A simple technology that brings fresh hope
The zeer pot is a simple fridge made of local materials. It consists of one earthenware pot set inside another, with a layer of wet sand in between. As the moisture evaporates it cools the inner pot, keeping up to 12kg of fruit and vegetables fresher for longer.
The Zeer or Pot in Pot refrigerator is an electricity free invention can keep food cool and fresh by the power of evaporation. It was invented in Nigeria by Mohammed Bah Abba in 1995. However there are reports that the technology was used in Ancient Eygpt.
It works using what’s known as evaporative cooling. As the water evaporates due to the sun, the water takes heat from the inner pot and makes it cooler.
What happens if we lose power indefinitely — foods that require freezing or refrigeration for long term storage are going to go bad? Emergency food storage in advance will be the only way to feed yourself and your family.
What makes this zeer pot practical?
There are other zeer pot instructables out there, but this one is optimized for practicality. If the capacity is too small, the cooling capacity too low, or if it an eyesore or is annoying to use nobody would want to use it. This zeer pot uses a large glass pot lid, has an interior basket divider, and sits on a rolling cart. It even has a layer of decorative pebbles over the sand to make it look pretty. The terra cotta pot legs hold the pot off the rolling cart with enough clearance to let the bottom surface contribute to evaporation; this adds about 10%-15% more evaporative surface. The inner pot is bolted down so that it doesn’t float up when you charge the pot with water. Nearly everything I used in this project was purchased at a hardware store, and it can be made in a few hours, plus a day to let the sealants cure.
I will be building a zeer pot array for A Place for Sustainable Living in Oakland (California) based on this design. The goal is to use an array of zeer pots to displace the use of at least one of their refrigerators. The design shown here is the outcome of my experimentation with making zeer pots for them.
(Be sure to read all the notes to all of the photos. Many important details are listed there.)
Making a zeer pot fridge
1 First, bowl-shaped moulds are created from mud and water – and left to dry in the sun. Clay is then pressed onto the moulds to form the desired size of pot. Clay rims and bases are added and the moulds are removed. The pots are left to dry in the sun.
2 Once the pots have been fired in a pit of sticks, the zeer pot is ready to assemble. A smaller pot is placed inside a larger one, and the space in between filled with sand.
3 The whole structure is then placed on a large iron stand. This allows the air to flow underneath and aid the cooling process.
4 Twice a day, water is added to the sand between the pots so that it remains moist. The entire assembly is left in a dry, ventilated place.
5 Fruit, vegetables and sorghum – a type of cereal prone to fungal infestation if not preserved – are then placed in the smaller pot, which is covered with a damp cloth.
6 In the heat, the water contained in the sand evaporates towards the outer surface of the larger pot. This evaporation brings about a drop in temperature of several degrees, cooling the inner pot and extending the shelf life of the perishable food inside.
How will you protect your savings and yourself in the event of an Disaster ? This just-released PDF guide Surviving and Thriving During any Disaster will show you exactly how. Click here to download the PDF now.
- The zeer pot will eventually accumulate mineral build-up. Use hot water and a sponge, or perhaps a bit of lemon juice to dissolve away the minerals that crust up on the outside of the zeer pot.
- The zeer pot will not be as cold as a refrigerator; it will be cool, and it will keep your food cool, but it will not chill a hot container of food down to safe temperatures.
- The zeer pot needs a breeze to cool. If you have a good breeze all the time, or perhaps a small fan powered by a solar panel, the pot can get quite cold. Imagine that chill you get when you step out of a pool when the wind is blowing. Now imagine that going on all day. That’s what the pot feels with a constant breeze.
- High humidity will result in reduced performance. However, a friend of mine who used a zeer pot in a hot humid part of Africa told me that it still worked “shockingly well”, so it might just work. But keep it in the shade, with a breeze.
- Zeer pots actually perform better than refrigerators for many vegetables; vegetables wilt in the refrigerator because the condensation on the cooling tubes dries out the air. Refrigerators blow a lot of air over a little chilling surface that is really cold, causing the air to dry out. In contrast, the air in the zeer pot is chilled over a much larger surface that is only a little bit colder. This minimizes condensation; also, since the surface inside the pot will be moist terra cotta, the air inside will have as much moisture as possible, which keeps vegetables crisp in spite of not being as cold as a refrigerator.
The zeer pot is a greener option only if you use it according to the following rule:
- These things can evaporate a couple gallons of water a day if you have a good breeze, especially if the weather is dry and warm. If you multiply this water consumption by several zeer pots, this can be a considerable water consuming appliance. I don’t intend to unleash upon the world a device that wastes water in lieu of using electricity, especially in California, where we are experiencing a drought; I expect that everyone who uses these zeer pots to use a bucket to catch the gallons of water that you would normally waste while waiting for the shower to warm up, and to recover this water for the zeer pot. That way, you’re saving electricity without using any additional water. Or, go ultra-sustainable and use captured rain water.
First of all, The Lost Ways would convince readers that the natural disasters are inevitable. It will give them an excellent insight about the disasters that could take place in the future. Therefore, it is extremely important for all the human beings to stay prepared to face a disaster, which could happen at any given point of time. In the second part of this book, the readers will be able to discover the lessons learned by humanity when they encountered disasters in the past. Every disaster teaches us a lesson, and it is better to have a clear understanding of these lessons as they can be helpful in the future.
SOURCE : practicalaction.org
SOURCE : instructables.com
Other Survival Solutions(This are the most reliable survival books that you can find)