ASHRAE is getting ready to finalize its third edition of TC 9.9. In advance of the release expected later this year, it has just published a 45-page white paper titled, “2011 Thermal Guidelines for Data Processing Environments– Expanded Data Center Classes and Usage Guidance,” which is now publicly available from ASHRAE.

In an unusual turn of events, the ASHRAE TC 9.9 committee announced that it has decided to disclose some of the key elements of the upcoming third edition now, rather than when it is finalized (see further coverage on p. 14 and p. 42).  

“This white paper is truly ground-breaking in that it achieves alignment between representatives of the major IT equipment manufacturers on wider environmental tolerances for IT equipment while providing guidance and a methodology for owners and operators to optimize the operating environment of their data center based on the criteria most important to their business needs,” said Don Beaty, chair of the Publications Subcommittee for TC 9.9. “In order to most quickly meet the current demands of the industry, we are using a two-step approach to introduce this important information sooner rather than later. The information in this white paper will be incorporated into the third edition of the thermal guidelines publication.”

According to an ASHRAE press release, it would seem that the recent and growing trend to increase energy efficiency by utilizing airside economizers by some high-profile internet search and social media is being recognized and will be adopted in the new guidelines.

A roadmap has been outlined to facilitate a significant increase in the operational hours during which economizer systems are able to be used, and to increase the opportunity for datacenters to become “chiller-less,” eliminating mechanical cooling systems entirely, in order to realize improved power usage effectiveness (PUE). The Green Grid created the popular PUE metric that is widely used to compare the total power to the IT power.

The major change that is introduced in the white paper is the addition of two new data center classes. The classes have been added primarily for facilities that are willing to explore the tradeoffs associated with the additional energy saving of the cooling system through increased economizer usage and what that means in terms of the impact to IT equipment attributes such as reliability, internal energy, cost, performance, contamination, etc.