IEC GUIDE 118:2017

IEC GUIDE 118 ®
Edition 1.0 2017-03
GUIDE
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Inclusion of energy efficiency aspects in electrotechnical publications

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IEC GUIDE 118 ®
Edition 1.0 2017-03
GUIDE
colour
inside
Inclusion of energy efficiency aspects in electrotechnical publications

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.015 ISBN 978-2-8322-4115-8

– 2 – IEC GUIDE 118:2017 © IEC 2017
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Standardization and energy efficiency . 7
4.1 General considerations . 7
4.2 The concept of energy efficiency . 8
4.3 Systems approach . 9
4.4 Contribution of standardization to energy efficiency . 9
5 Energy efficiency aspects in IEC publications . 10
5.1 General . 10
5.2 Energy efficiency improvement process . 10
5.3 Inclusion of energy efficiency aspects in IEC publications . 11
5.4 Energy efficiency publications . 13
Annex A (informative) Market barriers to energy efficiency . 14
Annex B (informative) Engineering approach to energy efficiency improvement . 16
B.1 General . 16
B.2 Boundary definition . 16
B.2.1 Principle . 16
B.2.2 Explanation . 16
B.3 Loss identification . 17
B.3.1 Principle . 17
B.3.2 Explanation . 17
B.4 Loss estimation . 17
B.4.1 Principle . 17
B.4.2 Explanation . 17
B.5 Loss evaluation . 18
B.5.1 Principle . 18
B.5.2 Explanation . 18
B.6 Energy efficiency improvement . 19
B.6.1 Principle . 19
B.6.2 Explanation . 19
Annex C (informative) Inclusion of energy efficiency aspects in IEC publications . 20
Bibliography . 23

Figure 1 – Key elements in energy efficiency definition . 9
Figure 2 – Iterative process of energy efficiency improvement . 11

Table 1 – Energy efficiency aspect categories and examples . 12
Table A.1 – Examples of generic market barriers to energy efficiency and possible
measures to overcome them from a standardization point of view . 15
Table C.1 – Energy efficiency aspects and examples of their inclusion in publications . 20

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INCLUSION OF ENERGY EFFICIENCY ASPECTS
IN ELECTROTECHNICAL PUBLICATIONS

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
This first edition of IEC Guide 118 has been prepared, in accordance with ISO/IEC Directives,
Part 1, Annex A, by the IEC Advisory Committee on Energy Efficiency (ACEE). This is a non-
mandatory guide in accordance with SMB Decision 136/8.
The text of this IEC Guide is based on the following documents:
Four months' vote Report on voting
C/1979A/DV C/2002/RV
Full information on the voting for the approval of this IEC Guide can be found in the report on
voting indicated in the above table.

– 4 – IEC GUIDE 118:2017 © IEC 2017
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A bilingual version of this publication may be issued at a later date.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
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INTRODUCTION
Energy efficiency is key to addressing the challenge to support energy policies while
preserving the environment.
Many energy efficient technologies and solutions are already available and cost-effective;
nevertheless, a variety of barriers inhibits the deployment of these technologies and impedes
harvesting their energy efficiency potential.
Standardization can play an important role to help overcome these barriers and to
disseminate and promote energy efficient technologies, solutions and services.
This Guide aims to give advice to technical committees on the way energy efficiency should
be considered and included in IEC publications.
IEC publications may deal exclusively with energy efficiency or may include clauses specific
to energy efficiency; however technical committees are encouraged to:
• consider energy efficiency in their standardization work;
• identify which aspects of energy efficiency are relevant for their standardization;
• use a structured approach when addressing energy efficiency;
• use a systems approach when addressing energy efficiency.
This Guide helps to fulfil IEC Energy Efficiency Policy by indicating how energy efficiency
can be included in electrotechnical publications.
In this Guide, the term “technical committees” also includes subcommittees and system
committees. The term “publication” includes “International Standard”, “Technical Report”,
“Technical Specification” and “Guide”. In addition, the term “product” includes “process”,
“service” and combinations thereof, commonly known as “systems”.
Technical committees dealing with subjects relating to energy efficiency for the whole, or for a
specific part of their activities, are invited by SMB Decision 136/8 to follow the provisions of
this Guide.
___________
White Paper: Coping with the Energy Challenge. The IEC’s role from 2010 to 2030. Smart electrification – The
key to energy efficiency.
– 6 – IEC GUIDE 118:2017 © IEC 2017
INCLUSION OF ENERGY EFFICIENCY ASPECTS
IN ELECTROTECHNICAL PUBLICATIONS

1 Scope
This Guide is intended for technical committees and gives guidance on how to consider
energy efficiency aspects when preparing IEC publications.
Its purpose is:
• to describe the contributions of IEC publications to energy efficiency;
• to describe the concept of an energy efficiency aspect;
• to provide categories of energy efficiency aspects and a list of energy efficiency aspects to
be considered by technical committees.
This Guide:
• helps in harmonizing the approach to energy efficiency;
• raises awareness that provisions in IEC publications can affect the energy performance of
the product itself (taken individually) and of the entire application (embedding the
product), in both negative and positive ways;
• helps technical committees to identify energy efficiency aspects that contribute to energy
efficiency improvement of the product itself and of the entire application;
• promotes the use of a systematic approach when addressing energy efficiency in the
context of standardization;
• promotes the use of a systems approach when addressing energy efficiency aspects in the
context of standardization.
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/IEC 13273-1:2015, Energy efficiency and renewable energy sources – Common
international terminology – Part 1: Energy efficiency
lEC Guide 119, Preparation of energy efficiency publications and use of basic energy
efficiency publications and group energy efficiency publications
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC 13273-1 and
the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
energy efficiency
ratio or other quantitative relationship between an output of performance, service, goods or
energy, and an input of energy
EXAMPLE Conversion efficiency; 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/IEC 13273-1:2015, 3.4.1]
3.2
energy performance
measurable results related to energy efficiency, energy use and energy consumption
[SOURCE: ISO/IEC 13273-1:2015, 3.3.1]
3.3
energy efficiency improvement
increase in energy efficiency as a result of technological, design, behavioural or economic
changes
[SOURCE: ISO/IEC 13273-1:2015, 3.4.3]
3.4
relevant variable
quantifiable factor that impacts energy performance and routinely changes
EXAMPLE Production parameters (production, volume, production rate); weather conditions (outdoor temperature,
degree days); operating hours; operating parameters (operational temperature, light level).
[SOURCE: ISO 50006:2014, 3.14]
3.5
static factor
identified factor that impacts energy performance and does not routinely change
EXAMPLE 1 Facility size; design of installed equipment; the number of weekly production shifts; the number or
type of occupants (e.g. office workers); range of products.
EXAMPLE 2 A change of a static factor could be a change in manufacturing process raw material, from aluminium
to plastic.
[SOURCE: ISO 50006:2014, 3.17]
4 Standardization and energy efficiency
4.1 General considerations
Standardization plays a key role in promoting energy efficiency as it:
• supports the dissemination of energy efficient technologies;
• accelerates the uptake of the next generation of energy efficient technologies;

– 8 – IEC GUIDE 118:2017 © IEC 2017
• creates the prerequisites for energy efficiency through enabling technologies;
• enables conformity assessment;
• helps overcome market barriers to energy efficiency.
Energy efficiency is a horizontal topic spanning the IEC domain and may be dealt with in IEC
publications in various forms across a wide range of technologies and for different products,
processes and services.
The horizontal nature of the topic and increasing integration of products, processes and
services entering the market requires that technical committees identify which aspects of
energy efficiency are relevant for standardization and when doing that:
• use a structured approach;
• adopt a systems approach (see 4.3 and lEC Guide 119).
4.2 The concept of energy efficiency
Energy efficiency relates the output of an activity to its energy input, for a given service. The
input can be expressed in various energy units (kilowatt-hours, joules, tonnes of oil
equivalent, etc.). In contrast, the output may not necessarily be expressed in energy units and
covers a wide range of activities and services – production of cement, floor area,
passenger-kilometres, employees, etc. – expressed in many units (tonnes, square metres,
kilometres, number of employees, etc.).
It is key for energy efficiency to not reduce the given service but to optimize the energy input
for a given service.
NOTE 1 Examples of an activity include processes, services, etc.
NOTE 2 Energy performance and energy efficiency are different concepts. The concept of energy performance
includes energy use and energy consumption; energy performance, for instance, can be improved without
necessarily affecting energy efficiency. Energy efficiency is one aspect of energy performance and is a frequently
used metric for measuring energy performance.
NOTE 3 Implementation of energy efficiency measures can be based on energy price consideration.
Evaluation of energy efficiency should consider several important factors. Crucial are
boundaries which define the scope for energy efficiency improvement.
The description of the boundaries may be conceptual or physical.
In evaluating energy efficiency, all relevant energy inputs and outputs across the boundaries
need to be identified as well as the key performance indicators (KPIs) used to measure it.
For the complete definition of the context necessary for energy efficiency assessment, driving
parameters should also be defined (see Figure 1).
NOTE 4 Driving parameters, other than internal process parameters, are all factors that affect energy efficiency
and include weather, operating parameters (indoor temperature, lighting levels, etc.), production volume, range of
products, etc.; this concept includes the concept of relevant variable and static factors as defined by ISO 50006.
The definition of energy efficiency may vary when boundaries change.
EXAMPLE The energy efficiency of an electric motor, the energy efficiency of that motor driving a pump, the
energy efficiency of the pumping system made of that motor and pump.

BOUNDARY
KPIs for EE
OUTPUT
INPUT
KPIs for EE
DRIVING PARAMETERS
IEC
Figure 1 – Key elements in energy efficiency definition
For more details on boundary definition, see Clause B.2 and refer to lEC Guide 119.
Energy efficiency may vary and degrade over time.
4.3 Systems approach
Energy efficiency of a system needs to be analysed using a systems approach.
A systems approach to energy efficiency does not only consider the energy performance of
the single components, but, and essentially, how efficiently these components are used within
the application and boundary.
A systems approach to energy efficiency implies that the energy efficiency of one or more
components may be de-optimized in order to achieve the maximum efficiency in the
considered application and boundary.
A systems approach to energy efficiency is likely to optimize energy efficiency improvements
as:
• the components and the application are considered together;
• the gains in energy efficiency of an optimized system may be much higher than the gains
of an optimized individual component;
• an energy efficiency improvement at component level can be totally spoiled if this high
efficiency component is used in poor operating conditions.
4.4 Contribution of standardization to energy efficiency
Standardization can play a role in overcoming some of the barriers to the implementation of
energy efficient technologies and solutions. Examples include:
• common measurement and test methods to assess the use of energy and reductions
attained through new technologies and processes;
• calculation methods so that sound comparisons of alternatives can be made in specific
situations and can help with adaptation of infrastructure to integrate new technologies and
interoperability;
• means to codify best practices and management processes for efficient energy use and
energy conservation;
• design checklists and guides that can be applied to both the design of new systems as
well as the retrofit of existing systems;

– 10 – IEC GUIDE 118:2017 © IEC 2017
• common efficiency classifications, tolerances and minimum energy performance
standards;
• the definition of possible energy efficiency metrics.
When developing IEC publications, barriers to energy efficiency should be considered, with
the goal to contribute in overcoming such barriers through standardization activity. Annex A
provides examples.
5 Energy efficiency aspects in IEC publications
5.1 General
This Guide proposes a systematic procedure for the identification of energy efficiency aspects
to be considered for inclusion in IEC publications, when this is relevant for the technical
committees.
This procedure is based on a general description of the energy efficiency improvement
process. In this context, energy efficiency aspects are elements that are necessary to support
this process. Energy efficiency aspects include tools, methods, activities, measures,
checklists or guides.
Although this Guide is intended for use by technical committees, the principles of this
procedure are general and may be used whenever improving energy efficiency is being
considered during the life cycle.
5.2 Energy efficiency improvement process
A process to achieving energy efficiency improvements is shown in Figure 2.
In this energy efficiency improvement process as well as in the whole document the term
"loss" is not to be interpreted solely in strict physical terms nor with a negative connotation
only. The term "loss" includes also any kind of opportunity for energy efficiency improvement
which is currently not implemented.

START
BOUNDARY
DEFINITION
LOSS
IDENTIFICATION
ENERGY EFFICIENCY
LOSS
IMPROVEMENT
ESTIMATION
LOSS
EVALUATION
NO YES
LOSS
END
TOLERABLE?
IEC
Figure 2 – Iterative process of energy efficiency improvement
Starting with the boundary description, current energy efficiency can be determined and
potential improvements identified.
Once sources of losses are identified and their level determined (loss analysis), this can be
compared against a limit in order to determine whether such a level of losses is tolerable. If
they are not tolerable (e.g. according to classification level), energy efficiency improvement
should be implemented. Otherwise the process requires no further action. If the boundary or
the major parameters change, the process should be repeated.
The criteria for deciding whether the current level of losses is tolerable or not may be found in
many different sources such as national regulations, societal decisions or standards.
Annex B provides additional information.
5.3 Inclusion of energy efficiency aspects in IEC publications
Energy efficiency aspects are all elements that are necessary for the energy efficiency
improvement process described in 5.2.
It is the task of technical committees to identify and support all necessary energy efficiency
aspects in their publications.
Every proposal for preparing or revising a publication should identify which aspects of energy
efficiency are to be included.
The following categories of energy efficiency aspects should be considered (not all of these
may be relevant to a given publication):
• define energy efficiency;
• measure energy efficiency;
• assess energy efficiency;
• improve energy efficiency;
• enable energy efficiency.
LOSS ANALYSIS
LOSS ASSESSMENT
– 12 – IEC GUIDE 118:2017 © IEC 2017
Examples of energy efficiency aspects and energy efficiency aspect categories are presented
in Table 1. Annex C provides additional information on the inclusion of energy efficiency
aspects in IEC publications.
Table 1 – Energy efficiency aspect categories and examples
Energy efficiency aspect Energy efficiency aspect
categories
Define terminology
Define system boundaries (including the scope for energy efficiency)
Define EE KPIs (energy efficiency key performance indicators)
Define energy baseline
Define energy efficiency
Define driving parameters (adjustment factors, static factors)
Define reference applications
Define reference load profiles
Define reference c
...