Simulation and Optimization of Data-Center Cooling System with Naturally Cooled Reservoir Water

Owing to the transformation of data centers toward intelligent computing, the power density per cabinet has increased, leading to an increment in the proportion of cooling-energy consumption. Reducing the power-usage effectiveness (PUE) of data centers is crucial. This study proposes a cooling system that combines natural water sources with liquid-cooling technology. Considering a data center in Laibin, Guangxi as the research object, a system model is constructed to analyze the system performance under different control methods and operating conditions. Subsequently, it is compared with conventional water-cooled chiller cooling systems. The result shows that controlling the supply-air temperature through the chilled-water pump reduces energy consumption by approximately 10% energy and facilitates waste-heat utilization. Additionally, controlling the chilled water-supply temperature through the cooling water pump is more energy efficient, although the energy-saving ratio decreases as the reservoir water temperature increases. The natural water-source cooling system achieves an annual energy-saving rate of 73.5% with a cooling load factor of 0.05, which is lower than that of the conventional system. When the supply-air temperature setpoint is higher, the system energy consumption fluctuates less. Based on a comprehensive consideration, 28 ℃ is a suitable temperature. This study provides a reference for the design of green and energy-efficient data-center cooling systems.