IEC 62746-4:2024

Systems interface between customer energy management system and the power management system - Part 4: Demand Side Resource Interface

IEC 62746-4:2024 describes CIM profiles for Demand-Side Resource Interface and is based on the use case shown in Annex A of this document. Schemas associated with this document were generated using the CIM101 UML and leverages the Market package. This document defines profiles complimentary to other standards, namely those in IEC 61970, IEC 61968, and IEC 62325.

Interface entre le système de gestion de l'énergie côté client et le système de gestion de puissance - Partie 4: Interface de ressources côté demande

L'IEC 62746-4:2024 décrit les profils CIM pour l'interface de ressources côté demande et repose sur le cas d'utilisation donné à l'Annexe A du présent document. Les schémas associés au présent document ont été générés à l'aide du CIM101 UML et utilisent le paquetage Market. Le présent document définit des profils qui viennent compléter ceux d'autres normes, à savoir l'IEC 61970, l'IEC 61968 et l'IEC 62325.

General Information

• Status: Published
• Publication Date: 19-Dec-2024
• ICS: 33.200 - Telecontrol. Telemetering
• Technical Committee: TC 57 - Power systems management and associated information exchange
• Drafting Committee: WG 21 - TC 57/WG 21
• Current Stage: PPUB - Publication issued
• Start Date: 20-Dec-2024
• Completion Date: 17-Jan-2025

Overview

IEC 62746-4:2024 is an international standard published by the International Electrotechnical Commission (IEC) that defines the system interface between Customer Energy Management Systems (CEMS) and Power Management Systems (PMS), with a focus on the Demand Side Resource Interface. This standard establishes Common Information Model (CIM) profiles tailored specifically for demand-side resource communication and management, supporting interoperability and efficient energy usage.

The standard builds upon use cases provided in Annex A and is developed using CIM101 UML schemas leveraging the Market package. IEC 62746-4:2024 complements related IEC standards such as IEC 61970, IEC 61968, and IEC 62325, ensuring a harmonized approach to energy management and market operations.

Key Topics

• CIM Profiles for Demand-Side Resources: Defines standardized profiles to facilitate exchange of information related to distributed energy resources (DERs), flexible loads, and other demand-side assets.
• Resource Modelling: Detailed models for resource location, capability, qualification, and operational status ensure clear representation of demand-side elements in the power system.
• Energy Scheduling and Bid/Offer Management: Supports schedules, bids, and offers for energy consumption and production from demand-side resources, enabling price-sensitive market participation.
• Dispatch and Control Messaging: Defines how dispatch instructions and operational controls are communicated between PMS and CEMS, supporting real-time demand response.
• Commodity and Price Modeling: Enables representation of energy commodities and associated pricing data to integrate demand-side resources into market mechanisms.
• Message Profiles and Sequences: Establishes message schemas and standardized communication sequences such as Inform, Incentivise, Plan, Schedule, and Report for effective coordination.
• Use Case Application: Includes an incentive-based building energy management scenario demonstrating practical implementations of the standard.

Applications

IEC 62746-4:2024 provides a robust framework for integrating demand-side energy resources into power system management. Key application areas include:

• Demand Response Programs: Enables utilities and aggregators to integrate flexible loads and DERs, optimizing load profiles and grid reliability.
• Energy Market Participation: Supports bid/offer submissions and price-based control of demand-side resources, promoting active participation of consumers in energy markets.
• Building Energy Management: Facilitates advanced control of energy consumption in commercial and residential buildings through standardized interfaces.
• Distributed Resource Aggregation: Offers models for stacking or aggregating multiple demand-side resources and managing them as single entities.
• Smart Grid Integration: Enhances communication and coordination in smart grid deployments by ensuring interoperable interfaces between customer systems and grid operators.
• Incentive-Based Control: Supports incentive mechanisms to encourage energy consumption shifts during peak periods.

Related Standards

IEC 62746-4:2024 is closely aligned and complementary to several other IEC and international standards, including:

• IEC 61970 - Energy Management System Application Program Interface (EMS-API): Provides core models for power system management.
• IEC 61968 - System Interfaces for Distribution Management: Focuses on utility distribution system integration.
• IEC 62325 - Framework for Energy Market Communications: Covers market-related communication profiles.
• CIM 101 UML - Foundation models used to define energy and market communication schemas leveraged in this standard.

This alignment ensures seamless integration, data consistency, and interoperability across various components within the energy ecosystem.

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By adhering to IEC 62746-4:2024, stakeholders such as energy utilities, equipment manufacturers, software developers, and regulatory bodies can advance demand-side management capabilities, optimize grid performance, and enhance customer engagement in energy markets. Implementing the standard supports smarter energy consumption patterns, cost savings, and a more sustainable energy future.

Standards Content (Sample)

IEC 62746-4 ®
Edition 1.0 2024-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Systems interface between customer energy management system and the power
management system –
Part 4: Demand Side Resource Interface

Interface entre le système de gestion de l'énergie côté client et le système de
gestion de puissance –
Partie 4: Interface de ressources côté demande
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IEC 62746-4 ®
Edition 1.0 2024-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Systems interface between customer energy management system and the

power management system –
Part 4: Demand Side Resource Interface

Interface entre le système de gestion de l'énergie côté client et le système de

gestion de puissance –
Partie 4: Interface de ressources côté demande

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.200 ISBN 978-2-8327-0099-0

– 2 – IEC 62746-4:2024 © IEC 2024
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Terms, definitions and acronyms . 9
3.1 Terms and definitions . 9
3.2 Acronyms . 11
4 Reference and information models . 11
4.1 General approach . 11
4.2 Reference communication model . 13
4.3 Information Model . 15
4.3.1 General . 15
4.3.2 Resource Modelling . 15
4.3.3 Resource location modelling . 17
4.3.4 Resource capability and qualification modelling . 19
4.3.5 Energy schedule modelling . 20
4.3.6 Bid/offer modelling . 22
4.3.7 Dispatch modelling . 23
4.3.8 Commodity and price modelling . 24
5 Core modelling and shared enumerations . 26
5.1 Master resource identifiers . 26
5.2 Compound classes . 27
5.2.1 General . 27
5.2.2 Compounds with quantity, unit symbols and unit multipliers . 27
5.2.3 Date/Time Interval Compound . 28
5.2.4 Status Compound . 28
5.2.5 Street address, street detail and town detail compounds . 28
5.2.6 Electronic address and telephone number compound . 29
5.2.7 Document & agreement classes . 30
5.2.8 Location, coordinate system & position point classes . 31
5.3 Shared data types . 32
6 Message Profiles . 35
6.1 General . 35
6.2 Market DER profile. 36
6.2.1 General . 36
6.2.2 Applications . 36
6.2.3 Schema . 36
6.3 Reference energy curve profile . 40
6.3.1 General . 40
6.3.2 Applications . 40
6.3.3 Schema . 41
6.4 Bid/offer curve profile . 44
6.4.1 General . 44
6.4.2 Applications . 44
6.4.3 Schema . 45
6.5 Dispatch Profile . 50

6.5.1 General . 50
6.5.2 Applications . 50
6.5.3 Schema . 50
6.6 Commodity price exchange profile . 53
6.6.1 General . 53
6.6.2 Applications . 53
6.6.3 Schema . 53
7 Message sequences . 55
7.1 General . 55
7.2 Inform . 57
7.3 Incentivise . 57
7.4 Plan . 57
7.5 Schedule. 57
7.6 Report. 57
7.7 Evaluate . 58
Annex A (informative) Use case: Incentive-based building energy management . 59
A.1 Overview. 59
A.2 Objectives . 59
A.3 Actors . 60
A.4 Process overview . 61
A.5 Process details . 63
A.5.1 Pre-setup condition notification . 63
A.5.2 Price notification and energy consumption plan notification . 64
A.5.3 Energy consumption assignment . 65
A.5.4 Operation report . 66
A.5.5 Suppression control . 67
A.6 Possibilities for control parameters . 68
A.7 Implementation using CIM Profiles defined in this document . 68
Annex B (normative) Profile UML diagrams . 69
Annex C (normative) XML schemas . 72
Annex D (informative) Sample XML . 73
Bibliography . 74

Figure 1 – IEC 62746-4 representation . 12
Figure 2 –SPS-CEMS communication logical model . 13
Figure 3 – SPS-AEMS-CEMS communications logical model . 14
Figure 4 – Example of "stacked" aggregators . 15
Figure 5 – Resource model . 16
Figure 6 – Location model . 17
Figure 7 – Node mapping . 18
Figure 8 – Connectivity and pricing / nodes & zones . 19
Figure 9 – Capacity and qualification model . 20
Figure 10 – Energy schedule model . 21
Figure 11 – Price-based versus self-schedule . 22
Figure 12 – Price-sensitive bids/offers . 23
Figure 13 – Dispatch model . 24

– 4 – IEC 62746-4:2024 © IEC 2024
Figure 14 – Commodity model . 25
Figure 15 – Price model . 26
Figure 16 – MarketDER schema . 37
Figure 17 – ResourceCapacity sub-schema . 39
Figure 18 – ResourceCertification sub-schema . 40
Figure 19 – Reference energy curve schema . 41
Figure 20 – ResourceTimeSeries sub-schema . 42
Figure 21 – Time Points sub-schema . 44
Figure 22 – Bid/offer curve schema . 45
Figure 23 – Product Bid sub-schema . 46
Figure 24 – Price-Sensitive Bid/offer sub-schema . 46
Figure 25 – BidPriceCurve Sub-Schema . 47
Figure 26 – CurveDatas sub-schema . 48
Figure 27 – BidSelfSched sub-schema . 48
Figure 28 – TimePoints sub-schema . 49
Figure 29 – MarketDERInstruction schema . 50
Figure 30 – DistributedResourceActualEvent sub-schema . 51
Figure 31 – InstructionClearing sub-schema . 52
Figure 32 – MarketOccurrence sub-schema . 53
Figure 33 – CommodityPriceExchange Schema . 54
Figure 34 – Commodity price schema . 55
Figure 35 – Sequence diagram . 56
Figure 36 – Examples of Energy Values for Demand Response Exchanges . 58
Figure A.1 – A configuration example of demand-side resource . 60
Figure A.2 – The whole view of this use case . 62
Figure A.3 – Pre-setup condition notification . 63
Figure A.4 – Price notification and energy consumption plan notification. 64
Figure A.5 – Energy consumption assignment . 65
Figure A.6 – Operation report . 66
Figure A.7 – Suppression control . 67
Figure B.1 – MarketDER . 69
Figure B.2 – ReferenceEnergyCurve . 70
Figure B.3 – MarketDERBidOffer . 70
Figure B.4 – MarketDERInstruction . 71
Figure B.5 – CommodityPriceExchange . 71

Table 1 – List of acronyms . 11
Table 2 – Attributes of IdentifiedObject . 26
Table 3 – Attributes of FloatQuantity . 27
Table 4 – Attributes of ActivePowerChangeRate . 27
Table 5 – Attributes of Seconds . 27
Table 6 – Attributes of Minutes . 27
Table 7 – Attributes of DateTimeInterval . 28

Table 8 – Attributes of Status . 28
Table 9 – Attributes of StreetAddress. 28
Table 10 – Attributes of StreetDetail . 29
Table 11 – Attributes of DownDetail . 29
Table 12 – Attributes of ElectronicAddress . 29
Table 13 – Attributes of TelephoneNumber . 30
Table 14 – Attributes of Document . 30
Table 15 – Attributes of Agreement . 30
Table 16 – Attributes of Location . 31
Table 17 – Attributes of CoordinateSystem . 31
Table 18 – Attributes of PositionPoint . 31
Table 19 – UnitSymbol & UnitMultiplier data types . 32
Table 20 – Yes/No, priority and currency data types . 32
Table 21 – Market-related enumerations . 33
Table 22 – Price-related enumerations . 33
Table 23 – Resource-related enumerations . 34
Table 24 – Scheduling-related enumerations . 35
Table 25 – Attributes of MarketDER . 38
Table 26 – Attributes of ResourceCapacity . 39
Table 27 – Attributes of ResourceCertification . 40
Table 28 – Attributes of ResourceTimeSeries . 43
Table 29 – Attributes of TimePoints . 44
Table 30 – Attributes of DistributedBid . 45
Table 31 – Attributes of ProductBid . 46
Table 32 – Attributes of BidSchedule . 47
Table 33 – Attributes of BidPriceCurve . 47
Table 34 – Attributes of CurveDatas . 48
Table 35 – Attributes of BidSelfScheduleAttribute . 49
Table 36 – Attributes of TimePoints . 49
Table 37 – Attributes of DistributedResourceEventActual . 51
Table 38 – Attributes of InstructionClearing . 52
Table 39 – Attributes of MarketOccurence . 53
Table 40 – Attributes of CommodityPriceExchange . 54
Table 41 – Attributes of CommodityPrice . 55
Table A.1 – Actors in this use case . 61
Table A.2 – Information Exchanged in Pre-setup condition notification . 63
Table A.3 – Information exchanged in price notification and energy consumption plan
notification . 65
Table A.4 – Information exchanged in energy consumption assignment . 66
Table A.5 – Information exchange in operation report . 67
Table A.6 – Information exchanged in suppression control . 68
Table A.7 – Mapping messages from this use case to CIM Profile . 68

– 6 – IEC 62746-4:2024 © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SYSTEMS INTERFACE BETWEEN
CUSTOMER ENERGY MANAGEMENT SYSTEM
AND THE POWER MANAGEMENT SYSTEM –

Part 4: Demand-side resource interface

FOREWORD
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IEC 62746-4 has been prepared by IEC technical committee 57: Power systems management
and associated information exchange. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
57/2719/FDIS 57/2746/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 62746 series, published under the general title Systems interface
between customer energy management system and the power management system, can be
found on the IEC website.
NOTE The following print types are used:
• UML classes are formatted using bold and italics, for example RegisteredResource.
• UML class attributes are formatted using italics, for example mRID.
• Message profile names are formatted using bold, for example MarketDER.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

– 8 – IEC 62746-4:2024 © IEC 2024
INTRODUCTION
The IEC 62746 series defines interfaces between grid operator systems and systems located
at residential, commercial, and industrial customer sites often referred to as Customer Energy
Management Systems (CEMs). These interfaces are documented in detail in IEC 62746-3.
Customer owned resources can be a combination of load and generation which respond to
signals provided by grid and/or market operators. These resources are identified and managed
as individual resources with specific capabilities, or as virtual resources with an aggregated set
of capabilities.
The IEC 62746 series describes the interface between Customer Energy Management Systems
(CEMs) and the grid management systems including those within Distribution System Operators
and Transmission System Operators. Each CEMS is designed to control resources associated
with a residential, commercial, or industrial facility with the potential for a hierarchy of energy
management systems.
Initial focus is on demand response and support for demand-side management; later
developments are expected to include storage resources as well as grid support services from
new demand-side resources. The interface applies to many types of communications, for
example among multiple aggregators, or between an aggregator and multiple customers.
Scenarios that publish import and/or export limits as part of a market-based systems or as part
of an operational reliability framework, sometimes known as operating envelopes, are also
supported.
This document describes CIM profiles corresponding to the Use Case described in Annex A.
Statements have been added to certain figures, tables, schemas, and enumerations throughout
the document that indicate that they are reproduced with the permission of the UCA
International User Group (UCAIug). These items are derived from the Common Information
Model (CIM).
SYSTEMS INTERFACE BETWEEN
CUSTOMER ENERGY MANAGEMENT SYSTEM
AND THE POWER MANAGEMENT SYSTEM –

Part 4: Demand-side resource interface

1 Scope
This part of the IEC 62746 series describes CIM profiles for Demand-Side Resource Interface
and is based on the use case shown in Annex A of this document.
Schemas associated with this document were generated using the CIM101 UML and leverages
the Market package. This document defines profiles complimentary to other standards, namely
those in IEC 61970, IEC 61968, and IEC 62325.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and acronyms
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
aggregation
collection of the capabilities of multiple resources into a single virtual resource
Note 1 to entry: A common use of aggregation is to collect many small resources and offer their capabilities in the
form of a single larger resource to a market.
[SOURCE: IEC 62746-3:2015, 3.1.1]
3.1.2
aggregator
party who contracts with a number of other network users (e.g. energy consumers) in order to
combine the effect of smaller loads or distributed energy resources for actions such as demand
response or for ancillary services
[SOURCE: IEC 60050-617:2009, 617-02-18]
3.1.3
aggregator energy management system
collection of hardware and/or software components which together act as an intermediary
between a Service Procurement System and multiple Customer Energy Management Systems

– 10 – IEC 62746-4:2024 © IEC 2024
3.1.4
customer energy management system
collection of hardware and/or software components which together coordinate the electricity
usage and production among various Distributed Energy Resources
3.1.5
demand response
action resulting from management of the electricity demand in response to supply conditions
[SOURCE: IEC 60050-617:2009, 617-04-16]
3.1.6
Distributed Energy Resource
Generators (with their auxiliaries, protection, and connection equipment), including loads
having a generating mode (such as electrical energy storage systems), connected to a low-
voltage or a medium-voltage network
Note 1 to entry: DER may include associated protection, control, and monitoring capabilities, and may consist of
aggregated DER units.
Note 2 to entry: DER may also interact with the area EPS (typically a distribution network) by providing energy to
the distribution network, by adapting their behaviour based on distribution network conditions, and/or by providing
other transmission and distribution network-related services.
[SOURCE: IEC 60050-617:2009, 617-04-20, modified – notes taken from IEC 61850-7-
420:2021, 3.1.13]
3.1.7
operator role
"upper" side of the DER communication chain, representing the entity which is responsible for
procuring services and distributing operational controls and prices
3.1.8
resource role
"lower" side of the DER communication chain, representing the entity which is responsible for
providing services and responding to operational controls and prices
3.1.9
service procurement system
collection of hardware and/or software component which together procure services to make the
electrical grid more reliable and/or less costly
3.1.10
technical role
role that identifies responsibilities associated with participation within information exchanges
with other actors
Note 1 to entry: Actors defined by use cases have assigned roles with associated responsibilities. Technical roles
are physically realized through software and associated systems integration infrastructure.
[SOURCE: IEC 62746-3:2015, 3.1.14]

3.1.11
virtual resource
set of one or more physical resources that is represented as a single, aggregated resource
Note 1 to entry: This may be comprised of multiple entities that may be geographically distributed. Virtual resources
can be an aggregated model of many types of loads, generation and storage, such as VPP, PV, factory, building,
home, etc. Since the virtual resource can include both energy consumer and energy provider, the related "net load
curve" can be positive (in this case the virtual resource acts as a consumer which consumes electrical power), or
negative (in this case the virtual resource acts as generation assets to produce electrical power).
[SOURCE: IEC 62746-3:2015, 3.1.16]
3.2 Acronyms
Table 1 contains a list of acronyms used in this document.
Table 1 – List of acronyms
Acronym Phrase
AEMS Aggregator Energy Management System
CEMS Customer Energy Management System
DAM Day-Ahead Market
DER Distributed Energy Resource
EPS Electrical Power System
PV Photovoltaic
RTM Real-Time Market
SPS Service Procurement System
UML Unified Modeling Language
VPP Virtual Power Plant
XML Extensible Markup Language
XSD XML Schema Definition
4 Reference and information models
4.1 General approach
Communications between electricity markets and grid operations are enabled by shared
modelling among three series of standards: IEC 61968, IEC 61970, and IEC 62325. However,
none of these standards extend into the domain of controllable resources deployed on the
distribution grid, and specifically to those resources "behind" the customer electricity meter.
IEC 62746 remedies this situation by providing a set of message profiles designed to convey
grid instructions, grid conditions, pricing signals, and resources capabilities among multiple
parties within the emerging Distributed Energy Resource (DER) space, as illustrated in Figure 1.

– 12 – IEC 62746-4:2024 © IEC 2024

Figure 1 – IEC 62746-4 representation
The communication requirements are challenging given the wide range of communicating
parties , including:
• Electricity market operators,
• Transmission system operators,
• Wholesale electricity service providers,
• Wholesale electricity service consumers,
• Distribution grid operators,
• Service aggregators, and
• Electricity consumers.
Additionally, there is a wide range of business processes which are established as well as many
new models being devised. These processes include the communication of the time-varying
changes in:
• Resource composition by grid location(s)
• Resource capability by market service
• Economic thresholds for service delivery/procurement
• Resource instructions/dispatches
The challenge of communicating with DERs (or their aggregators) can be visualized as a more
complex permutation of communication with traditional bulk-power electricity generation
stations. Therefore, IEC 62746-4 leverages the IEC 62325 series of standards which are
currently in use to standardize bulk-power market exchanges.
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For an explanation of these actors, see IEC 60050-617:2009, Organization/Market of electricity.

4.2 Reference communication model
This reference model has two technical roles: the Operator Role and the Resource Role. The
Operator Role, in the simplest configuration, is performed by a grid operator with any number
of applications which are used to track, manage, forecast, incentivize, control, and monitor
DERs. This collection of software we group as a single collection labelled the Service
Procurement System (SPS), as it has the responsibility of procuring grid services to make the
grid more reliable and/or make electricity costs lower. The distribution customer who owns a
DER takes on the Resource Role, with the collection of software controlling the customer's
facility termed the Customer Energy Management System (CEMS). Figure 2 illustrates the
logical model for these communications in this base configuration.

Figure 2 –SPS-CEMS communication logical model
Individual DERs may not be large enough to warrant direct participation in grid operations and
may be better served as members of a DER aggregation. When aggregation is introduced into
the communication chain, the Aggregator Energy Management System (AEMS) acts as
intermediary for communications between the SPS and many CEMSs. However, the AEMS is
not simply a broker of information; the AEMS performs aggregation functions (such as adding
together individual CEMS capabilities to pass to the SPS) and allocation functions (such as
dividing dispatch signals across the participating CEMSs). IEC 62746-4 is used on both ends
of the exchange, with the AEMS performing the Resource Role when communicating with the
SPS and the Operator Role when communicating with each CEMS, as shown in Figure 3. Thus,
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