Large HVAC systems almost always incorporate water-cooled chillers to improve efficiency. But, these systems can be made even more efficient if cooling towers are selected on the basis of minimizing fan motor horsepower rather than just minimizing first cost. By selecting a larger tower, there is more heat transfer surface available and, thus, the airflow required by the tower is significantly reduced. This reduces fan motor energy consumption and the tower is much quieter…making it a better neighbor!
New Hanover County Schools just brought online two new replacement 500-ton cooling towers selected by Stanford White. Total fan horsepower was reduced from 100 hp to 40 hp…a 60% savings…and the condenser water approach temperature was reduced from 7ºF to 4ºF, further improving cooling energy efficiency. While the tower “boxes” are 50% larger than the original towers, the existing foundations were reused since the increased volume was created simplyby making the towers taller.