to List.
There are so many designs from which to choose. For example, hikers can fabricate portable units that will fit in their backpacks. DIY’er can build a variety of very efficient solar cookers for backyard cooking. Solar cooking can be a great family project and the kids'll love doing hot dogs.
In fact, anyone interested in solar cooking can use ordinary materials found around the house to build one. Cardboard boxes, aluminum foil, black spray paint, oven bags, etc, etc. So, for less than the cost of a Mickey-D cheese burger, you can make both for yourself. The solar cooker and the cheese burger, that is.
Many are creating sumptuous meals and baked goodies out under the sun. Remembering that solar cooking retains more flavor and moisture than cooking with conventional appliances, is it any wonder that solar cookers are summertime favorites. And the best part, you needn’t worry about burning dinner.
For sure, solar cooked food retains far more of its vitamins and minerals and is thus more nutritious. So go ahead, fry can egg, bake a cake, create a casserole or boil a dinner. And remember this, the sun’ll be there tomorrow.
To see how it’s done, drop down to the link area and click on the plans section.Back to List.
HOW LONG DOES COOKING TAKE?
Using a solar oven, on sunny a day. It takes about the same time as it does to cook a meal indoors. The beauty is you can fill a couple of pots around noon then come back in the afternoon to a tasty meal, cooked to perfection.Panel cookers are slightly faster, because they cook smaller portions in a single pot. Using a parabolic concentrator is as fast as cooking on a conventional appliance burner. Concentrators get hot, and food will burn, so you may have to stir.
Regardless the method, solar cookers are fun, and leave no carbon footprint.
Back to List.
HINTS:
Use cast iron or heavy pottery when ever possible. They will heat evenly and hold it longer even when the afternoon sun has diminished. Develop your own recipes or find hundreds on the web.
Caution: as with any cooked food, the possibility of various bacteria producing heat resistant spores should the temperature drop to between 125° and 50°F is likely. Regardless whether kitchen appliance cooking or solar cooking, to be safe, all such food should be kept above 125°F to prevent the possibility of this happening. Food poisoning is no fun.
Reheating the food in question to normal cooking temperatures may prevent bacteria spoilage, but the risk of harmful bacteria present remains. At best, it would be wise to discard such food, especially if it’s set at such low temperatures for more than four hours. In any case, care must be taken to maintain food safety especially with meat and grains.
And finally, always use solar cookers to cook food or heat water, never for anything else.
Back to List.
LINKS
If you want to know more about solar cooking,
here’s the site
that will tell you more than you ever wanted to know.
Want to build your own cooker, there’s dozens of
DIY PLANS
here.
Want recipes,
here's a start,
Want more
try these.
Enjoy!!!
Back to List.
A solar cooker is a delightful device, glad you stopped in.
Using a solar cooker is a cool way to tickle your taste buds. Boil, bake, roast and steam, all with free solar power. Yap - the sun'll do it for ya, so why not?