Zero Energy Cool Chamber: Brewing in Summer made easy By Dilip Maheshwari

I am living in  Jaipur,Rajasthan and started brewing two month ago.
This blog helped me alot in understanding various concepts and facts of Brewing and my first batch went well as the temperature in February was favourable.

Now its April here and Temperature reached 35 plus and soon it will touch 40 degree which is almost impossible to brew without help of a refrigerator.

I thought to ferment my wort in a tank like double wall structure called "Zero Energy Cool Chamber"
It is generally made by farmers on their field to store vegetables and fruits in Summer to increase
their longevity for market and it improves keeping condition.
A few facts about this structure:

Zero Energy Cool Chamber

Principle: It works on the Principle of Evaporation,
Material used: for making a sizze to ferment 2 carboy of 5 gallons we need around 250 bricks, well baked and new, 4 bags of sand( bajri used for construction)
Skills: Does not any special skills to make one can make easily at home
Selection of place:It should be made a shaded place, well ventilated and away from direct sunlight.

If you are making this in garden you need a shade atleaste 8 feet high so you can stand under that and work.
Please Decide size for the appropriately you need accourding to your use.
Keep in mind the it should be more wide than high to work properly.
After deciding  keep the bricks over you size in flat manner so you can keep you fermentor on it.

Start making a wall around your required area as high as your fermenter is covered

Staple staking of Bricks
Bricks should be kept staple styles, so that they can be fixed without using cement.
When the inner structure is made now its time to make another structure all round outside with the gap/ Cavity of 7.5 cm approx and raise to same height of inner sturcture.

Now clean the sand and remove all kind of stone, organic matter plants etc.
make it wet with water and fill this cavity on all four sides with it.
You can also use a stick to press the sand as much you can.
After filling the wet sand also spread a thin layer inside floor where you going to keep your fermenter.

Water the structure and sand gently so it can start evaporating and can reduce the temperature.

To cover the structure you can use a wet jute cloth, straw mat, any natural material like thatches etc.

You can water this structure in the morning and in the evening daily and can note the temperature inside.
If you busy and can not do it,take a small over head plastic tank and attach the pipe and do some holes it waters automatically.

The structure is efficient to keep the temperature 12 to 15 degree below the ambient temperature.
Can also be developed in spare, upstair room with good ventilation.

The life is this structure is is three years and it needs to be sanitized thrice in a month with bleach water, star san etc.
Please feel free to ask questions.
Close up-Inside
Accomodating two carboys and some bottle for carbonation


  1. Great post Dilip.

    Question -
    Why do you need to Sanitize this thrice a month ?
    I am asking because you are using closed fermentation, and the risk of infection is very little.

    1. Since we are using the sand from open sources, there may be chances of unwanted microbes in it.
      Need of sanitization arises due to more humid environment inside the chamber and incase the off tube or carboy cap is leaky there are chances of contamination.
      This practice can be reduced to once in a month.
      For sanitization we can sprinkle used santizers left after cleaning the bottles and equipemnts.

  2. Fantastic idea. Bit high maintenance wrt sanitisation but great idea nevertheless.

    1. You can skip sanitization almost or once in a month.
      No sanitization needed if you are using air lock.

  3. Hi Dilip, my name is Taylor Graham and I am also living in Jaipur starting to home brew. I would love to exchange tips sometime! Very cool idea. Maybe I will try this when it get's hot. Starting an IPA recipe soon!


Please mention your email ID, if you have any queries, so I can contact you.