Evaporative Cooling is remarkably energy efficient
Evaporative cooling takes place when water molecules evaporate into the air by which water changes from a liquid to a gas state. In order for water to change from a liquid to a gas it requires a certain amount of energy or heat.
This energy or heat is automatically taken from the surrounding air and as a result the air temperature becomes cooler. In effect the more water you evaporate the more cooling can be achieved. Nature’s method of cooling can be most easily recognised as RAIN but how else can we harness the cooling capabilities of water?
Spraying systems - Here water is sprayed through nozzles at different pressures. The water particles become smaller and evaporate as they fall to the ground. Porous materials with large surface areas - Water is run over a surface that facilitates the evaporation process. Often forced air is used to enhance this process. Ultra-sonic evaporation - This method shatters water into super fine particles through ultra-sonic vibrations.
Compared to air-conditioning, evaporative cooling consumes far less electricity. This is especially useful when looking to cool large spaces that are enclosed or open to the elements. In many industrial processes water based cooling is the only practical method to achieve cooling since water is comparatively cheap and abundant next to electricity.
Water is cheap and plentiful and little water is needed to achieve effective cooling. Large scale cooling can be achieved outdoors. Air is humidified during the evaporation process which improves the air quality. Increased humidity will remove dust from the air and make the air safer to breathe.
Each specific application will dictate the required equipment. Key points to consider will be the following; Size of the area to be cooled; is the area open or enclosed; if the area is open, is it exposed to regular wind? If yes, suitable wind breakers must be implemented; if the area is enclosed, forced ventilation will be required; is the structure suited to evaporative cooling; what is the desired end air temperature that will be required?
There are a large amount of manufacturers worldwide who supply and install cooling equipment. Most companies will either specialise in either air-conditioning or evaporative cooling however some will provide both.
The internet is a useful information source to find a local supplier or alternatively a local business directory can be consulted. Look under “cooling equipment” or “air-conditioning” headings. Be sure to ask as many questions as possible and request to visit a location where the same equipment you are looking to purchase has been installed. This will enable you to determine if evaporative cooling will be suitable for your requirements.
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