About 15 years ago I was laid-off from work and money got real tight. It was during the hottest part of the Summer ( the hottest summer of the century LOL). I needed away to stay cool at night so I could be well rested and ready to look for new work the next day.
I had reached into the freezer for a soda I wanted ice cold, it had froze solid. I sat it on the counter to thaw and came back later to find it half frozen and found a puddle of water dripping onto the floor from the condensation. Then it dawned on me that's exactly the way an air conditioning unit works...
Step 1: BOM
BOM (Bill of Materials)
4 2 liter soda bottles (with caps)
1 Cooking sheet
1 Box Fan
Duct Tape (one of mans greats contributions)