;This study primarily analyzes the energy-saving effectiveness of the water side of air-conditioning system in a semiconductor packaging and testing plant. Computer was used to calculate the energy consumption, to maintain optimized operating mode, to analyze the energy-saving effectiveness, and to understand the energy consumption of the chiller, chilled water pump, cooling water pump, and cooling tower fan operating under various weather conditions and air-conditioning load factors. Mathematical model was used in this study to calculate the optimized power consumption of the chiller, chilled water pumps, cooling water pumps, and cooling towers. Algorithms and frequency converters were used to control each component so that the overall power consumption was kept to a minimum, and to ensure optimal combined operations appropriate for a given load condition. A long-term energy efficiency verification process was undertaken to ensure that results of calculations were accurate and were appropriate for use as assessments of electricity savings and investment decisions for energy-saving projects. Study data showed that from August 2013 to December 2013, the refrigeration tonnage of the water side air-conditioning system decreased as outside air wet bulb temperature decreased. However, for December, the decrease in tonnage was not in direct proportion of the outside air wet bulb temperature. Analysis of the overall energy-saving efficiency showed an average energy-saving rate of 17.75 %, lowest in August (during summer) at 11.58 %, and highest in December (during winter) at 20.49 %. During summer, the energy consumed by the chiller was at the highest; affecting the overall energy-efficiency performance. This proved that the chiller′s power consumption load is affected by the outside air wet bulb temperature. At very high outside air wet bulb temperature, Cooling towers can not further reduce the cooling water temperature of 32 ℃ situation; thereby affecting the operation of the power-saving mode.
