WP#50 - Data Center Efficiency and IT Equipment Reliability at Wider Operating Temperature and Humidity Ranges

Overview

The Green Grid's white paper number 50 is dated 23 October 2012 and was edited by Steve Strutt of IBM; its authors also include Chris Kelley, Harkeeret Singh and Vic Smith. Access requires signing in with a free Green Grid account, and copyright rests with the organisation. This record rests only on the abstract on the library's public landing page; the full text of the paper has not been read.

The paper examines how temperature and humidity affect IT reliability and energy use as the operating range widens. It draws on ASHRAE data that had recently been published at the time. As an approach, it challenges common misconceptions about higher operating temperatures and tests the hypothesis that wider ranges can improve efficiency without a substantive impact on reliability or availability.

The point the abstract stresses is that the cooling-energy gain from raising temperature has to be weighed together with equipment reliability. This means facility operators raising set points should look not only at energy savings but also at the possible reliability effect. The abstract gives no numerical results, so no figures from the paper's findings are reproduced here.

The limit of the record is that it holds only abstract-level information. Which temperature and humidity bands the paper evaluated, what failure-rate assumptions it used and under which conditions its conclusions hold are not known here. The ASHRAE Thermal Guidelines x-factor is the related concept. The source should be used as a contextual reference in set point discussions, and the full text consulted for numerical decisions.

Key points

1. Dated 23 October 2012; editor Steve Strutt (IBM).
2. Looks at temperature and humidity effects on IT reliability and energy usage.
3. Uses recently published ASHRAE data.
4. Addresses misconceptions about higher operating temperatures.
5. Explores whether a wider range can improve efficiency without substantive reliability impact.
6. Access needs a free Green Grid account; the record rests on the landing page only.

Using it in design

• When users raise supply air above the ASHRAE recommended range, show both the cooling-energy saving and a reliability note (ASHRAE x-factor) instead of a hard error.
• Report energy gain and reliability effect together in set point decisions.
• Verify any numerical values from the full text before using the paper's findings.

Who should read it

Data center designers and operations engineers who set cooling set points and operating ranges.

Related standards

• ASHRAE Thermal Guidelines (x-factor)

Publication details

Authors

Steve Strutt; Chris Kelley; Harkeeret Singh; Vic Smith

Publisher

The Green Grid

Year

2012

Document number

WP 50

Document language

English

Source type

Industry body

Access

Citation only

Licence

Copyright retained; citation only — the publisher’s terms apply to the original document

Citation