Experimental investigation and application analysis on an integrated system of free cooling and heat recovery for data centers

Rapid growth of data centers has caused a huge increase in energy consumption. Utilizing natural cold resources and harvesting waste heat are two promising ways to reduce the total power consumption of data centers. This paper proposes an integrated system of free cooling and heat recovery. The system has four working modes: mechanical cooling, mechanical heat recovery, pump free cooling and pump heat recovery. Experimental results show that pump free cooling mode can achieve an energy efficiency ratio of 7.99 when outdoor temperature is 2 ?C, and different modes can be switched smoothly. The applicability of this system has been evaluated in five different cities in China. The results show that annual average energy efficiency ratio can reach 6.18 and free cooling time can take up as high as 72.9% during operation in Xining. The system can harvest the most heat in Harbin, 7930.96 kW.h per year, while the least in Guangdong, 645.31 kW.h per year. This means that this new system has relatively great application prospects in northern cold cities of China, while is moderately limited in southern cities.

Automated summary

This paper proposes an integrated system of free cooling and heat recovery to reduce the energy consumption of data centers. Experimental results show that the system can switch smoothly between different modes and has good applicability in various cities in China, especially in northern cold cities.