LEED, data center design standards
Building codes, industry standards, and regulations are used pervasively in the design and construction industry. Until recently, there were few documents on topics relating to energy-efficiency design strategies for data center facilities. Many that did exist were meant to be used for a limited audience, and others tended to be primarily anecdotal. All of that has changed over the past few years with the release of several peer-reviewed design guidelines from well-established organizations. I expect that in the near future there will be even more detailed standards and guidelines to draw from as the industry continues to evolve.
There are several primary organizations responsible for the development and maintenance of these documents: ASHRAE, U.S. Green Building Council, U.S. Environmental Protection Agency, U.S. Dept. of Energy, and The Green Grid, among others. This article presents an overview of some of the standards and guidelines from these organizations that provide specific advice on improving the energy efficiency in data center facilities.
USGBC: LEED adaptations for data centers
The new LEED data centers credit adaptation program was developed in direct response to challenges that arose when applying the current LEED standards to data center projects. These challenges are related to several factors, including the extremely high power density found in data centers. In response, the U.S. GBC has developed credit adaptations that address the primary challenges in certifying data center facilities. When the credit adaptations are released as a part of LEED 2012, they will apply to two LEED rating systems: Building Design and Construction, and Building Operations and Maintenance.
Because the two rating systems apply to buildings in different stages of their lifecycle, the credits are adapted in different ways. However, the adaptations were developed with the same goal in mind: establish LEED credits that are applicable to data centers specifically and that will provide tools for developers, owners, operators, designers, and builders to enable a reduction in energy use, minimize environmental impact, and provide a positive indoor environment for the inhabitants of the data center.
To that end, specific credits were targeted for modification:
Energy and Atmosphere—New Construction
- Prerequisite 1: Fundamental Commissioning of Building Energy Systems
- Prerequisite 2: Minimum Energy Performance
- Credit 1: Optimize Energy Performance
- Credit 3: Enhanced Commissioning
- Credit 5: Measurement and Verification.
Energy and Atmosphere—Existing Buildings
- Prerequisite 1: Energy Efficiency Best Management Practices—Planning, Documentation, and Opportunity Assessment
- Credit 2.1: Existing Building Commissioning—Investigation and Analysis
- Credit 3.1: Performance Measurement—Building Automation System.
A new credit also has been developed for cooling tower water management. This credit is critical to improve the water use efficiency in data centers that use water-cooled cooling plants. As of this writing, the credit adaptations have gone through one round of public comments. A second round will allow users to voice their opinions and make comments as to the viability of the credit adaptations.
Harmonizing global metrics
In its development of data center metrics such as Power Usage Effectiveness (PUE)/Data Center Infrastructure Efficiency (DCiE), Carbon Usage Effectiveness (CUE), and Water Usage Effectiveness (WUE), The Green Grid has sought to achieve a global acceptance to enable worldwide standardization of monitoring, measuring, and reporting data center energy use. This so-called global harmonization has manifested itself in the United States, European Union, and Japan reaching an agreement on guiding principles for data center energy-efficiency metrics. The specific organizations that participated in this effort were U.S. Dept. of Energy’s Save Energy Now and Federal Energy Management Programs; EPA’s Energy Star Program; European Commission Joint Research Center Data Centers Code of Conduct; Japan’s Ministry of Economy, Trade, and Industry; Japan’s Green IT Promotion Council; and the Green Grid.
As a starting point for further collaborative actions and joint research, the following basic tenets are listed in the document:
- Identify an initial set of metrics
- Define each metric
- Define the process for measurement of each metric
- Establish on-going dialog for development of additional metrics.
The document is written toward developing an ongoing dialog with the member organizations and establishes a path for future standards, metrics, and guidelines to be published. This dialog will be especially important when discussing performance-based energy metrics such as ones that measure IT performance per unit energy. These metrics will really help bring together the IT and facilities teams to optimize energy use in data centers.
In 2010, a task force consisting of representatives from leading data center organizations (7×24 Exchange, ASHRAE, The Green Grid, Silicon Valley Leadership Group, U.S. Dept. of Energy Save Energy Now Program, the EPA’s Energy Star Program, U.S. Green Building Council, and Uptime Institute) convened to discuss how to standardize the process of measuring and reporting PUE. They in turn appointed a task-force to develop detailed recommendations on how to measure and publish overall data center infrastructure energy efficiency. The objective was assigned with the understanding that many data centers operators may not currently have the capability to accurately measure all energy-consuming components within their facility and that there is currently much disparity in how these measurements are taken and what methods are used to analyze the data. One of the outcomes was the development of four categories of measurement, which align with The Green Grid’s measurement and reporting methodology. These categories represent techniques that range from relatively straightforward measurement and reporting methods to very detailed, multipoint measurement, analysis, and reporting of energy use, generating high levels of granularity in the data.
The purpose of the four levels is to encourage data center owners with limited measurement capability to participate in programs where power/energy measure is required while also outlining a process that allows operators to add additional measurement points to increase the accuracy of their measurement program. The goal is to recommend a consistent and repeatable measurement strategy that allows data center operators to monitor and improve the energy efficiency of their facility. A consistent measurement approach also will facilitate communication of PUE among data center owners and operators. It should be noted that caution must be exercised when an organization wishes to use PUE to compare different data centers, as it is necessary to first conduct appropriate data analyses to ensure that other factors such as levels of reliability and climate are not impacting the PUE.
Energy Star for data centers
In June 2010, the U.S. EPA released the data center model for its Portfolio Manager, an online tool for building owners to track and improve energy and water use in their buildings. This leveraged other building models that have been developed since the program started with the release of the office building model in 1999. The details of how data center facilities are ranked in the Portfolio Manager are discussed in a technical brief available on the EPA’s website.
Many of the steps required in attempting to obtain an Energy Star rating for a data center are fairly straightforward:
- Gross floor area
- IT energy configuration (designation of the location of the IT meter)
- IT energy meters
- Confirmation that the building meets the eligibility requirements
- Login to Portfolio Manager and enter the required energy and building information
- Determine if the building achieves a rating of 75 or above.
- Validate the Statement of Energy Performance (SEP) and Data Checklist by having a Licensed Professional Engineer or Registered Architect sign and stamp the SEP and sign the Data Checklist
- Read and understand the Energy Star Identity Guidelines
- Mail the signed Letter of Agreement and signed and stamped Statement of Energy Performance (SEP) along with the signed Data Checklist.
It is important to note that a licensed professional (architect or engineer) is required to validate the information that is contained in the Data Checklist. The role of the Licensed Professional is to verify:
- All energy use is accounted for accurately
- The building characteristics have been properly reported
- The building is fully functional in accordance with industry standards
- That each of the indoor environment criteria has been met.
The Licensed Professional should reference the 2010 Licensed Professional’s Guide to the Energy Star Label for Commercial Buildings for guidance in verifying a commercial building to qualify for the Energy Star designation.
With the addition of the data center model, the U.S. EPA now has 15 building models. Much of the work that went into developing the previous building models certainly benefited the new data center model; however, the reporting and ranking methodologies for data center buildings will continue to evolve after more owners submit their data to the EPA for evaluation. So in addition to possibly receiving an Energy Star certification, owners who submit their data are also assisting the industry as a whole in validating an important energy-efficiency reporting tool.
Green tips for data centers
The ASHRAE Datacom Series is a compendium of books that provides a foundation for developing an energy-efficient data center design. These books are under continuous maintenance by ASHRAE to incorporate the newest design concepts that are being introduced by the engineering community. The newest in the series, “Green Tips for Data Centers”, was conceived to be an engineering resource that overtly provides energy and water consumption reduction strategies. It is akin to the “ASHRAE Green Guide” in overall format and organization. However, it presents chapter-by-chapter technical guidance on energy and water-use mitigation approaches in the data center. The book is aimed at facility operators and owners, as well as engineers and other professional consultants.
The book was authored by industry professionals with the idea that by providing insight into practical techniques (that have proved successful at other datacom facilities), owners and operators will have confidence to implement similar techniques within their own facilities. The book is written to be holistic and highlights critical interdependencies of different technical domains. The primary chapters use a familiar organization:
- Energy Management
- Environmental Conditions
- Air Management
- Cooling Plant
- IT Power Distribution
- IT Equipment
While “Green Tips for Data Centers” is not a standard per se, it certainly is a formal document that establishes uniform engineering and technical criteria, methods, processes, and practices.
Other international programs and standards
Singapore Standard for Green Data Centers—Energy and Environmental Management Systems: It is important to point out that not all of the work in data center energy efficiency is happening within the United States. Dozens of other countries and municipalities worldwide are establishing sustainability metrics for technology-intensive facilities. One example of this is a recently announced program developed by Singapore’s Green Data Centre Standards Working Group.
As outlined in the group’s documentation, the standard is a certifiable, management system standard that provides data centers with a recognized framework as well as a logical and consistent methodology to achieve energy efficiency and continuous improvement. The standard also recommends best practices for data centers and lays out several metrics that can be used to measure performance and energy efficiency.
FIT4Green: An EU consortium made up of private and public organizations from Finland, Germany, Italy, Netherlands, Spain, and the UK, FIT4Green “aims at contributing to ICT energy reducing efforts by creating an energy-aware layer of plug-ins for data centre automation frameworks, to improve energy efficiency of existing IT solution deployment strategies so as to minimize overall power consumption, by moving computation and services around a federation of IT data centres sites.”
While many of the data center energy and sustainability programs take aim at the power and cooling systems, the focus of this effort is clearly directed toward “the beginning of the pipe”—the IT hardware itself. By developing a so-called “optimization layer,” the IT equipment will become power-aware and its operation will be optimized eliminating under-use and enabling very efficient processing.
Bill Kosik is principal data center energy technologist with HP Enterprise Business, Technology Services. Bill is one of the main technical contributors shaping HP Technologies Services’ energy and sustainability expertise. A member of the Consulting-Specifying Engineer editorial advisory board, he has written more than 20 articles and spoken at more than 30 industry conferences.