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Square foot solar cooker for bread and as an assist.

Picture of Square foot solar cooker for bread and as an assist.
You can build one of these for under $20 and a little scrounging.
 
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Step 1: Yeast water heater

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The little Ft2 cooker will bake bread, but it is only in small batches.  However, that should make it elligible for this topic of Bread Making. As seen below, you must not put too much dough in your jar, as it tends to blow-out the lid. Still working on this part of it.  And it does a lot of other things. It will allow you to use solar to heat your yeast water, etc. It will bake bread, but until I can find the right combination of jars, I use it mostly for other cooking things.  
For example, we know that yeast does better with warm water, and this reduces the rise time of the dough. To heat my yeast water, I fill the quart jar 3/4 full, add a spoon of sugar, and then a round teaspoon of yeast.  Set the whole assembly on the cooker, in the sun, and let it heat up.  In good weather, the water may rise as much as one degree a minute, so be sure that the temperature does not exceed about 100 to 110 degrees or you may kill off your yeast.
When the mixture is hot enough, then add it to the rest of your water in your recipe, and start your bread rising.
 

Step 2: Building the reflector

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First, you assemble three square foot mirrors as shown.  You can put them together with duct tape, however it is very important that you put a good backing on your assembly to give it strength and to lower the chances of the mirrors breaking if you were to carry it and fall.  Kind of like running with scissors, we don't do that. Please always use caution. Also I like to seal it with silicone to help hold it together.
This configuration of the mirrors works very well, and is so simple to construct.  The cooker puts out about 80 watts by my calculations, and the mirrors will only cost about 6 bucks per unit, or $12 for 2 cookers.

Step 3: Inner cooking jars

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The next component is the inner cooking jar.  This is a quart widemouth canning jar, which will take pretty high heat.  Paint the outside black to help it quickly absorb the sun's energy, and let the paint bake while on the reflector for a day or two to set it.  Note, you can also use the quart jar as a sprouter for sprouted wheat breads.  Soak your grain overnight, add a screen to the top, drain, and rinse several times a day until your sprouts are grown to your satisfaction.
The cooking jar as doubles as a bowl to eat out of, a storage container for leftovers, and with the metal lid removed, can be put in the microwave to heat up your food the next day.  Only one container to wash!!!
These jars are so handy I buy them by the dozen, and use them a lot.
 
 

Step 4: Outer insulator

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The 3rd part is the outer covering jar.  I use several kinds, and they should be available from your local bar.  Tip the bartender a buck and ask them to save you some jars.  I use both glass, and PET plastic jars.  The PET are good, because the quart canning jars will fit easily inside of them, otherwise you have to search for skinny quart jars to fit inside of the glass gallon ones. Also, the white PP jars will work, but not as good.
Often you can cook without the outer insulating jars if it is warm outside.  In winter, though, you do need the extra layer of insulation.
Normally you just set the outer jar over your cooking jar as shown.

Step 5: Mini wine casks

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One more use for the outer jars, is to make wine in.  All you need is a hole in the lid, a cork, and the addition of a bubbler, and drill holes as shown.  Makes great wine, takes a couple of weeks.  Simple recipe is 9/10 gallon of grape juice, add a good wine yeast, cork it with the bubbler, and set it in a warm place until it quits bubbling.  Or you can use a pound of raisins soaked overnight then ground up, a couple cups of sugar and some good yeast.  Be sure to sterilize all equipment with a solution of chlorine/water first.  Please experiment at your own risk, and read up on how to do it properly. And you must be 21.
It would be interesting to use the dregs of the wine to try as an additive with different breads, as they may add tannins, and certain other grape tastes to the dough.  If anyone has tried this, please share your experiences.
 

Step 6: Basic cook techniques

The Ft2 cooker will also do many many other things.
 
Cooking rice/grains.  Fill the quart cooking jar 1/3 full with dry rice.  Add double the amount of water.  Set in the sun, top on the jar loosely, with outer cover on, and in about 2 to 2 and 1/2 hours your rice will be piping hot.  You can set this in the sun before work in the morning and it will be hot when you get home.  Position the cooker so that it points to about 3 O'Clock to have it done by 5 or 6.  No muss, no fuss, no tracking needed.
Set it and forget it.

Step 7: Safe water

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Disinfecting water.
I use a quart brown beer bottle, with a hole drilled in the top of the outer jar lid to accomodate the quart jar.
The FT2 will bring the water to a boil within 2 to 2 and 1/2 hours.  This is mostly acceptable as disinfecting temperatures.  Some folks think 150 degrees is safe, but near boiling is better.  We need minimally a quart of clean water a day to survive, and the cooker can give you on a sunny day at least 3 quarts worth. Don't tighten the cap of the brown jar, just set it on loosely!!!!
After disinfecting, just screw the cap down tightly, and store away from the sun.  You can also dip the cap in wax to help seal it.
 
 

Step 8: Legal solar stills

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Some friends and I do have a permit, to distill ethanol for fuel ONLY,  and here are pics of our other solar still, along with the Ft2 cooker still.  Don't even think about doing this without a permit!!!  They are not that hard to get.
I do not advocate, and strongly discourage any attempts to distill ethanol without a permit, and never ever should you distill for personal use unless you live in someplace like New Zealand where it is legal to do so.
However, it would not hurt to write your Congress folks and ask them to allow for personal small batch distillation, and change the laws.
 

Step 9: Melting wax the solar way

Picture of Melting wax the solar way
Safely melting wax.
You can make your own candles with this cooker without any fear of fire.  There is no flame, so no chance of combustion.  I use the wax mode for sealing my wine bottles after corking.  You can also safely melt for making your own candles. I generally leave one Ft2 at all times with wax in it, so anytime I need it, during a sunny day, it's ready.  While I've only used a 12 ounce can, certainly a larger one will do more wax.  Paint the can black, and you may not even need an outer covering jar. But it will be faster with one.
Jar is shown off the can for viewing purposes....
 

Step 10: Extra illumination

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The reflector as a light source.
If you put your candle (or kerosene lamp) onto the reflector, it will greatly increase the light output.
 

Step 11: Use year round

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I also use the square foot solar cooker to dry my washed jars, and if left long enough it will disinfect them too, as the jars can often reach boiling temperatures.
And I have also used it to make yogurt, soymilk, hummus, and cook a wide variety of vegetables.  Steamed onions are especially nice with a little soy sauce, and it will even hardboil eggs. I have sucessfully pressure cooker a quart of soybeans in it, and while it's kind of scary (the high pressure) it hasn't exploded on me yet.  I would not recommend doing this, though.
By the way NEVER set a hot cooking jar onto a cold surface.  Always set it on some kind of insulator or hot pad.
I keep finding more and more uses for this little cooker, and you can even make a collapsible unit for portability. I've made one with hinges and velcro to hold it together.
It works on a sunny winter day, too, and, if the wooden backing is well sealed and painted, it can be left out in the weather.  I've left one outside for several years now, and it is none the worse.
 

Step 12: Super cheapo Ft2 cooker

Picture of Super cheapo Ft2 cooker
And finally, if you don't have the mirrors, you can make one from cardboard and foil that works just fine.  Here is a picture of my original winebox solar rice cooker.  Worked great, but does not do well in the rain....