When you loose power you no longer have the ability to keep your food cold in your refrigerator. Without opening your fridge you food will stay fresh for about 2 hour as long as the temp doesn't go above 40 degrees but if the power is out for more than 4 hours you will lose all of your perishable items you have stored (meat, poultry, fish, eggs, and leftovers).

Conventional refrigeration does an incredible job keeping food fresh. But that technology doesn't help without steady electricity. A more recent development in refrigeration—the Zeer pot-in-pot refrigerator—only requires water, sand, and a hot, dry climate to preserve produce through evaporative cooling. Here's how to make the simple gadget.

Materials and Tools Required

  • two terra cotta pots with a 2-3 inch difference in diameter. The smaller pot should be glazed and preferably lacking a drainage hole. If the inner container is double glazed (on its inner and outer walls), non-potable water—say seawater—can be employed.
  • a bag of sterile sand
  • a square of burlap cloth large enough to cover the top of the inner pot
  • a trowel

Building It

  • 1. If your pots have drainage holes, plug them with a bit of cork, caulk, or other waterproof material. If you don't, moisture from the sand will seep into the lower pot and immerse the stored goods or seep out the bottom of the larger one.
  • 2. Put down a one-inch deep, level layer of sand in the bottom of the large pot. Set the smaller pot on top of that layer and center it in the larger one. Make sure that the smaller pot's lip is even with the larger one's.
  • 3. Fill sand in around the sides of the of the two pots, leaving about an inch of space below the lip.
  • 4. Pour cold water over the sand until it is thoroughly saturated. Put your food into the smaller pot. Cover that with a burlap cloth, also soaked with water. That's it! Just be sure to refill the water regularly, about once or twice a day.

How It Works

The Zeer was developed in 1995 by Mohammed Bah Abba, a Nigerian school teacher that hailed from a family of pot makers. The design is incredibly simple: a glazed earthen ware pot nestled inside a larger, porous one with a layer of wet sand separating them. As the water evaporates through the surface of the outer pot, it draws heat from the inner one, keeping up to 12kg food fresh for as long as three to four weeks without using a single watt of electricity.
Thanks Gizmodo