October • 2013
Additionally, the performance of the cooling tower can adversely effect the entire HVAC system. An inefficient cooling tower may not provide appropriately cooled condensing water which results in an under performing chiller. Therefore, it pays to look at every component in an air conditioning system to make sure that each one is saving as much energy as possible.
Cooling tower fans are generally either on or off. Variable Frequency Drives (VFD), however, can adjust AC motor speed and torque to maximize performance under specific conditions. In an HVAC system, for instance, the typical fan will come on when the temperature reaches a pre-determined range and will continue to operate until the temperature falls below or rises above that level. Using a VFD on a cooling tower fan motor can improve performance and boost efficiency.
VFDs take a specified approach by controlling the fan motor's speed and torque to maintain an ambient temperature. The fan motor does not always need to offer its full force and the VFD will adjust the speed so that it only does the work necessary. This makes the cooling tower more efficient and helps owners save money by reducing energy consumption.
According to the U.S. Department of Energy, US industries could save about 18% of the energy they consume just by switching to technologies like Variable Frequency Drive use. That not only means big savings for business, but decreased demand makes energy less expensive for everyone.
Water treatment programs are designed to protect three concerns of the Cooling Tower.
The first two requirements help to ensure energy efficiency and longevity of the cooling system, while the third ensures safe operation.
Cooling towers also collect airborne dirt and debris buildup over time. To control this, the cooling tower should be located to minimize contaminant introduction and a proper blowdown rate should be upheld. Sidestream filters are helpful at successfully removing dirt and debris from the tower water. Cleaner tower water makes water treatment procedures more effective while keeping the cooling loop clean, saving energy, reducing maintenance, and improving dependability of the whole cooling system.