Comparison between Air cooled and water cooled chiller systems

What is a Chiller?

    This device <strong>removes heat from a load and transfers</strong> it to the environment using a refrigeration system. This heat transfer device is the preferable cooling machine in power plants and other large-scale facilities.

It is simply a system consisting of ethylene + water or water reservoir and circulation components. The cooling fluid is circulated from the reservoir to the equipment undercooling.

There are also air-cooled chillers, which disperse heat-using fans. These are more recent and common in power plants. In this post, we review the difference between the two technologies, leaving the choice of which one to pick to you. ARANER would be happy to help you in the decision making process.

Water cooled chiller

Water-cooled chiller systems have a cooling tower, thus they feature higher efficiency than air-cooled chillers.
Water-cooled chillers are more efficient because they condense depending on the ambient temperature bulb temperature, which is lower than the ambient dry bulb temperature. The lower a chiller condenses, the more efficient it is.
This system has several essential components including:

• Cooling towers
• Condenser water pumps
• Make-up water pumps
• Chillers
• TES reservoirs

What are the benefits of a water-cooled chiller?
Some users may prefer these chillers because of the smaller size they occupy as compared to air-cooled chillers. These chillers also feature higher efficiency and last longer than the mentioned alternative. Those who would like the equipment to be placed indoors may find the water-cooled machine desirable.

Air cooled chiller

Where aesthetics and environmental conditions or water access restrictions exist, the air-cooled chiller may be applied. Both air-cooled and water-cooled chillers depend on an air stream as a means of heat transfer.
The difference is that the water-cooled chillers or rather the cooling towers use a humid air stream (ambient air stream + water spray) while the air-cooled chillers use a current of ambient air.
Normally water-cooled chillers are cheaper and more efficient, with the disadvantage of high water consumption.

Fig, Electrical Ratings for Water cooled HVAC units
Source: https://www.irbnet.de/daten/iconda/CIB8338.pdf

Fig, Electrical Ratings for Air cooled HVAC units
Source: https://www.irbnet.de/daten/iconda/CIB8338.pdf

Comparing the two chiller systems

Energy cost remains a major consideration in any powered equipment. Energy-saving measures are being implemented everywhere.
While the chiller has a direct impact on energy usage, there are other factors to consider. While the water-cooled chiller may be more energy-efficient, it receives stiff competition from air-cooled chiller in terms of installation cost, maintenance cost, number of equipment, and several other aspects.
Most importantly, air-cooled chillers avoid water consumption so they are the ideal alternatives in areas with water scarcity or areas with cheap energy but costly water fees.