Optimal setting parameters of cooling system under different climate zones for data center energy efficiency

The high rates of electricity consumption in data centers become a worldwide concern. Water-side free cooling is an effective solution to reduce the energy consumed by the data center's cooling system. However, the water-side free cooling system is not well planned, and the free cooling utilization rate is low in different climate zone. Moreover, the effects of local climatic conditions on the optimal setting parameters have not been researched. In this study, the optimal setting in chilled water supply temperature, temperature difference, and chilled water return temperature is analyzed to enhance the efficiency of the free cooling system. We observed that the optimal setting could reduce annual energy consumption by 23.5%-60.8% in various climate zones and has substantial energy-saving potential in the subtropical highland climate zone. The results show that the optimal setting parameters are highly affected by the annual accumulative wet-bulb temperature distribution. Furthermore, considering a monthly analysis of these enhanced parameters, we proposed a dual-working condition cooling system for the data center's future construction. This research work guides the design of such cooling systems in various climate zones