Square Foot Solar Cooker
AE-Zone post 4/18/2010
The Ft2 solar cooker.
This is the Square Foot Solar Cooker (Ft2) that has evolved from the original winebox rice cooker that I used at the Burn last year.
The winebox worked fine, but this is a far far superior cooker, and I want to share it with you in hopes you will make and use one at this year’s Burn.
Sadly I cannot afford to go this year, but would love to see any pictures of this thing being used out there, and learn of your cooking experiences with it.
I am thrilled with its performance.
Go to the hardware store and buy some square foot mirrors, the kind you use to tile bathrooms, etc. Don’t buy the beveled ones, they’re twice as expensive and bevels are not needed. A pack of 6 mirrors runs me about $12, and there are 6 in a pack, enough for two cookers. Make one for a friend….
Next you need some duct tape, a tube of silicon (optional), a can of black spray paint.
You also need, (depending on your uses), a couple of widemouth quart canning jars, a 1 and 1/8 inch spade drill bit, a wine bubbler cork (available from your local zymurgist, and pick up a bubbler, too…), and optionally some 3/8 copper tubing. (The last two items are not necessary for cooking only)
Finally you will need a gallon jar made of PET (#1) plastic. You can readily get these from your local bartender, as they are the jars that hold olives. Tip him/her a buck and ask to save a couple of those jars. If they use glass gallon jugs, so much the better, as I prefer glass.
You can make your cooker(s) either permanent, or break-down. I like both.
Permanent is great for around the house, and break-down is great for travelling light and folding flat.
The Reflector.
Now, since you Burners are above average intelligence people, I don’t need to tell you how to build the reflector, other than that you need to hold it together, and then add bits of duct tape to temporarily hold it in place. Then, place a full strip of tape along the seams. You should fully tape the two back upright reflector pieces, because then you can fold them backwards for flat storage and transportation. Or you can if you wish run a bead of silicon along the meeting inner edges, and after a few hours drying time it will be a one piece unit.
If you can’t figure it out, drop me a line….
The Inner Jars
For cooking, use good quality canning jars with sealable lids. Cover part of the jar with tape as shown, and the top screw on to keep it from getting painted, and then paint those suckers flat black.
When dry remove the tape to see the cooking window where you can watch your foods get done. And to see if they need more water.
Put the jars on the reflector for a couple of days before using to hard-cure the paint, and keep that paint smell out of your food.
The Outer Jar
You can use #1 PET plastic, #5 PP plastic (cherry jars), or good old gallon glass jars. I used glass for a long time, and then interestingly found out that #1 PET gets hotter than glass, and faster. Pick up a couple of plastic jars if you wish, because you can use them when not cooking to make an excellent raisin sherry. My first batch is wonderful, and knocks me on my ass after too many glasses…. I prefer the #5 PP jugs for winemaking for some reason, don’t know why, other than my work saves them for me.
Outer Jar Lids.
With a drill press or hand drill, and a one and 1/8 inch bit, drill a smooth hole through the center of the plastic jar lid. This will let you do two things, the first is to disinfect water, and the second is to allow you to insert a bubbler and cork to brew your own gallon of wine as above.
Water distillation, and potential alcohol distillation.
A good empty clean quart Coors beer bottle will make a water disinfector. Yes, I hate their politics, but I like the taste of their beer….
Place a nearly full bottle of water in the center of your outer jar. Carefully screw on the plastic outer jar top (the 1 and 1/8 inch hole lets the top of the beer bottle stick through — but DON”T put the cap on the beer bottle) Place this whole assembly on your reflector, and after about 130 minutes by my tedious measurements on a cold winter day, you will have reached 150 degrees which some say is the threshhold for disinfecting water. Surely on a hot summer day, it will be faster.
After 220 minutes, you are in the alcohol distillation range, and after 280 minutes you will be well into boiling range. At our Reno altitude, water boils at about 206 degrees, and that’s as high as it will go unpressurized. This unit, here, will boil water for as long as it has good sunlight.
As far as distilling alcohol, I understand that is illegal, and hence will NOT use my copper tubing into a water cooling container to try that….
Other dangerous considerations
A couple of days ago I said “Why not” and filled a mason jar 1/3 full of soybeans, and 4/5 full of water. After soaking overnight, I placed the unit in the cooker.
After a few hours, the soybeans were not nearly done, so, daringly, I tightened down firmly the mason jar lid and put it back in the cooker. And it got hotter, and hotter. Eventually I took it out into the kitchen and gently released the lid. Well, volcanic hot water spewed everywhere, and the thing foamed and hissed like a Hades nightmare. So I put it back out, as the sun was waning, and at the end of the day, after letting it cool on its own, carefully opened the jar. It was still wicked-hot, but lo and behold the soybeans were DONE. This is the very first time I’ve ever had soybeans cook fully in a solar cooker in one day.
I think my thermometer at max measured 260 degrees in the outer jar.
However, I caution you not to try this unless your are very daring and as stupid/foolish as I am. If you are like me, then please, be aware that the whole thing may explode on you — with great violent vigor –, and never ever set a hot jar on a cold or cool uninsulated surface, else you may be picking out shrapnel.
If you are foooooolish enough to try this, let it cool on its own, and then after several hours see if the beans are done. Soybeans in my opinion are NEVER done until you can squish them between tongue and palate, and if you can’t do that, then spit them out and keep cooking. Soybeans are incredibly filling, and possibly the reason we as a people don’t like them, is we’ve never tried a fully cooked one. A little soysauce, possibly with rice, and some nice nutritional yeast stirred in, oooo, heaven.
Further thoughts
You MUST be careful with this cooker. If you were to trip and fall on the glass mirror assembly, it may puncture an organ or cause a serious sudden loss of blood. It is potentially deadly lethal if left lying around. So don’t leave this about for the unwary, because someone or yourself may trip and fall on it and puncture themselves and fucking bleed to death. And be aware, I never use the F word in my writings, EVER, so please take care….
I hope you will build and use a couple of these before and during the burn this year, and since I cannot afford to go, please send me pictures and an email or so about your adventures with it. I would be greatful.
If you build yourself a couple of these cookers, you will be able to have 40 ounces or more of good cooked food in the evening when you take a break from your revelries. Without needing tracking or any care at all. Just fill your inner cooking jars with food, place on the reflector, put on the outer jar, and point the right hand edge of the cooker to where the sun will be when you want to eat. Fill it and forget it.
I am posting this tonight, with the hopes that my photos will embed here. I am a computer novice, and they may not upload. Or they may be greatly oversized. If so, and you are computer literate, perhaps you could email and help me to get all this stuff posted. I would be greatful.
Ya got a couple of months yet to experiment with this, so get to it….
Thanks and peace to you.
ChefCraig
(Craig Bergland)
email renofreepress (at) charter.net or post on AEZ list.
Thanks
And finally, please remember
Careful! Remember, All Intense Glares Blind Eventually!!! Repeated Glaring Light AND lack of eye protection will seriously mess you up!!!
“Generators? We don’t got no generators. We don’t need no generators. We don’t have to show you no stinkeen generators…”
