Ive seen these things done before at the local solar fair, and i i figured it cant be too hard to make a small one
Step 1: Materials,
-One 80mm 12V computer fan and grill and mounting screws (these can be taken from computer cases or power supplies)
-Two, 9 volt batteries (I hope to replace these with a 12V solar panel soon)
-Two 9volt battery clips (probably moot if replaced with solar, but I may keep them for use in partial sun)
-Some cardboard, or black foam board
-Some black Duct Tape
-One length of dryer hose (probably best if its less than 10 feet mine is about feet long
I decided to make mine length wise, so i decided on what would be a top and a bottom, (both ends have handle loops so either end is just fine. just pick one.
I then took my foam board (black in this case, but cardboard painted black would work as well, probably better) I 2 rectangles about 6"x17.5" and duct taped them inside the top and bottom of the bag. I plan to get more foam board and make some sides and internal baffles but so far it works ok as it is.