How Higher Chilled Water Temperature Can Improve Data Center Cooling System Efficiency

Alternative data center cooling approaches such as indirect air economization are calling into question the economic justification for using traditional chilled water cooling in new data centers, especially those in mild climates. This paper describes some innovative approaches to chilled water cooling, where the chiller is used only to boost cooling capacity on the hottest days. A capex and opex analysis describes how these approaches can save 41%-64% opex, with 13% increase in capex with assumption of using the same chiller. We also discuss the design considerations for these new technologies.