A Study on the Energy Reduction Measures of Data Centers through Chilled Water Temperature Control and Water-Side Economizer

Abstract

The degree of integration of IT devices and consumption of cooling energy are consistently increasing owing to developments in the data center industry. Hence, to ensure the smooth operation and fault prevention of IT devices, the energy consumption of cooling systems has increased, leading to active research on improvements in cooling system performance for reducing energy consumption. This study examines the reduction in cooling energy consumption using a simulation by applying chilled water control and a water-side economizer (WSE) system to enhance the cooling system efficiency. The simulation results showed that the energy consumption was reduced by 1.8% when the chilled water temperature was set to 11 °C in a conventional system and by up to 19.6% when WSE was also applied. Furthermore, when the changes in chilled water temperature were applied for efficient operation of WSE, the energy consumption was reduced by up to 30.1% compared to that in conventional energy systems.

Research on a Plan of Free Cooling Operation Control for the Efficiency Improvement of a Water-Side Economizer

“…Accordingly, the maximum heat transfer of the coil is determined by the minimum heat capacity and temperature difference between the air and the chilled water supplied to the coil, according to Equation (8).…”

“…Particularly, to reduce cooling energy in data centers, which experience summer-level cooling loads even in winter, a WSE is applied to introduce cold outside air during winter and intermediate seasons to cool the room. The energy savings from applying a WSE range from approximately 10% to 47% [6][7][8][9]. Free cooling with a WSE can significantly reduce energy usage by replacing the role of the chiller with a heat exchanger during winter.…”