The sustainability benefits of economization in data centers containing chilled water systems

Abstract

This study provides the first known conservative estimates of reductions in carbon and water scarcity footprints when employing economization technologies in chilled water-based data centers (DCs) in the U.S. Specifically, a generic DC that employs a Computer Room Air Handling (CRAH)-based cooling system with a total IT load of 400 kW is computationally modeled at 925 locations in the U.S. with airside and/or water-side economization. The energy savings and environmental benefits are presented in terms of key DC performance metric reductions, including Carbon Usage Effectiveness (CUE) and Water Scarcity Usage Effectiveness (WSUE). The results suggest that implementing both water-side and airside economization schemes under conditions within the ASHRAE A1 Allowable envelope reduces the mean state-averaged PUE, WUE, CUE, and WSUE by 11%, 22%, 11%, and 15%, respectively. These results highlight the environmental benefits of economization technologies and provide guidance on economization strategies.