Predictions of Airside Economization-Based Air-Cooled Data Center Environmental Burden Reduction

Abstract

Modern data centers, which consume roughly 3% of global electricity, continue to experience increased demand. Therefore, green data centers that consume less energy and have minimal environmental impact are desirable. This study examines the potential energy savings and environmental benefits of applying airside economization with evaporative cooling in air-cooled data centers in the continental U.S. A generic data center that employs a Computer Room Air Conditioning (CRAC)-based cooling system with a total IT load of 400 kW is modeled at 925 locations using the National Renewable Energy Laboratory’s (NREL’s) TMY3 database. The energy savings and environmental benefits are evaluated in terms of key data center performance metrics: Power Usage Effectiveness (PUE), Carbon Usage Effectiveness (CUE), and the recently proposed Water Scarcity Usage Effectiveness (WSUE) metric, which quantifies the holistic impact of water consumption on regional water availability. Results are aggregated and analyzed at the U.S. State level. It is found that airside economization implementation in the continental U.S. is feasible 6.57% and 21.5% of the year on average based on ASHRAE recommended and allowable envelopes, respectively. Furthermore, results indicate that carbon footprint and water scarcity footprint can be reduced by up to 16% when economization is implemented based on the ASHRAE allowable envelope.