Improving Data Center Energy Efficiency With Advanced Thermal Management

• Published in: IEEE transactions on components, packaging, and manufacturing technology (2011) packaging, and manufacturing technology (2011), 2017-08, Vol.7 (8), p.1228-1239
• Main Authors: Chainer, Timothy J., Schultz, Mark D., Parida, Pritish R., Gaynes, Michael A.
• Format: Article
• Language: English
• Subjects: 3-D; Chips; Computational efficiency; Computer simulation; Computers; Computing time; Cooling; Cooling systems; data center cooling; Data centers; Electronic packaging thermal management; electronics cooling; electronics packaging; Energy consumption; Energy conversion efficiency; Energy efficiency; Energy management; Engineering; Fans; Interconnections; Liquid cooling; Materials Science; Microprocessors; Power management; Reduction; Refrigeration; Servers; Stacks; Temperature distribution; Test vehicles; Thermal management; thermal management of electronics; two-phase cooling; Warm water; Water heating
• ISSN: 2156-3950; 2156-3985
• DOI: 10.1109/TCPMT.2017.2661700

Experimental investigation of data center cooling and computational energy efficiency improvement through advanced thermal management was performed. A chiller-less data center liquid cooling system was developed that transfers the heat generated from computer systems to the outdoor ambient environment while eliminating the need for energy-intensive vapor-compression refrigeration. This liquid cooling system utilizes a direct-attach cold-plate approach that enables the use of warm water at temperature a few degrees above outdoor ambient to achieve lower chip junction temperatures than refrigerated air. Using this approach, we demonstrated a cooling energy reduction by over 90% and computational energy reduction of up to 14% compared to traditional refrigerated air cooled data centers. To enable future computational efficiency improvements through high-density 3-D-chip stacking, we developed a 3-D compatible chip-embedded two-phase liquid cooling technology where a dielectric coolant is pumped through microscale cavities to provide thermal management of chips within the stack. In two-phase cooling, liquid is converted to vapor, which increases the capacity to remove heat, while the dielectric fluid enables integration with chip electrical interconnects. A test vehicle simulating an eight-core microprocessor was fabricated with embedded cooling channels. Results demonstrate that this volumetrically efficient cooling solution compatible with 3-D chip stacks can manage three times the core power density of today's high-power processor while maintaining the device temperature well within limits.