"Clearly, within the data center, there is a need to measure so you can then control," said Larry Vertal, a senior strategist at Advanced Micro Devices and a Green Grid representative. "Right now, without the application of any measurements, it is hard for a data center operator to determine which button they should push to create differences." Fear is also a problem. "Sometimes people think it is very difficult to measure efficiency and are afraid that a rating system will show that they aren't as good as they thought they were," Belady said.

As part of its efforts to ease these fears and get data centers moving in the right direction, the Green Grid Metrics and Measurement Work Group—composed of 21 member companies—has created the Data Center infrastructure Efficiency metric and the Power Usage Effectiveness metric, which measure energy efficiency in the data center. 

In the long term, the Green Grid is developing efficiency metrics for all major power-consuming subsystems in the data center. "We are spending energy on making sure that we look at all the ratings systems and metrics as a global effort," Belady said.

Hailey Lynne McKeefry is a freelance writer based in Belmont, Calif. She can be reached at hailey@professionalink.com.