Energy-Efficient Computing and Data Centers

3Cooling the Data Center

3.1. System cooling technologies used

Cooling a “hot” device requires a “cold” fluid to capture its heat and transport it to the data center infrastructure, which will carry it away. In Chapter 2, we discussed how to extract the heat from an air-cooled device. In this Chapter 3, we discuss how the heat is transported and carried away by the data center cooling infrastructure and alternative cooling technologies.

Practically all the electrical power required in a data center is converted into heat, which has to be removed by a proper cooling system. The most suitable cooling solution should be designed, depending on the design criteria, to obtain a high energy efficiency, low cost and reliability. A cooling system should be designed to cover the worst-case scenario, although most servers generally work at much lower capacity than 100%. The control and prediction of temperature rising during a utility power outage is an important aspect for cooling system design. Air-cooled systems represent the backbone of data center cooling systems; they are evolving over the years to cope with the advance in the IT equipment. The evolution of air-cooled system is going toward localized cooling units and physical separation of the airstream within the data center in order to support the rising power densities. On the other hand, liquid-cooled systems are becoming promising and emergent solutions for cooling high power density data centers. Today, the IT equipment ...