Introduction / Excerpt
Customers frequently ask Dell, “what is the best temperature to run your servers?” In 2009 when we first published our conclusions, we found that typical facilities would conserve the most energy when running between 75°F and 80°F (24°C and 27°C). With improvements in IT equipment design, recent analysis suggests the range may have shifted a few degrees higher, which is deserving of an update to our original paper. The original paper focused solely on compressor-based facilities.With increasing interest in economizers, this new paper will also discuss a sweet spot operating temperature, or a lack thereof, for non-compressor-based facilities.
Operating temperature is a topic that has been discussed at length in both The Green Grid and the ASHRAE (American Society for Heating, Refrigerating, and Air Conditioning Engineers) datacom technical group. ASHRAE has recently increased its recommended operating temperatures by several degrees and has also created new IT equipment classifications specifically intended for chiller-less operation.
Our initial theory was that temperature-induced increases in IT fan power might negate the facility energy advantages associated with running compressor-based cooling at a higher temperature set point. With this theory in mind, we approached our colleagues at APC (American Power Conversion) to engage in the discussion. What we found confirmed our assumption: there is a sweet spot operating temperature for compressor-based cooling in your data center.