I made one a bit differently for cooling the cabin of my boat while anchored out in summer. In my case, I used a 36 quart cooler chest, a piece of plywood paneling, and a 72mm computer fan which only draws .04 amps at 12 volts. The fan is very quiet and puts out a huge volume of air. I placed two 10-pound blocks of ice in the cooler chest and when it was 85 degrees outside, inside the boat's cabin it was 68 degrees - nice and comfy for sleeping.
Cheers,
Gary
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