Energy Efficient HPC Working Group

Liquid Cooling (Wx)

Liquid cooling is key to reducing energy consumption for this generation of supercomputers and remains on the roadmap for the foreseeable future. This is because the heat capacity of liquids is orders of magnitude larger than that of air.  Once heat has been transferred to a liquid, it can be removed from the datacenter efficiently.  The Energy Efficient HPC Working Group  (EE HPC WG) has seen the transition from air to liquid cooling as an opportunity to work collectively to set guidelines for facilitating the energy efficiency of liquid-cooled High Performance Computing (HPC) facilities and systems.


The EE HPC WG has worked with the American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE) to develop guidelines for warmer liquid-cooling temperatures in order to standardize facility and HPC equipment, and provide more opportunity for reuse of waste heat.  The vision is to encourage non-compressor-based cooling, to facilitate heat re-use, and thereby build solutions that are more energy-efficient, less carbon intensive and more cost effective than their air-cooled predecessors.  The guidelines are commonly referred to as "Wx" and can be found in the ASHRAE publication below.


Further references:


Liquid Cooling Guidelines for Datacom Equipment Centers



Coles H, Ellsworth M, Martinez D., et. al., “Hot for Warm Water Cooling”. SC11 International Conference for High Performance Computing, Networking and Storage. 2011 November 16. [Internet]. (c2011-2013).

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Liquid Cooling (Wx)