ANSI/ASHRAEStandard90.4-2022
(Supersedes ANSI/ASHRAE Standard 90.4-2019)Includes ANSI/ASHRAE addenda listed in Appendix E
Energy Standard for Data Centers
See Informative Appendix E for approval dates by ASHRAE and the American National Standards Institute.
This Standard is under continuous maintenance by a Standing Standard Project Committee (SSPC) for which the Standards Commiteeasstablihedumnepgramreguapuliatinfddendrevisnsningroeder timely documented consensus action onrequestsfor change to any part of the Standard.Instructions forhow to submit achange can be found on the ASHRAE website (
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Online supporting files include Section 6 MLC calculation examples.
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Cognizant TC: 9.9 Mission Critical Failities Data Centers Technology Spaces and Electronic Equipment ASHRAE Standard Project Committee 90.4 SPLS Liaison: Jennifer A. Isenbeck ASHRAE Staff Liaison: Thomas Loxley
Susanna S. Hanson ChoirWilliam P. Bahnfleth Jonathan Humble Vice-ChoirThomas E. CappelinDouglas D. Fick Patricia GraefJaap HogelingPhillip A.J ohson Jennifer A IsenbeckSrinivas Katipamula
SPECIAL NOTE
by the American National Standards Institute (ANSI) of which ASHRAE is a member and which has approved this Standard as an ANS as This American National Standard (ANS) is a national voluntary consensus Standard developed under the auspices of ASHRAE. Consersus i defined"subtantial greementreached by dreclyandmaterialyaffected interest categories. Thisignifes theconcurrence ofmorethanasimle majority. but not ecesarly unnimityCnsensusrequires thtal views andbectioseconsidered andthat aneffort emadetwd theireslutin.Compliance with thisStandard is voluntary untiland unless a legal jurisdiction makes plance mandatory through lgislation.
ASHRAE obtains consensus through participation of its national and itemational members assciated societies and publi revew.
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CONTENTS
ANSI/ASHRAEStandard90.4-2022 Energy Standard for Data Centers
SECTION
Foreword 21 Purpose.. .22 Scope.... ..33 Definitions .35 Building Envelope 4 Administration and Enforcement. ..76 Heating. Ventilating. and Air Conditioning. ...9 ..97 Service Water Heating ... 138 Power.... ..139 Lighting. 1710 Other Equipment ..... .1712 Normative References. 11 Alternative Compliance Method ...1.7 20Informative Appendix A: Informative References.. 21Informative Appendix B: Sample Submittal Forms.. .26Informative Appendix C: Tools for lllustrating Compliance.. 32Informative Appendix D: Additional Guidance on Telephone Exchanges .50Informative Appendix E: Addenda Description Information... .51Annex 1: Reference Standard Reproduction Annex-ASHRAE/IES Standard 90.1-2022. .52> Standard 90.4 MLC HVAC Calculation Examples:
NOTE
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FOREWORD
ANSI/ASHRAE Standard 90.4 was initiated to promote energy-effcient design of data centers α rapidlyexpanding and energy-intensive category among buildings in the United States and worldwide. Since 2013.Standard 90.4 has been in α continuous state of development as α code-intended panion to ASHRAE/IES Standard 90.1.Stanard 90.4 stillrequires lincewith Standard 90.1for thebilding emelope sevicmuch more specialized cooling and electrical systems in data centers and requires designers to satisfy the water heating lighting and othercoventionalbilding aspects.HoweverStandard 90.4alsoaddresses thappropriate pliance paths corresponding to their data center projects as delineated inSection 4. Com-pliance is based on meeting or exceeding wo minimum efficiency vales as defined in Sections 6 and 8: the mechanical load ponent (MLC) and the electrical loss ponent (ELC)For optimal utility maximmvaluesfoMLCvaryby indicated climatezone.Howeverdatacenter putingequjpmenelectricallads arenot αfonction ofweather conditions so are notclimate zonedependent.In the event that the design ndparticularly the electrical ormechanicalequipment nvolved in upgrades orrenovationscannot meet theMLC or ELC requirements in the standard Section II allows trade-offs berween the fwo ponents.
Informative Appendix E contains α summary of addendo to the 2019 edition of Standard 90.4 that hcvebeen incorporated into the 2022 edition. Key changes include the following:
α.Section 6.5 adds additional options for mechanical load ponent calculations.
which are listed at only 35% loadingan unrealistic level for most data centers.credit to the bined MLC and ELC for the deployment of onsite renewable energy; thereby incentiviz-ing the consideration of renewable energy while still requiring energy-efficient mechanical and electri- cal systems.
d. Language has been incorporated to give credit for and to encourage heat recovery. However the method of credit calculation is very specific to avoid double dipping.
Standard90.fllwsASHAEsonsten proesihllhgettstardto be made on contirmous basis through adendo o the existing standard. This process allows for frequentthe chirs of the mittees responsible for both Standard 90.1 and Standard 90.4 meet with members of theASHRAE Standards Committee to address any conflicts in scope beween the wo stndards. It is the hope of the mitee that knowledgeable people wirhin the data center industry will continue to ofer their talentsto sustain and improve the quality and accuracy of the standard moving forwand.
1.PURPOSE
The purpose of this standard is to establish the minimum energy efficiency requirements of data centers for
a. design construction and a plan for operation and maintenance; andb. use of on-site or off-site renewable energy resources.
2. SCOPE
2.1 This standard applies to
a. new data centers or portions thereof and their systems;b. new odditions to data centers or portions thereof and their systems; and C. modifications to systems and equipment in existing data centers or portions thereof.
2.2 The provisions of this standard do not apply to
a.telephone exchanges b. essential facifities andC.information technology equipment (ITE).
2.3 Where specifically noted in this standard certain other buildings or elements of buildings shall beexempt.
3.DEFINITIONS
3.1 General. Certain terms abbreviations and acronyms are defined in this section for the purposes of this standard. When the tense or plurality of the term differs from the defined term the defined term still applies.These definitions are applicable to all sections of this standard except where specifically limited.
Standard 90.1 those terms shall have the meanings as assigned to them in ANSI/ASHRAE/IES Standard 3.1.1 Coordination. Where terms are not defined in this standard but are defined in ANSI/ASHRAE/IES90.1. Where terms are not defined in either document they shall have their ordinary accepted meaningscan English language usage as documented in an unabridged dictionary accepted by the adopring authority. within the context in which they are used. Ordinarily accepted meanings shall be based on standard Ameri-
Informative Notes:
2. Only terms that appear in Section 3 of this standard are italicized throughout the document. 1. See Annex 1 for ANSI/ASHRAE/IES Standard 90.1 definitions.
3.2 Definitions
addition: see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
adoprting authority: see ANSI/ASHRAE/TES Standard 90.1 in Annex 1.
air ambient: the air surrounding a building or space; the source of outdoor air brought into a building.
air recirculated: air removed from a space and reused as supply air.
air supply: air delivered by mechanical or natural ventilation to a space posed of any bination ofoutdoor air recircufated air or transfer ait.
alterarion: see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
dnd o e o s p p prejection annual energy use divided by the data center ITE energy.
authority heving jurisdiction (AHJ): see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
antomatic or aufomatically: see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
branch circuit: see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
building: see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
building envelope: see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
bwilding official: see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
cabinet: a container that encloses connection devices terminations apparatus wiring and equipmenf.
circuit breaker: see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
puter room: arom or portions of a bilding serving anEload less than or equal to10 kW or 20 W/f²(215 W/m²) or less of conditioned floor area.
conditiomed floor area: see conditioned floor area gross in ANSI/ASHRAE/IES Standard 90.1 in Annex 1
consfruction: see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
construction documents: see ANSI/ASHRAE/IES Standard 90.1 in Annex 1.
data center aroom or bilding or portions thereof including pter rooms being servedby the data center systems serving a total /TE load greater than 10 kW' and 20 W/f² (215 W/m²) of conditioned foor arec.
