PUE Harmonized
Okay so PUE may just be one number divided by another, about as simple a mathematical equation as you can get but since the Green Grid first announced PUE you wouldn't believe how much confusion and outright cheating on the calculation there has been.....or perhaps you would because you're in the data center industry and have seen it!
Well, it may or may not come as a surprise to you that for the past 18 months an international team of government representatives have been working on harmonizing data center energy efficiency metrics to ensure global consistency of definition and use.
The team consists of representatives from the EU, USA and Japan and is populated by two individuals from each of the following organisations: US DoE, US EPA, Lawrence Berkeley National Laboratories, European Commission Joint Research Center, Japanese GreenIT Promotions Council, the Japanese Ministry of Economy Trade and Industry and the Green Grid acting as facilitators.
The European representatives are Paolo Bertoldi and myself both representing the European Policy Action that is the EU Code of Conduct for Data Centers.
The group started with PUE but ultimately we're working our way towards metrics that describe productivity of ICT and data centers. Those that dabble in energy efficiency and productivity metrics will know that while PUE very simply and elegantly describes the energy transfer efficiency of the mechanical and electrical elements of a data center, the complexity within the ICT layer has so far meant that a true productivity metric has eluded us.
The Global Metrics Harmonization Task Force as the group is known, meets by teleconference twice a month and then face to face every 6-9 months. February 2011 saw the achievement of a milestone during the Tokyo face to face meeting.
The group concluded work and an agreement on PUE. The recently published communication of this agreement includes links to the detail of the work which include guidance on PUE measurement boundaries, measuring PUE in a mixed use building, how to calculate PUE for source energies other than electricity and guidance around how to account for energy reuse and on-site generation.
Now that PUE is finally out of the way the group will turn its focus on to other metrics such as the productivity metrics (and proxies) such as the DPPE metric and sub-metrics from the Japanese, the productivity proxy work of the Green Grid and others such as CUE, ERE, ERF and OGC.
So in summary.....standby for more harmonized metrics from the team over the next 12 months!