Green IT: Forming a Global Consensus

This week, The Green Grid achieved an important milestone in forging an agreement between U.S., European and Japanese energy regulators on a common framework to gauge data center efficiency. Although the system relies heavily on the Power Usage Effectiveness (PUE) metric in its calculations, which some observers say provides an incomplete assessment of overall energy efficiency, Green Grid members like IBM's Tom Brey point out that this is only the beginning. With the world's leading economies at least functioning under a common understanding, the window is open for additional measurement techniques.

Arthur Cole spoke with Tom Brey, board member/secretary, The Green Grid, and senior technical staff member, IBM.

Cole: It looks like The Green Grid has garnered a measure of international consensus on data center efficiency. What are some of the practical ways this agreement will enable enterprises to lower energy costs?

Brey: Energy regulators and data center practitioners, like many other professions, like to standardize both the methodology and terminology of the day-to-day problems they face. The Green Grid has put forth a set of metrics which allow enterprises around the world to focus on a set of measurements that gives users a broad view at just how well their data centers are performing with respect to energy efficiency.

Cole: There is a growing chorus of voices who argue that the PUE should not be the primary factor in determining efficiency. Do you think there's room for additional measurements to gauge overall efficiency?

Brey: Of course. Energy efficiency is a journey and we simply started with an easy-to-understand ratio of energy reaching your IT equipment vs. total energy in your data center in order to focus on infrastructure inefficiencies. This got the industry moving in the right direction. The Green Grid members continue to work on developing new metrics and best practices that will expose other areas of energy efficiency. Within the IT domain, the Green Grid has white papers describing how virtualization in the IT domains can save huge amounts of energy and how a receptive power and cooling infrastructure could respond to less-than-peak energy demands, as virtualization in the short term reduces energy consumption. We have tools, for example, that can help you understand the free cooling opportunities in your geography around the globe.

Additional metrics in the IT, power and cooling domains will be key to isolating the next areas of energy improvement, along with the notion that data centers must act as a single operational unit. Many data center power, cooling and IT domains are isolated and typically set for peak loading. This makes it difficult to save additional amounts of energy since power and cooling equipment may be unaware that IT equipment may cycle down into lower energy consumption levels when IT load is at less than peak.

Cole: Much of the focus on energy efficiency naturally falls on hardware. But do you think there is a role for software as well, perhaps making more efficient use of available resources?

Brey: With respect to servers, hardware vendors and operating systems already have invested huge amounts in power management techniques that go relatively unused. The Green Grid is working with end users to understand why these features are not being enabled. These energy features promise to save double digit amounts of energy when servers are running in periods of low utilization, which is quite often. Applications running on the host are not yet energy aware. It will be exciting to see applications competing in this space.

With respect to storage, new features such as disk spin-down, deduplication, compression, automatic tiering -- all designed to optimize the use of hardware -- are becoming available. Regulatory bodies such as the U.S. EPA are becoming increasingly active in providing guidance to the industry for HW in the data center -- not only servers, storage and UPS’s but the data center itself. Perhaps this may someday include an Energy Star program for software.