Build your own solar oven
So the idea of a solar oven is that you use the suns power to cook your food, you basically make an insulated box and cover it with glass. Then we use mirrors to bounce more sun into our box, this makes it even hotter.
First we need an old window, I got mine from a construction site. Its your basic old nasty basement window.
Cut off the outside wood part so that you can get the glass inside. Take your saw and cut slowly on one side until you hit glass, then remove the wood. Be careful glass is sharp!
Now comes the "hard" part. By hard I mean it will be the most physical effort. you need to take your wood and make a box. What size wood you have that will determine what size box you make.
You want to make your box big enough to hold at least one pot. If you make a box that is too small it wont fit your pot, and if you make it too big it will not get hot enough because there is too much air to heat up.
I originally made a huge coffin like structure (we at The Sietch get a little excited about these things). I found that it just wouldn't get above 100 F, no matter how big my reflectors. I then cut it in half to a box 14 inches high and 26 inches wide and 17 inches deep.
A bit of measuring and cutting and nailing later and I had a nice little box made. I then went and raided the local dumpsters for cardboard.
If there is one thing you can count on is that there is always going to be lots of cardboard boxes laying around. No one will miss a couple boxes. Take your duct tape and line all the inside seams with tape. This will help to keep heat from getting out between the boards. Take your cardboard and line the inside of the box until you have about 1 inch of cardboard on the sides and bottom of the box.
I found that it was easiest to use large pieces of cardboard and jam them in tight instead of trying to use lots of smaller pieces and tape or glue them in. Pay special attention to the top of the box you want to make sure the cardboard is all one level so that it makes a good seal when we lay the glass on top of it latter.
When you are all done you should have a nice looking box with a nice smooth top. As you can see I have painted the box black (the tape was later painted black also). Make sure that you use paint that says "lead-free and nontoxic when dry." on the back. Unless you like lead, I find it rather bitter and not very good for seasoning.
I had a great find the other day while going through dumpsters some mirror!! I find these all the time but they are almost always broken, if you are not lucky enough to find mirrors you can use foil and cardboard (use a mix of white glue and a little water to affix it to the cardboard). You can paint the inside black as well to collect even more heat.
You might want to clean your mirror better than I did. Now here is the part I am going to leave to you, you need to find some way to affix the mirrors to your box so that you can reflect the sun into the box. I used some wood and rebar that I found to rig up a holder that sits separate from the box. But really the sky is the limit.
Some tips for solar cooking, put your food out in the morning with your reflectors facing south (or if you live in the southern hemisphere point it north), and when you get home it will be ready to eat. Most things take about twice the recipe cooking time. But the nice thing is you cant really overcook in a solar oven so once its cooked your food will just stay hot and ready to eat. Also if you can paint your pot black and put it inside an oven bag, this will make it get hotter faster and stay hotter longer.
You only need a day that is sunny 20 minutesout of every hour. If you can find some sheet metal and paint it black and put it in the bottom of your box it will collect heat and help to keep your food hot.It can go from ambient temp to 120 in about 10 minutes with cooking temps in the 250-275 range.
Have fun cooking with the sun.