Research and Technologies for next-generation high-temperature data centers – State-of-the-arts and future perspectives

Data centers have attracted increasing attention worldwide over the last decades due to their high energy consumption. Cooling accounts for about 30–40% of the total energy consumption of data centers. High-temperature data centers could save large amounts of cooling energy by changing their cooling mechanism. More effective use of “free cooling” is the basic and effective means for high-temperature data centers to reduce cooling energy consumption. It is possible to build chiller-less or even chiller-free data centers. They require less capital investment for cooling and allow more hours of “free cooling”. However, a few essential concerns need to be addressed before the wide application of high-temperature data centers, particularly the technical bottlenecks and the reliability and performance of servers and IT equipment. Though many reviews on data centers exist in the existing research, a systematic review of high-temperature data centers, particularly on the above essential concerns, is still unavailable. This paper is intended to fill in these gaps and provide a comprehensive review of these critical aspects. The main benefits and the major bottlenecks for implementing high-temperature data centers as well as the existing efforts and latest technologies to tackle the bottlenecks are categorized and analyzed systematically. In addition, a through review of the main temperature-sensitive IT components (e.g., hard disk drives and CPU) is done, and their current states and potential solutions are analyzed. Finally, the paper elaborates on future perspectives for the development and applications of the high-temperature data center.