About Saving Energy in Data Centers

DOE's Advanced Manufacturing Office (AMO) is partnering with industry to reduce data center energy use and improve efficiency. Here you will find information about why data centers consume so much energy, the impact on electricity demand, and benefits and challenges. Some of the documents are available as Adobe Acrobat PDFs. Download Adobe Reader.

Photo of a man wearing a blue dress shirt typing on a laptop computer. Three metal computer network servers hang above the laptop.

Learn more about data center efficiency:

Leadership in Green IT, DOE Laboratories, Aug. 2011
Wireless Sensors Improve Data Center Energy Efficiency, Sept. 2010
U.S. Data Centers Save Energy Now (PowerPoint 3.4 MB), 2009
Opportunities for Combined Heat and Power in Data Centers Report, Mar. 2009
Data Center Assessments to Identify Efficiency Opportunities, Nov. 2008
Meeting Data Center Energy Challenges, Energy Matters Newsletter, Fall 2008
Quick Start Guide to Increase Data Center Energy Efficiency, Oct. 2008
Federal Energy Management Program Data Centers Initiative
Lawrence Berkeley National Laboratory Data Centers website

Data Center Energy Use

Data centers provide mission-critical computing functions essential to the daily operation of top U.S. economic, scientific, and technological organizations. These data centers consume large amounts of energy to run and maintain their computer systems, servers, and associated high-performance components.

To protect these systems and their vital functions, however, data centers also employ energy-intensive air conditioning systems, fire suppression systems, redundant/backup power supplies, redundant Internet connections, and high-security systems.

In 2006, U.S. data centers used approximately 61 billion kWh (about 209 trillion Btu in end use), accounting for about 1.5% of all U.S. electricity consumption.¹

Growing Electricity Demand

To support the growing demand for processing power throughout the economy, individual data centers increasingly use more compact and energy intensive servers even as the total number and size of data centers continues to increase. This growth in electricity demand by individual data centers and the rapidly increasing number of data centers nationwide represents a dramatic increase in electricity demand.

This figure is a rectangular graph with a vertical line just to the right of center dividing the graph in two parts. The left hand side is labeled "Historical energy use." The right hand side is labeled "Future energy use projections." The graph's vertical axis on the left is labeled "annual electricity use (billion kWh/year)", and is numbered from 0 to 120. The horizontal axis shows years, and is labeled 2000 to 2010. The line on the graph flows upwards from near the left hand bottom corner toward the upper right hand corner. It is a solid line when going through the "Historical energy use" section, then breaks into five lines when crossing over into the "Future energy use projections" section of the graph. At this point, one of the lines becomes a dashed line, which veers down toward the lower right side of the graph. This line is labeled "State of the art scenario." Another line is a darker dotted line which flows down and then straight across horizontally above the first line. This is labeled "Best practices scenario." The third line consists of longer dashes, and this line first heads down to the right corner, then shoots upward toward the right. This is labeled "Improved operation scenario." The fourth line heads toward the right hand upper corner until it reaches about three quarters of the way up the right side, and is labeled "Current efficiency trends scenario." The fifth and top line heads higher up toward the right hand upper corner and is labeled "Historical trends scenario." Underneath the figure are the words "Source: The Report to Congress on Server and Data Center Energy Efficiency, 2007."

Source: The Report to Congress on Server and Data Center Energy Efficiency, 2007

Data Center Efficiency Benefits and Challenges

Benefits of improving data center efficiency include:

Constrain increased electricity demand and associated carbon emissions
Protect data and computing functions vital to our economy
Reduce risk of power outages and increase regional electricity reliability
Postpone need to build new electricity generation capacity
Support replication of energy-efficient practices across the sector
Free up power and cooling.

Challenges to meeting data center energy reduction goals include:

Improving data center efficiency, reliability, and availability requires a team effort to address all system efficiency opportunities
Information technology (IT) equipment energy use is difficult to forecast
Energy-saving techniques must be updated continuously because computer technology evolves rapidly; new IT product requirements change faster than manufacturing processes
Tools for modeling energy management and heat transfer in data centers are complex and costly.

A coordinated program of focused R&D and operating practice improvements in data centers could produce large energy savings, reduce the load on the electric grid, and help protect the nation by increasing the reliability of critical computer operations.

Learn more about AMO's goals for saving energy in data centers, partnerships between government and industry to improve data center efficiency, and who to contact for more information.

Regulations and Guiding Principles

Executive Order 13514

Executive Order (E.O.) 13514 —Federal Leadership in Environmental, Energy, and Economic Performance —was signed on October 5, 2009. The order expanded on the energy reduction and environmental performance requirements of E.O. 13423, and mandated that federal agencies implement green data center strategies, double-sided printing, and PC power management as part of a broader sustainability push. Numerous energy requirements were set in several areas, including Electronic Products and Services, which requires agencies to implement best management practices for the energy efficiency management of servers and Federal data centers.

For more information on the order, visit the Federal Energy Management Program's E.O. 13514 Web page.

Standardizing Energy Efficiency Metrics

On January 13, 2010, DOE joined the Environmental Protection Agency and other industry leaders to form The Data Center Metrics Coordination Task Force. The purpose of the task force is to reach an agreement on data center energy efficiency measurements, metrics, and reporting conventions. As data center usage continues to escalate and energy costs rise, energy efficiency has become a growing concern for data center owners and operators. However, until recently, there was no standard approach for measuring energy usage, where to take the measurements, and how frequently to do the measuring. The organizations collaborating on this effort have developed agreed upon guiding principles for data center operators to gauge energy use and create opportunities for improved energy performance. In May 2011, the task force released a new report, Recommendations for Measuring and Reporting Overall Data Center Efficiency: Version 2 — Measuring PUE at Data Center, which completes the guidelines for applying the Power Usage Effectiveness (PUE) metric.

More information on the agreement and its guiding principles can be found in EERE's February 19, 2010, progress alert and AMO's February 1, 2010, press release. Further information can be found in Harmonizing Global Metrics for Data Center Energy Efficiency.

¹U.S. EPA, Report to Congress on Server and Data Center Energy Efficiency, Public Law 109-431, August 2007.