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ANSI/ASHRAE Standard 228, Standard Method of Evaluating Zero Net Energy and Zero Net Carbon Building Performance

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ASHRAE Publishes First Zero Net Energy and Zero Net Carbon Standard

ASHRAE Standard 228 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. 

  • Standard 228 draws from ASHRAE Standard 105, among others, to address energy and carbon flows across a site boundary, their measurement, and their balance.
  • It includes allowances for sites that lack opportunity to produce adequate renewable energy, while placing additional requirements on the use of external carbon and renewable energy in the calculation.
  • The standard defines the 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 is made in terms of annual average factors, but allowance is made for the calculation of individual hours where data available.

Purchase Standard 228-2023