The Green Grid, best known for having created the Power Usage Effectiveness (PUE) metric, has developed what it calls a new multi-metric view that provides a broader understanding of data center cooling performance.

The industry body aimed at improving data center efficiency said that the ’Performance Indicator’ (PI) will allow facility operators to better predict the outcome of potential changes. PI is an adaption of the ACE metric, created by Future Facilities, and is making its first appearance outside Green Grid events at DatacenterDynamics’ Webscale event in San Jose this week.

Performance anxiety

The Green Grid cites criticism over PUE’s inability to take into account other aspects of performance as a reason for creating the new ‘multi-metric’ solution. The Performance Indicator brings together the PUE ratio, IT Thermal Conformance and IT Thermal Resilience.

Although PUE has succeeded because of its simplicity, th etime is right for a more nuanced and multi-dimensional metric, Future Facilities director Sherman Ikemoto said to DCD at the Webscale event: “PUE is useful, but has limitations,” he said.

Sets of cooling towers in data center building
Cooling towers in data center building – Thinkstock / willcao91

“Rather than completely build the Performance Indicator metric from the ground-up, the metric has been created to address the most critical aspects of a data center’s cooling performance,” said Roel Castelein, The Green Grid EMEA marketing chair.

“While PUE is an effective step forward to measure current-day energy efficiency, in order to establish a more complete view of facility cooling, the requirement to calculate cooling effectiveness and the data centre’s future thermal state is also critical.”

But just as PUE fails to provide a complete view of data center performance, any existing combination of metrics could soon become obsolete.

“The real strength in the Performance Indicator for data center operators is its ability to be easily scalable and accommodate additional new metrics in the future, as they are defined,” Castelein argued.

“This will ultimately increase the scope of productivity for data center organizations, as well as preventing the criteria from becoming out-dated for modern data centre demands.”

Mark Seymour, CTO at Future Facilities and chair of the white paper, added: “The Performance Indicator allows these critical business decisions to be made based on scientific assessment, rather than relying on historic PUE and guesswork.”