Monday, May 16, 2011
New ASHRAE Temp/Humidity Guidelines
There are even guidelines for lower humidity level if certain procedures are followed.
--kb
P.S. Thanks to Pasi Vaananen for the heads-up.
Wednesday, April 29, 2009
Human Side of Higher Data Center Temperatures
One approach is to adopt a "fail in place" model where technicians never go into a production facility, but even Google has technicians adding and replacing individual servers in their containerized data centers.
Other approaches to consider:
- Localized spot cooling. A very small air conditioner could take the edge off the area in front of a rack.
- Perform service operations at night or when it's reasonably cool.
This last suggestion may seem too simplistic at first, but it's actually quite practical. In a facility with sufficient redundancy to ensure high availability, server replacement should be able to wait up to 24 hours. Operating a data center at consistently high temperatures will end up increasing power consumption in the IT equipment. It only makes sense to use higher temperatures in a data center when using optimizers to eliminate or substantially reduce HVAC CapEx and OpEx costs.
If a data center is using economizers, the temperature in the data center should drop when the outside temperature drops. Even in relatively warm areas during summer months, there are substantial times each day where the temperature drops to reasonable levels in which technicians can comfortably work.
--kb
Saturday, January 31, 2009
Temperature and Climate Data Around the World
There's a nifty utility available from UCLA called Climate Consultant (see

http://www.aud.ucla.edu/energy-design-tools/tools/Climate4.exe or
http://www2.aud.ucla.edu/energy-design-tools/). This software allows you to draw
psychrometric charts, plot average/min/max temperatures, etc. for any location for which you have the proper type of weather file. For example, the graphic at the right shows a psychrometric chart for Hillsboro, Oregon.
Not only is this utility free, you can get weather data for many locations for free. The U.S. Department of Energy (DoE) maintains weather data for over a thousand locations around the world, including most airports at http://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data.cfm. For example, http://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data3.cfm/region=4_north_and_central_america_wmo_region_4/country=1_usa/cname=USA#OR provides data for several sites in Oregon. Just save the .EPW file to your local hard disk, and you're good to go.
Enjoy,
--kb
P.S. Thanks to Pasi Vaananen for the pointer to this tool.