ISO 12655:2013

INTERNATIONAL ISO
STANDARD 12655
First edition
2013-03-01
Energy performance of buildings —
Presentation of measured energy use
of buildings
Performance énergétique des bâtiments — Présentation de
l’utilisation énergétique réelle des bâtiments
Reference number
©
ISO 2013
© ISO 2013
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ii © ISO 2013 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Building energy use defined by usage . 2
4.1 Classification of building energy use by usage . 2
4.2 Energy for space heating . 2
4.3 Energy for space cooling. 2
4.4 Energy for air movement . 2
4.5 Energy for domestic hot water . 3
4.6 Energy for lighting . 3
4.7 Energy for household/office appliances . 3
4.8 Energy for indoor transportation . 3
4.9 Energy for building auxiliary devices . 3
4.10 Energy for cooking . 3
4.11 Energy for cooling storage . 3
4.12 Energy for devices in data center. 3
4.13 Energy for other specific functional devices . 3
5 Building energy use defined by boundary . 4
5.1 Identification of building energy use by boundary . 4
5.2 Heat/cold reaching the building space (E ) . 4
B
5.3 Energy delivered to the building’s technical system (E ) . 4
T
5.4 Energy input to the district heating/cooling system (E ) . 5
D
5.5 Renewable energy produced on the building site (E ) . 5
R
5.6 Terms and symbols of the categories of building energy use determined by boundary . 5
6 Expression of energy carriers . 7
6.1 Expression methods of energy carriers. 7
6.2 Presenting building energy use data with original energy carriers . 7
6.3 Presenting building energy use data with equivalent energy . 7
7 Presentation of building energy use . 7
Annex A (normative) Symbols and abbreviations . 8
Annex B (informative) Presentations of building energy use: examples.10
Bibliography .14
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International
Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies
casting a vote.
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.
ISO 12655 was prepared by Technical Committee ISO/TC 163, Thermal performance and energy use in
the built environment.
iv © ISO 2013 – All rights reserved

Introduction
This International Standard is prepared by ISO/TC 163,/WG 4, a joint group between ISO/TC 163, Thermal
performance and energy use in the built environment and ISO/TC 205, Building environment design.
It provides a set of clear definitions, terms and procedures for presenting the energy use in buildings in
a consistent and uniform way, including:
— Classifications of building energy use by purpose (e.g. energy for space heating, energy for cooking,
energy for lighting);
— Categories of energy use by boundaries inside or outside of buildings (e.g. actual heat/cold reaching
the building space (E ), energy delivered to the building’s technical system (E ), energy used by the
B T
district heating/cooling system (E );
D
— Building energy data shall be presented with original energy carriers or with equivalent energy,
and the indication (subscript) is required to make the data understandable.
Such a comprehensive expression of building energy use is of great importance for an in-depth
understanding of building energy performances and trends. And it is conducive to:
a) Regulating the presentation of the energy use of buildings with respect to data collection, metering
and analysis;
b) Providing a uniform platform for the assessment and comparison of building energy;
c) Laying the foundation of energy data collection, metering, statistics, audit and analysis for both
regional and national buildings.
The measuring methods are out of scope of this International Standard.
Relationship with ISO/TR 16344, ISO 16343 and ISO 16346
Three relevant International Standards, ISO/TR 16344, ISO 16343 and ISO 16346, were developed to
form a uniform platform for calculation and evaluation of building energy performance. However, some
ambiguities still exist, due to lack of uniform specifications, such as the classification of energy usage,
the boundaries related to the energy data, and the basis of the aggregation methods. Hence, the present
International Standard is complementary to these International Standards on energy rating and energy
performance. It provides common rules for how to present the energy uses, as a uniform platform for
exchanging information, without prescribing what has to be measured or assessed as it is the case for
procedures aiming at energy performance assessment and certification.
At the same time, the relevant terms, definitions and symbols in ISO/TR 16344, such as space heating,
space cooling and domestic hot water heating, are incorporated by reference in the present International
Standard, so as to be consistent with the existing International Standards.
INTERNATIONAL STANDARD ISO 12655:2013(E)
Energy performance of buildings — Presentation of
measured energy use of buildings
1 Scope
This International Standard sets out a consistent methodology to present energy use in buildings, which
is specified clearly with the energy usage, corresponding boundary and the energy data (presented
with original energy carriers or equivalent energy).
This International Standard is applicable to the presentation of energy use of civil buildings for data
collection, metering, statistics, audit and analysis.
2 Normative references
The following referenced documents are indispensable for the application 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/TR 16344, Energy performance of buildings — Common terms, definitions and symbols for the overall
energy performance rating and certification
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/TR 16344 and the following apply.
3.1
building energy
energy used during the operation of buildings, including the energy used for building basic functions
and the energy provided for occupant’s activities
EXAMPLE Examples of occupant’s activities include working, cooking, leisure, sanitation, etc.
Note 1 to entry: The energy used during the manufacture of building materials, the energy for material
transportation and the energy during building construction are not included.
3.2
energy usage
specific usage of building energy
EXAMPLE Space heating, space cooling, domestic hot water, lighting, etc.
3.3
boundary
position in relation to the energy usage chain of buildings
3.4
equivalent energy
equivalent value of the energy carrier used in buildings to combine or share different energy carriers
with the same platform according to the standardized conversion approach
4 Building energy use defined by usage
4.1 Classification of building energy use by usage
According to the energy usage in buildings, as shown in Figure 1, the total building energy use shall be
classified as the following:
— Energy for HVAC and domestic hot water, including energy for space heating, energy for space
cooling, energy for air movement and energy for domestic hot water.
— Energy for lighting and plug-in, including energy for lighting and energy for household/office appliances.
— Energy for other ultimate usage, including energy for indoor transportation and energy for building
auxiliary devices.
— Energy for other special usage, including energy for cooking, energy for cooling storage, energy for
devices in data center and energy for other specific functional devices.
Space heating
Space cooling
HVAC and
domestic hot water
Domestic hot water
Air movement
Lighting
Lighting and plug-in
Household/ofice appliances
Total building
energy use
Indoor transportation
Other ultimate usage
Building auxiliary devices
Cooking
Cooling storage
Other special usage
Devices in data center
Other speciic functional devices
Figure 1 — The usage of energy in buildings
4.2 Energy for space heating
The energy used to provide heat (including humidification) for space heating of the building shall be
energy for space heating.
4.3 Energy for space cooling
The energy used to provide cold (including dehumidification) for space cooling of the building shall be
energy for space cooling.
4.4 Energy for air movement
The energy used by the mechanical ventilation fans for building ventilation and air circulation shall
be energy for air movement. It includes electricity consumed by fans inside air handling devices (air
2 © ISO 2013 – All rights reserved

handling unit, outdoor air processor, fan coil unit, etc.), exhaust fans in toilet, ventilation fans in the
garage and other ventilated spaces.
4.5 Energy for domestic hot water
The energy used to produce and transport hot water for building domestic water service shall be energy
for domestic hot water.
4.6 Energy for lighting
The energy used by the lamp(s), control gear and control circuit in or associated with the luminaries
shall be energy for lighting. It includes the indoor lighting and exterior lighting. The indoor lighting is
usually composed of lighting for public space and private space.
4.7 Energy for household/office appliances
The energy used by the household and office appliances, such as personal computers, printers, drinking
fountains and TVs, shall be energy for household/office appliances.
4.8 Energy for indoor transportation
The energy used by the indoor transportation devices in buildings, such as lifts, escalators and passenger
conveyors, shall be energy for indoor transportation.
4.9 Energy for building auxiliary devices
The energy used by all kinds of the building auxiliary devices that serve the building, such as pumps for
water supply and drainage, automatic door, shall be energy for building auxiliary devices.
4.10 Energy for cooking
The energy used for cooking inside a building shall be energy for cooking. It includes the fuel and
electricity consumed by cooking utensils and exhaust fans in the kitchen.
NOTE The energy used by the exhaust fans in the kitchen doesn’t belong to the item of energy for air
movement anymore.
4.11 Energy for cooling storage
The energy used by the refrigeration devices for storage shall be energy for cooling storage.
4.12 Energy for devices in data center
The energy used by the devices in data centers inside the building, including servers and ancillary air-
conditioning, shall be energy for devices in data center.
4.13 Energy for other specific functional devices
The energy used by other specific functional devices, such as medical equipment, laundry equipment
and auxiliary devices of swimming pool, shall be energy for other specific functional devices.
5 Building energy use defined by boundary
5.1 Identification of building energy use by boundary
Considering energy flow through the buildings, the building energy use shall be defined according to
boundary, and the categories are as follows:
— Heat/cold reaching the building space (E );
B
— Energy delivered to the building’s technical system (E );
T
— Energy input to the district heating/cooling system (E );
D
— Renewable energy produced on the building site (E ).
R
Schematic of the categories of building energy use determined by the boundaries mentioned above are
shown in Figure 2.
E E
T B
ED
District h
...