EN ISO 52120-1:2022

SLOVENSKI STANDARD
01-maj-2022
Nadomešča:
SIST EN 15232-1:2018
Energijske lastnosti stavb - Vpliv avtomatizacije, regulacije in upravljanja stavb - 1.
del: Splošni okvir in postopki (ISO 52120-1:2021, popravljena različica 2022-09)
Energy performance of buildings - Contribution of building automation, controls and
building management - Part 1: General framework and procedures (ISO 52120-1:2021,
Corrected version 2022-09)
Energieeffizienz von Gebäuden - Einfluss von Gebäudeautomation und
Gebäudemanagement - Teil 1: Allgemeiner Rahmen und Verfahren (ISO 52120-1:2021,
korrigierte Fassung 2022-09)
Performance énergétique des bâtiments - Contribution de l’automatisation, de la
régulation et de la gestion technique des bâtiments - Partie 1: Cadre général et
procédures (ISO 52120-1:2021, Version corrigée 2022-09)
Ta slovenski standard je istoveten z: EN ISO 52120-1:2022
ICS:
35.240.67 Uporabniške rešitve IT v IT applications in building
gradbeništvu and construction industry
91.120.10 Toplotna izolacija stavb Thermal insulation of
buildings
97.120 Avtomatske krmilne naprave Automatic controls for
za dom household use
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 52120-1
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2022
EUROPÄISCHE NORM
ICS 91.120.10 Supersedes EN 15232-1:2017
English Version
Energy performance of buildings - Contribution of building
automation, controls and building management - Part 1:
General framework and procedures (ISO 52120-1:2021,
Corrected version 2022-09)
Performance énergétique des bâtiments - Contribution Energieeffizienz von Gebäuden - Einfluss von
de l'automatisation, de la régulation et de la gestion Gebäudeautomation und Gebäudemanagement - Teil 1:
technique des bâtiments - Partie 1: Cadre général et Allgemeiner Rahmen und Verfahren (ISO 52120-
procédures (ISO 52120-1:2021, Version corrigée 2022- 1:2021, korrigierte Fassung 2022-09)
09)
This European Standard was approved by CEN on 3 December 2021.

This European Standard was corrected and reissued by the CEN-CENELEC Management Centre on 28 September 2022.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATIO N

EUROPÄISCHES KOMITEE FÜR NORMUN G

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 52120-1:2022 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
European foreword
This document (EN ISO 52120-1:2022) has been prepared by Technical Committee ISO/TC 205
"Building environment design" in collaboration with Technical Committee CEN/TC 247 “Building
Automation, Controls and Building Management” the secretariat of which is held by SNV.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by September 2022, and conflicting national standards
shall be withdrawn at the latest by September 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 15232-1:2017.
This document has been prepared under a Standardization Request given to CEN by the European
Commission and the European Free Trade Association.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 52120-1:2021, Corrected version 2022-09 has been approved by CEN as EN ISO 52120-
1:2022 without any modification.

INTERNATIONAL ISO
STANDARD 52120-1
First edition
2021-12
Corrected version
2022-09
Energy performance of buildings —
Contribution of building automation,
controls and building management —
Part 1:
General framework and procedures
Performance énergétique des bâtiments — Contribution de
l’automatisation, de la régulation et de la gestion technique des
bâtiments —
Partie 1: Cadre général et procédures
Reference number
ISO 52120-1:2021(E)
ISO 52120-1:2021(E)
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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ISO copyright office
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CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 52120-1:2021(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols, subscripts and abbreviated terms . 5
4.1 Symbols . 5
4.2 Subscripts . . 5
4.3 Abbreviated terms . 5
5 Description of the method . 6
5.1 Output of the method . . 6
5.2 General description of the method(s) . 6
5.3 Selection criteria between the methods . 6
5.4 BAC and TBM functions having an impact on the energy performance of buildings . 7
5.5 BAC efficiency class . 21
5.6 BAC and TBM functions assigned to the BAC efficiency classes .22
5.7 Applying BAC for EnMS and maintaining BAC energy efficiency . 32
5.7.1 General . 32
5.7.2 Applying BAC for EnMS . 32
5.7.3 Maintaining BAC energy efficiency . 32
6 Method 1 - Detailed calculation procedure of the BAC contribution to the energy
performance of buildings (detailed method) .33
6.1 Output data . 33
6.2 Calculation time intervals .34
6.3 Input data - Source of data .35
6.4 Calculation procedure . . 35
6.4.1 Applicable calculation time interval . 35
6.4.2 Energy performance calculation . 35
7 Method 2 - Factor based calculation procedure of the BAC impact on the energy
performance of buildings (BAC factor method) .38
7.1 Output data .38
7.2 Calculation time interval .38
7.3 Calculation procedure — Energy calculation .39
7.3.1 General .39
7.3.2 BAC efficiency factor values .40
7.3.3 Application of the BAC efficiency factors . 41
8 Simplified input data correlations . .42
9 Quality control .42
10 C ompl i a nc e c he c k .42
Annex A (informative) BAC efficiency factors .43
Annex B (normative) Minimum BAC function type requirements .48
Annex C (informative) Determination of the BAC efficiency factors .52
Annex D (informative) Examples of how to use the BAC function list of ISO 16484-3 to
describe functions from this document .70
Annex E (informative) Applying BAC for EnMS specified in ISO 50001:2018 .73
Annex F (informative) Maintain BAC energy efficiency .87
Annex G (informative) Control accuracy .90
iii
ISO 52120-1:2021(E)
Bibliography .91
iv
ISO 52120-1:2021(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 205, Building environment design, in
collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/
TC 247, Building Automation, Controls and Building Management, in accordance with the Agreement on
technical cooperation between ISO and CEN (Vienna Agreement).
A list of all parts in the ISO 52120 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
This corrected version of ISO 52120-1:2021 incorporates the following corrections:
— Figure C.12 has been replaced.
v
ISO 52120-1:2021(E)
Introduction
This document belongs to the family of standards aimed at international harmonization of the
methodology for the assessment of the energy performance of buildings. Throughout, this group of
standards is referred to as a set of called “EPB set of standards”.
All EPB standards follow specific rules to ensure overall consistency, unambiguity and transparency.
This document is clearly identified in the modular structure developed to ensure a transparent and
coherent set of EPB standards, as set out in ISO 52000-1, the overarching EPB standard. BAC (building
automation and control) is identified in the modular structure as technical building system M10.
However, other International Standards issued by ISO TC 205 deal with control accuracy, control
functions and control strategies using standards communications protocol (these last standards do not
belong to the set of EPB standards).
To avoid a duplication of calculation due to the BAC (avoid double impact), no calculation is done in a
BAC EPB standard set, but in each underlying standard of the set of EPB standards (from M1 to M9 in
the modular structure), an identifier developed and present in the M10 covered by this document is
used where appropriate. This way of interaction is described in detail in ISO/TR 52000-2, the Technical
Report accompanying ISO 52000-1. As consequence, the concept of a normative template for specific
(national) choices in Annex A, and Annex B with informative default choices, as commonly used in the
set of EPB standards is not applicable for this document.
The main target groups of this document are all the users of the set of EPB set of standards (e.g.
architects, engineers, regulators).
Further target groups are parties wanting to motivate their assumptions by classifying the building
energy performance for a dedicated building stock.
[5]
More information is provided in the Technical Report accompanying this document (ISO/TR 52120-2 ).
NOTE 1 Table 1 shows the relative position of this document within the set of EPB standards in the context of
the modular structure as set out in ISO 52000-1.
NOTE 2 In ISO/TR 52000-2 the same table can be found, with, for each module, the numbers of the relevant
EPB standards and accompanying technical reports that are published or in preparation.
NOTE 3 The modules represent EPB standards, although one EPB standard can cover more than one module
and one module can be covered by more than one EPB standard, for instance a simplified and a detailed method
respectively. See also Clause 2 and Tables A.1 and B.1.
Table 1 — Position of this document (in casu M10–4,5,6,7,8,9,10), within the modular structure
of the set of EPB standards
Over-arching Building Technical building system
(as such)
sub1 M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M11
1 General General General
a
The shaded modules are not applicable.
vi
Submodule
Descriptions
Descriptions
Descriptions
Heating
Cooling
Ventilation
Humidification
Dehumidification
Domestic hot
waters
Lighting
Building automa-
tion and control
PV, wind, etc.
ISO 52120-1:2021(E)
TTabablele 1 1 ((ccoonnttiinnueuedd))
Over-arching Building Technical building system
(as such)
sub1 M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M11
Common
terms and
definitions; Building ener-
2 Needs
symbols, gy needs
units and
subscripts
(Free) indoor
Maximum
conditions
3 Application load and
without sys-
power
tems
Ways to ex- Ways to ex- Ways to ex-
4 press energy press energy press energy    x
performance performance performance
Building
Heat transfer
functions Emission and
5 by transmis-    x
and building control
sion
boundaries
Building Heat transfer
occupancy by infiltration Distribution
6    x
and operating and ventila- and control
conditions tion
Aggregation
of energy
Internal heat Storage and
7 services and    x
gains control
energy car-
riers
Building par- Solar heat Generation
8    x
titioning gains and control
Load dis-
Calculated Building dy-
patching and
9 energy per- namics (ther-    x
operating
formance mal mass)
conditions
Measured Measured Measured
10 energy per- energy perfor- energy per-    x
formance mance formance
11 Inspection Inspection Inspection
Ways to ex-
12 press indoor BMS
comfort
External
13 environment
conditions
Economic
a
calculation
a
The shaded modules are not applicable.
vii
Submodule
Descriptions
Descriptions
Descriptions
Heating
Cooling
Ventilation
Humidification
Dehumidification
Domestic hot
waters
Lighting
Building automa-
tion and control
PV, wind, etc.
INTERNATIONAL STANDARD ISO 52120-1:2021(E)
Energy performance of buildings — Contribution of
building automation, controls and building management —
Part 1:
General framework and procedures
1 Scope
This document specifies:
— a structured list of control, building automation and technical building management functions which
contribute to the energy performance of buildings; functions have been categorized and structured
according to building disciplines and building automation and control (BAC);
— a method to define minimum requirements or any specification regarding the control, building
automation and technical building management functions contributing to energy efficiency of a
building to be implemented in building of different complexities;
— a factor-based method to get a first estimation of the effect of these functions on typical buildings
types and use profiles;
— detailed methods to assess the effect of these functions on a given building.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 50001:2018, Energy management systems — Requirements with guidance for use
ISO 52000-1:2017, Energy performance of buildings — Overarching EPB assessment — Part 1: General
framework and procedures
ISO 7345:2018, Thermal performance of buildings and building components — Physical quantities and
definitions
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 7345:2018, ISO 52000-1:2017
and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
ISO 52120-1:2021(E)
3.1
auxiliary energy
electrical energy used by technical building systems (3.14) to support energy transformation to satisfy
energy needs
Note 1 to entry: This includes energy for fans, pumps, electronics, etc. Electrical energy input to the ventilation
system for air transport and heat recovery is not considered as auxiliary energy, but as energy used for
ventilation.
Note 2 to entry: In ISO 9488 the energy used for pumps and valves is called “parasitic energy”.
[SOURCE: ISO 13612-2:2014, 3.3, modified — Note 3 to entry was removed.]
3.2
building automation and control
BAC
products, software, and engineering services for automatic controls, monitoring and optimization,
human intervention and management to achieve energy-efficient, economical, and safe operation of
building services equipment
[SOURCE: ISO 52000-1:2017, 3.4.4, modified — The term BAC was added.]
3.3
building automation and control system
BACS
system, comprising all products, software and engineering services for automatic controls (including
interlocks), monitoring, optimization, for operation, human intervention, and management to achieve
energy-efficient, economical, and safe operation of building services
Note 1 to entry: BACS is also referred to as BMS (building management system).
Note 2 to entry: The use of the word ‘control’ does not imply that the system or device is restricted to control
functions (3.5). Processing of data and information is possible.
Note 3 to entry: If a building control system, building management (3.4) system, or building energy management
system complies with the requirements of the ISO 16484 series, it should be designated as a building automation
and control system (BACS).
Note 4 to entry: Building services are divided in technical, infrastructural and financial building services and
energy management is part of technical building management (3.13).
Note 5 to entry: Building energy management system is part of a BMS.
Note 6 to entry: The building energy management system comprises data collection, logging, alarming,
reporting, and analysis of energy usage, etc. The system is designed to reduce the energy consumption, improve
the utilization, increase the reliability, and predict the performance of the technical building systems (3.14), as
well as optimize energy usage and reducing its cost.
[SOURCE: ISO 16484-2:2004, 3.31, modified — Notes to entry 1, 4, 5 and 6 have been added.]
3.4
building management
BM
totality of services involved in the management operation and monitoring of buildings (including plants
and installations)
Note 1 to entry: Building management can be assigned as part of facility management.
[SOURCE: CEN/TS 15379:2009, 3.4, modified – Second part of the definition became Note 1 to entry.]
ISO 52120-1:2021(E)
3.5
control function
BAC (3.2) effect of programs and parameters
Note 1 to entry: BAC functions are referred to as control functions, I/O, processing, optimization, management
and operator functions. They are listed in the BAC FL (function list) for a specification of work.
Note 2 to entry: Function is a program unit that delivers exactly one data element, which can be a multiple value
(i.e. an array or a structure). Functions can be an operand in a program as described in EN 61131–3.
3.6
delivered energy
energy, expressed per energy carrier (3.7), supplied to the technical building systems (3.14) through the
assessment boundary, to satisfy the uses taken into account or to produce the exported energy
Note 1 to entry: Delivered energy can be calculated for defined energy uses or it can be measured.
[SOURCE: ISO 52000-1:2017, 3.4.6]
3.7
energy carrier
substance or phenomenon that can be used to produce mechanical work or heat or to operate chemical
or physical processes
[SOURCE: ISO 52000-1:2017, 3.4.9]
3.8
energy need for heating and cooling
heat to be delivered to or extracted from a thermally conditioned space to maintain the intended space
temperature conditions during a given period of time
Note 1 to entry: The energy need can include additional heat transfer resulting from non-uniform temperature
distribution and non-ideal temperature control, if they are taken into account by increasing (decreasing) the
effective temperature for heating (cooling) and not included in the heat transfer due to the heating (cooling)
system.
[SOURCE: ISO 52000-1:2017, 3.4.13, modified — Note 1 to entry added and the term was originally
"energy need for heating or cooling".]
3.9
energy efficiency
ratio or other quantitative relationship between an output of performance, service, goods or energy,
and an input of energy
EXAMPLE Efficiency conversion; energy required/energy used; output/input; theoretical energy used to
operate/energy used to operate.
Note 1 to entry: Both input and output need to be clearly specified in quantity and quality, and be measurable.
[SOURCE: ISO 50001:2018, 3.5.3, modified — "commodities" was removed from the definition and the
example has been modified.]
3.10
integrated function
BAC (3.2) effect of programs, shared data points and parameters for multi-discipline interrelationships
between various building services and technologies
ISO 52120-1:2021(E)
3.11
measured energy performance
energy performance based on measured amounts of delivered and exported energy
Note 1 to entry: The measured rating is the weighted sum of all energy carriers (3.7) used by the building, as
measured by meters or derived from measured energy by other means. It is a measure of the in-use performance
of the building after correction or extrapolation. This is particularly relevant to certification of actual energy
performance.
Note 2 to entry: Also known as “operational rating”.
[SOURCE: ISO 52000-1:2017, 3.5.16, modified — "weighted measured amounts" has been replaced by
"measured amounts" in the definition and "energy performance" has been replaced by "rating".]
3.12
thermally activated building system
TABS
massive building fabric actively heated or cooled by integrated air- or water-based systems
3.13
technical building management
TBM
process(es) and services related to operation and management of buildings and technical building system
(3.14) through the interrelationships between the different disciplines and trades
Note 1 to entry: The disciplines and trades comprise all technical building services for the purpose of optimized
maintenance and energy consumption.
EXAMPLE Optimization of buildings through interrelationships ranging from heating, ventilation and air
conditioning (HVAC), to lighting and day lighting, to life safety and security, to electric power systems and energy
monitoring and metering, to services, including communications and maintenance and to management.
[SOURCE: ISO 52127-1:2021, 3.2]
3.14
technical building system
technical equipment for heating, cooling, ventilation, humidification, dehumidification, domestic hot
water, lighting and electricity production
Note 1 to entry: A technical building system can refer to one or to several building services (e.g. heating, heating
and DHW).
Note 2 to entry: A technical building system is composed of different subsystems.
Note 3 to entry: Electricity production can include cogeneration and photovoltaic systems.
[SOURCE: ISO 52000-1:2017, 3.3.13, modified — The phrase "building automation and control" was
deleted from the definition.]
3.15
EPB standard
standard that complies with the requirements given in ISO 52000-1, CEN/TS 16628 and CEN/TS 16629
Note 1 to entry: These three basic EPB documents were developed under a mandate given to CEN by the European
Commission and the European Free Trade Association (Mandate M/480), and support essential requirements of
EU Directive 2010/31/EC on the energy performance of buildings (EPBD). Several EPB standards and related
[5] [6]
documents are developed or revised under the same mandate. CEN/TS 16628 and CEN/TS 16629 are
available as N-documents in ISO/TC 163 and ISO/TC 205.
[SOURCE: ISO 52000-1:2017, 3.5.14, modified — The last sentence of the Note 1 to entry has been added.]
ISO 52120-1:2021(E)
4 Symbols, subscripts and abbreviated terms
4.1 Symbols
For the purposes of this document, the symbols given in ISO 52000-1 and Table 2 apply.
Table 2 — Symbols
Symbol Quantity Unit
a normalized level, e.g. occupancy or gains -
mean part load -
β
Φ heat flow rate, thermal power kW
4.2 Subscripts
For the purposes of this document, the subscript given in ISO 52000-1:2017, Clause 4 and Annex C and
the specific subscripts listed in Table 3 apply.
NOTE Relevant subscripts already given in ISO 52000-1 are included if necessary for the understanding of
this document.
Table 3 — Subscripts
Subscript Term Subscript Term Subscript Term
amb ambient end end th thermal
BAC building automation r room trans transfer
and control
cor correction ref reference
ctr control set setpoint
DHW domestic hot water sta start
4.3 Abbreviated terms
For the purposes of this document, the abbreviated terms given in ISO 52000-1 and Table 4 apply.
Table 4 — Abbreviated terms
AHU air handling unit
BAC building automation and control
BM building management
COP coefficient of performance
DHW domestic hot water
HVAC heating, ventilation and air conditioning
TABS thermally activated building systems
TBM technical building management
VFD variable flow dependant
VRF variable room flow
ISO 52120-1:2021(E)
5 Description of the method
5.1 Output of the method
This document describes two methods of how to calculate the contribution of building automation and
controls to the energy performance of buildings. The two methods are the following.
— The detailed method: output of the detailed method is a list of automation, control and management
function types that is used to run a detailed calculation of building energy performance based on
other EPB standards. In addition, the detailed method would also allow classification of a building
automation and control system according to a set of criteria defined in this document. There is no
limitation regarding the time interval.
— The factor-based method: output of the factor-based method is the energy demand of a building
according to a given building automation and control classification. The time interval of the output
is a yearly step.
5.2 General description of the method(s)
Two methods are given:
— method 1, defined in Clause 6, is meant for a detailed energy performance analysis of a building
in case detailed information about the building, the HVAC systems and especially the type of
automation, control and management functions are available that can be applied in a holistic EPB
calculation method;
— method 2, defined in Clause 7, is intended for easily calculating a rough estimate of the impact of
building automation, control and management on the energy performance of a building based on a
given energy performance (either a consumption metered, or a demand calculated) correlated to a
certain BAC efficiency classification of the building.
In this document, “factor-based method” is exemplified by “BAC factor method”.
5.3 Selection criteria between the methods
For the calculation of the impact of building automation, control and management functions on the
building energy performance the detailed method is method 1 in this document. Figure 1 illustrates
how to use the detailed method compared to the simplified BAC factor method.
ISO 52120-1:2021(E)
a
Delivered energy is the total energy, expressed per energy carrier (gas, oil, electricity etc.) used for heating,
cooling, ventilation, domestic hot water or lighting.
NOTE Arrows illustrate only the calculation process and do not represent energy and/or mass flows.
Figure 1 — Detailed method in comparison with BAC factor method
The detailed method should be used only when a sufficient knowledge about automation, control and
management functions used for the building and the energy systems is available. The application of
the detailed calculation procedure implies that all automation, control and management functions that
have to be accounted for the operation of a building and its energy systems are known. Clause 6 gives a
general survey of those functions and describes how to use them in the context of energy performance
calculations.
5.4 BAC and TBM functions having an impact on the energy performance of buildings
Building automation and control (BAC) provide effective control functions for any building energy
system, for example, heating, ventilating, cooling, hot water and lighting appliances, that lead to improve
operational and energy efficiencies. Complex and integrated energy saving functions and routines can
be configured based on the actual use of a building, depending on real user needs, to avoid unnecessary
energy use and CO emissions.
Technical building management (TBM) functions as part of building management (BM) and provides
information about operation, maintenance, services and management of buildings, especially for
energy management, e.g. measurement, recording trending, and alarming capabilities and diagnosis of
unnecessary energy use. Energy management provides requirements for documentation, controlling,
monitoring, optimization, determination and to support corrective action and preventive action to
improve the energy performance of buildings. This document can be used to evaluate the contribution
of these building management functions to the energy performance of buildings.
The BAC functions described in Table 5 are based on the energy demand and supply model for a building
in Figure 2.
ISO 52120-1:2021(E)
Figure 2 — Energy demand and supply model (example: heating plant)
Rooms represent the source of the energy demand. Suitable equipment should ensure comfortable
conditions in the rooms with regard to temperature, humidity, air quality and light as needed. Local
regulations can specify minimum or maximum requirements.
Supply media is provided to the consumer according to energy demand keeping losses in distribution
and generation to an absolute minimum.
The building automation and control functions described in Table 5 are aligned in accordance with the
energy demand and supply model. The relevant energy-efficiency functions are handled starting with
the room, via distribution up through generation.
The most common BAC and TBM functions having an impact on the energy performance of buildings
have been described and summarized in Table 5.
Figures 3 to 7 illustrate basic system designs for heating, domestic hot water, cooling, ventilation and
air conditioning purposes. The numbers refer to the control functions summarized in Table 5. These
basic elements can be combined to more or less complex systems that also account for local, regional
or national specifics. The building automation and control functions defined in Table 5 are according
to these basic system designs. Air side system control of HVAC shall be treated as ventilation and air-
conditioning control, separately from heat generators, chillers, terminal units and water and refrigerant
side controls.
Annex D provides examples of how to use the BAC function list of ISO 16484-3 to describe functions
from this document. In addition, Annex G gives informative control accuracy requirements.
ISO 52120-1:2021(E)
Key
1 heat generator
2 thermal energy storage
3 air handling unit
4 room
5 heating water supply
6 heating water return
a
These numbers refer to the numbers in Table 5.
Figure 3 — Space heating system
Key
1 solar collector
2 boiler/district heating heat pump
3 domestic hot water storage
4 heating water supply
5 heating water return
a
These numbers refer to the numbers in Table 5.
Figure 4 — Domestic hot water heating system
ISO 52120-1:2021(E)
Key
1 chiller
2 thermal energy storage
3 air handling unit
4 room
5 chilled water supply
6 chilled water return
a
These numbers refer to the numbers in Table 5.
Figure 5 — Cooling system
Key
1 outdoor unit
2 indoor unit
3 room
4 controller
a
These numbers refer to the numbers in Table 5.
Figure 6 — Split system/VRF (heating and/or cooling)
ISO 52120-1:2021(E)
Key
1 exhaust air
2 outside air
3 room
4 variable air volume
5 chilled water supply
6 chilled water return
7 heating water supply
8 heating water return
a
These numbers refer to the numbers in Table 5.
Figure 7 — Ventilation and air-conditioning system
Table 5 — BAC and TBM functions having an impact on the energy performance of buildings
Automatic control
1 Heating control
1.1 Emission control HEAT_EMIS_CTRL_DEF M3–5
The control function is applied to the heat emitter (radiators, underfloor heating, fan-
coil unit, indoor unit) at room level; for type 1, one function can control several rooms.
0 No automatic control of the room temperature
1 Central automatic control: there is only central automatic control acting either on the
distribution or on the generation. Function is to be integrated in a system.
2 Individual room control: by thermostatic valves or electronic controller
3 Individual modulating room control with communication: between controllers and
BACS (e.g. scheduler, room temperature setpoint)
4 Individual modulating room control with communication and occupancy detection:
between controllers and BACS; demand control/occupancy detection (this function
level is usually not applied to any slow reacting heat emission systems with relevant
thermal mass, e.g. floor heating, wall heating)
1.2 Emission control for TABS (heat- HEAT_EMIS_CTRL_TABS M3–5
ing mode)
0 No automatic control of the room temperature
1 Central automatic control: the central automatic control for a TABS zone (which com-
prises all rooms which get the same supply water temperature
...