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Water cooler

Simple wooden charcoal water cooler – easy to build – https://ifdc.org/2017/05/05/charcoal-is-cool/

Building a brick water cooler

Building an evaporative water cooler using bricks and double walls with charcoal, a shading sink roof, and a chimney is a fascinating project. This type of cooler is commonly used on Southern African farms to help keep produce cold during hot weather. Let me break it down into simple steps for you:

Step 1: Gather Materials

You’ll need the following materials:

  • Bricks
  • Cement
  • Charcoal (small pieces, like those used for braais)
  • Wooden boards or other materials for the roof
  • Metal sheet or other material for the chimney
  • Water source

Step 2: Building the Outer Wall

First, decide on the size and shape of your water cooler. It could be a small room or just a box-like structure. Start by laying the bricks in a rectangular or square shape to create the outer wall. Use cement to hold the bricks together and build up the walls to your desired height (about waist-height should be good enough, but room height is ideal)

Step 3: Building the Inner Wall and Charcoal Filling

Inside the outer walls, leave a gap of around 5cm and build another inner wall using bricks. This will create a double-wall structure. The gap between the walls will be filled with charcoal. Space the bricks so that there is about a 3cm gap through which the air can flow. Once the inner wall is built, carefully pour the charcoal pieces into the gap between the walls. The charcoal acts as a natural cooling agent when wet, helping to keep the air inside the cooler cold through evaporation.

Step 4: The Shading Sink Roof

Now, you’ll need to create a roof for your water cooler. A shading sink roof is a great option for keeping the structure shaded and cool. For this, you can use wooden slats or other materials that are easy to work with. The roof should be slanted, so it helps drain rainwater away from the cooler.

Step 5: Building the Chimney

On the top of the cooler, add a chimney using a metal pipe or another suitable material. The chimney will help to pull hot air out of the cooler, promoting better airflow. Make sure the chimney extends above the roof so that it can effectively remove the hot air from inside the cooler. If you paint it black it will work even better as it heats the air inside the chimney which will then rise faster to pull more air through the cooler.

Step 6: Adding Water

To use the evaporative cooling effect, you’ll need to add water to the charcoal inside the walls of the cooler. You can have a small tank or bucket of water on top of the cooler and a few irrigation pipes, or just connect it to your pressured supply if you have. As the hot air from outside passes through the wet charcoal-filled gap between the walls, it will cool down due to the water evaporation.

Step 7: Maintenance

Put water on the charcoal in the morning and early afternoon. Check that your charcoal does not dry out. Also, keep an eye on the charcoal to ensure it remains effective for cooling. Over time, you may need to add to the charcoal if it loses its cooling properties.

That’s it! With these steps, you’ll have a simple evaporative water cooler using bricks, charcoal-filled double walls, a shading sink roof, and a chimney.

A brick water cooler on a Namibian farm under construction
The same cooler from the front with the door shown. The chimney is still to be made.

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