Terra Cotta Fridge-a Part 1

Now this device that I'm going to show you only works when sunny and..:

I got to get started... What we are going to build is called a Zeer Pot. A fridge that runs on the sun, you'll need:
  2 terra cotta pots (one larget than the other)
  5' of thin plastic tubing
  Waterproof Silicone
  0.5 cubic feet of paver sand
  Duct tape
  Scissors
  A large towel (Not shown here)
  A gallon of water

 Step 1: Cover the bottoms of the pots with some duct tape

Step 2: Plug the holes on the other side with the silicone and let it dry for four hours

Step 3: Fill the bottom of the pot with enough sand so when you place the smaller pot in it, the rims level out

 Step 4: Get the tube, and plug one side with the silicone and let it dry for an hour

 Step 5: Wrap the hose around the smaller pot and tape it there

 Step 6: Cut some holes in the hose and test if water will run through it

 Step7: Place the small pot in the large pot

 Step 8: Fill the gap between the two pots with sand and put some sand on the bottom of the small pot

 Step 9: Wet the sand, but don't put a lot of water or else the small pot will float and create a big mess

 Step 10: Get your towel and soak it in water

 Step 11: Fill the pot with a little bit more water

 Step 12: Let it sit and wait for it to cool down. I stuck a thermometer in and out of the pots to compare the temperature

This works on the principle of water evaporation. When the water evaporates away, the heat is carried with it, and the inner chamber cools down. And this only works when the sun is beating down directly on the pot, and both the pot and towel have to be wet.

And how cold will it get...? See the next post for the chart.