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ASHRAE Publishes First Zero Energy and Zero Carbon Building Evaluation Standard

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  • 27 Apr 2023
  • Standards
  • Atlanta, GA

ASHRAE Publishes First Zero Energy and Zero Carbon Building Evaluation Standard

Karen Buckley Washington
Senior Public Relations Specialist

ATLANTA (April 27, 2023) – ASHRAE has released a new standard to measure zero net carbon and energy goals in buildings.

ANSI/ASHRAE Standard 228-2023, Standard Method of Evaluating Zero Net Energy and Zero Net Carbon Building Performance, sets requirements for evaluating whether a building or group of buildings meets a definition of “zero net energy” or a definition of “zero net carbon” during building operation. The standard draws from ASHRAE Standard 105, among others, to address energy and carbon flows across a site boundary, their measurement, and their balance.

“Achieving a zero energy building has been viewed by many as a difficult goal to meet, with unforeseeable roadblocks and differing guidance,” said Keith Emerson, P.E., Life Member ASHRAE, chair of the Standards Project Committee 228. Standard 228 provides a consistent method for determining whether new and existing sites have reached zero energy. We hope this standard will become a helpful resource for building professionals in strategic decarbonization planning.”

Additional features of Standard 228 are as follows:

  • Allowances for sites that lack the opportunity to produce adequate renewable energy, while placing additional requirements on the use of external carbon and renewable energy in the calculation.
  • Defined calculation of energy in terms of source—a multiplier on the energy crossing the site boundary to include energy used or lost in extraction, generation and transit to the site.
  • The main energy calculation made in terms of annual average factors. Allowance is made for the calculation of individual hours where data is available.

Standard 228 does not apply to the establishment of building energy performance goals or limits; design guidance or design requirements; embodied energy of building materials and systems; and transportation to and from a building. The standard is also not intended to circumvent any safety, health, or environmental requirements.

To purchase Standard 228-2023, visit ashrae.org/228 or contact ASHRAE Customer Contact Center at 1-800-527-4723 (United States and Canada), 404-636-8400 (worldwide) or fax 678-539-2129.

Standard 228 has been published on continuous maintenance. A Standing Standard Project Committee (SSPC 228) has been formed to update the standard through the publication of addenda or revisions to any part of the standard. SSPC 228 is chaired by Dr. Paul Torcellini. Instructions for how to submit a change can be found on the ASHRAE website at ashrae.org/continuous-maintenance.


Founded in 1894, ASHRAE is a global professional society committed to serve humanity by advancing the arts and sciences of heating ventilation, air conditioning, refrigeration, and their allied fields.

As an industry leader in research, standards writing, publishing, certification and continuing education, ASHRAE and its members are dedicated to promoting a healthy and sustainable built environment for all, through strategic partnerships with organizations in the HVAC&R community and across related industries.

The Society is showcasing integrated building solutions and sustainability in action through the opening of the ASHRAE Global Headquarters building in metro-Atlanta, Georgia.

For more information and to stay up-to-date on ASHRAE, visit ashrae.org and connect on Instagram, LinkedIn, Facebook, Twitter and YouTube.