'The outcome of the meeting is an agreement to three guiding principles for measuring energy efficiency in data centers at the present time. These guiding principles are meant to help the industry have a common understanding of energy efficiency metrics that can generate dialogue to improve data center efficiencies and reduce energy consumption. Each of the participating organizations has agreed to promote these guiding principals to their members and stakeholders in an effort to bring uniformity to the measurement of data center energy efficiency, while the dialogue continues to advance existing metrics. "
The organizations represented were the 7x24 Exchange, ASHRAE, The Green Grid, Silicon Valley Leadership Group, U.S. Department of Energy's Save Energy Now and Federal Energy Management Programs, U.S. Environmental Protection Agency's ENERGY STAR Program, U.S. Green Building Council, and Uptime Institute.
The three guiding principles are:
Power Usage Effectiveness (PUE) using source energy consumption is the preferred energy efficiency metric for data centers. PUE is a measurement of the total energy of the data center divided by the IT energy consumption.
When calculating PUE, IT energy consumption should, at a minimum, be measured at the output of the uninterruptible power supply (UPS). However, the industry should progressively improve measurement capabilities over time so that measurement of IT energy consumption directly at the IT load (i.e. servers) becomes the common practice.
For a dedicated data center, the total energy in the PUE equation will include all energy sources at the point of utility handoff to the data center owner or operator. For a data center in a mixed?use building, the total energy will be all energy required to operate the data center, similar to a dedicated data center, and should include IT energy, cooling, lighting, and support infrastructure for the data center operations.
The announcement further stated:
'This guidance is meant to help the industry have a common understanding of energy efficiency metrics that can generate dialogue to improve data center efficiencies and reduce energy consumption. Member organizations are committed to applying and promoting these guidelines to their programs.
This appears to be an effort by these organizations to try to clarify the expected direction of upcoming EPA Energy Star for Data Centers program standards, which is scheduled to be finalized in April. There were some earlier meetings in September and November of 2009 by the EPA working group that were somewhat ambiguous about which metric was going to be used for the certification process and where and how the measurements were going to be taken.
There is still some ambiguity in this new announcement since they seem to be using the term PUE (Power Usage Effectiveness) yet also using the word 'energy." (Energy is power over time, i.e., KW vs KWH.)
Nonetheless, I believe that 2010 will bring about a large increase in data center energy efficiency awareness and prompt many organizations to start implementing some form of energy monitoring and management. The underlying issue, is that in many cases (as the EPA study found), very few data centers have any form of energy monitoring for the IT load, other than the output of the UPS, and even fewer have input power measurement capabilities, other than the monthly utility bill.
So attention all manufacturers of energy monitoring systems -- start your sales force.