Do you remember 1992? That was the year that Ross Perot won enough votes in the presidential election to put Bill Clinton into office.

And that was also the year in which the U.S. Environmental Protection Agency (EPA) introduced Energy Star as a voluntary partnership between government and business to reduce greenhouse gas emissions through energy efficiency. Energy Star is intended to encourage the manufacture, purchase, and use of energy-efficient products and buildings to help protect the environment.

The tremendous opportunities to save energy in data centers have been scrutinized only recently as described in the EPA’s 2007 Report to Congress in reply to Public Law 109-431. Now the EPA is eager to extend the Energy Star program to IT facilities by helping data center operators identify energy-efficient designs and technologies.

Energy Star designations will soon appear on qualified IT equipment and on data center buildings that have been benchmarked and qualified for energy performance.

In 2007, the EPA sought to identify more than 125 organizations with data centers of at least 1,000 square feet that would voluntarily provide energy usage data to help develop the Energy Star Data Center Infrastructure Rating. Participants were to collect 12 consecutive months of energy use data for its IT equipment and building.

Last month the EPA said 110 data centers had shared their energy data and submitted their data by January, the mid-point of the data collection. June 15th is the date set for the submission of final data for the program.

EPA plans to implement Energy Star for Data Centers using a PUE-based standard and then introduce a more comprehensive rating down the road.

Although PUE will be the basis for the initial Energy Star rating for data centers, the rating will be expressed on a 1-100 scale as is done for all other building types. The rating will be based on the average PUE ratio for the facility as calculated with operating data taken over a 12-month period.

PUE compares a facility’s total power usage to the amount of power used by the IT equipment, revealing how much is lost in power distribution and conversion and also cooling. An average PUE of 2.0 indicates that the IT equipment uses about half of the total power to the building.

PUE was chosen as an initial basis for evaluation because there is no consensus on a metric that would incorporate some measure of the work done by the facility. When, and if, the industry is able to reach some type of consensus in the future, EPA plans to modify the rating to be based on a comparison of energy used per unit of useful work or work output.

A similar two-phase approach is being used to develop the Energy Star for Enterprise Servers ratings, which will put a usable standard into the hands of industry while more information is gathered for improved standards.

Both the Energy Star and LEED Certifications demonstrate compliance with pre-established green criteria and set a standard for the valuation of new and existing buildings. By accepting a facility-level rating, U.S. corporations can track the energy efficiency of their data centers in a meaningful way and establish a basis for comparing the relative value of their various facilities.

Because the US Green Building Council has yet to approve LEED criteria that are relevant to data centers, the Energy Star program is more likely to become the preferred standard for data center builders and operators.

EPA planned to launch its new Energy Star Computer Server Specification Version 1.0 on May 15th, along with a Power and Performance Data Work Sheet. As a result, server manufacturers will finally be able to market their energy-efficient products in the way they intended.

A last-minute change to the specs may cause blade servers to be excluded from Version 1.0 of the server ratings because the specification treats blade systems similarly to three- and four-socket systems, requiring power management solutions in lieu of idle power solutions. EPA’s position is that because blade systems are capable of competing directly with single- and dual-socket systems it is important that they be evaluated with the same metrics.

The Energy Star for Enterprise Servers spec covers servers with one to four processors and sets efficiency goals for servers at full load and also when idle. The standard will emphasize efficient power supplies and power management tools. To achieve an Energy Star rating, a server must be able to measure and report power usage, temperature, and processor utilization, and all of those features must be turned on when a server ships.

The May 15 release will be a Tier 1 standard, and will be followed by a more comprehensive Tier 2 standard that will combine computing performance and energy efficiency. The first draft of the Tier 2 standard should be released shortly after the Tier 1 spec is launched.


The EPA announced that it would begin the process of evaluating enterprise storage products for inclusion in the Energy Star program. Over the last year or so, EPA has facilitated discussions with product manufacturers, industry associations, and other interested parties to determine the benefits that IT users might realize from standardized information about the energy performance of storage equipment. Details on this process will be forthcoming in the next several weeks.

Pursuing Energy Star ratings for storage technologies is the next logical step in the Energy Star program for data centers. Other IT equipment such as routers and switches may find their way into the program soon thereafter.

The Storage Networking Industry Association (SNIA), the Storage Performance Council, and the Green Grid, among others, are working with the EPA on both server and storage specifications. SNIA operates a Green Storage Technical Working Group that is focused on developing Green Storage Metrics and measurements. Companies participating in the Green Storage TWG include Sun, IBM, 3PAR, Q-Logic, Seagate, LSI, Network Appliance, Pillar Data, EMC, HP, Brocade, and Copan, amongst others.

Pacific Gas & Electric is working with a technology company in Silicon Valley to establish a suitable method of determining energy efficiencies in storage devices in their data centers. Advanced encryption and encoding technologies now allow more data to be stored on less disk space, much like server virtualization allows more processing to be done on fewer servers. At this point, energy savings are calculated as the reduction in work realized by spinning fewer disks with the same storage capacity.

Other storage improvements, seen as possible next generation energy savers, include the “virtualization” of data storage as well as the utilization of flash memory where disk drives are currently used. These methods are bound to lead us to further efficiencies and miniaturization of data storage devices.

Stay Informed

To stay informed about the Energy Star specification development process for data centers, computer servers and storage devices, and any other EPA data center initiatives please visit:

Yahoo! recently hosted a meeting of the Critical Facilities Round Table (CFRT) where we witnessed EPA and LBNL personnel explain the nature of the government’s data center programs and request the collaboration of data center owners with government rule-makers. CFRT encourages its membership to support and participate in EPA and DOE initiatives in order to clearly voice the opinion of data center owners and operators in the rule-making process.