ATLANTA — ASHRAE released a revised version of its energy standard for data centers.

ANSI/ASHRAE Standard 90.4-2019, Energy Standard for Data Centers, establishes the minimum energy-efficiency requirements for the design and operation of data centers, with special consideration to their unique load requirements compared to other buildings. Standard 90.4 applies to data centers with a conditioned floor area greater than 20 W per square foot and IT equipment loads greater than 10 kW. It contains specific requirements for mechanical and electrical systems installed in new data centers or in data center additions/alterations that require new mechanical or electrical systems.

“Standard 90.4 was developed under the guiding principle that data centers are mission critical facilities that demand careful attention to the potential impact of requirements,” said Richard Zbin, chair of the Standard 90.4 committee. “The updated standard enables operators and designers to use the latest and most effective equipment and techniques to achieve energy efficiency in data centers while avoiding potential reliability issues.”

The following list is a summary of the updates.

  • Renumbered sections and revised wording align more closely with that of Standard 90.1.
  • Mechanical efficiency requirements are based entirely on yearly energy calculations and no longer include a power calculation option. Included table values are also aligned with the newest ASHRAE Climate Zones.
  • Significant improvements are made to uninterruptible power supply (UPS) technology. Mechanical and electrical infrastructure elements are addressed. Updated UPS segment tables reflect available hardware, and average outputs are also included.

Standard 90.4 has been in a continuous state of development as a code-intended companion to Standard 90.1 since 2013. The standard requires compliance with Standard 90.1 for building envelope, service water heating, lighting, and other equipment.

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