IEC 62282-8-301:2023

Fuel cell technologies - Part 8-301: Energy storage systems using fuel cell modules in reverse mode - Power-to-methane energy systems based on solid oxide cells including reversible operation - Performance test methods

IEC 62282-8-301:2023 specifies performance test methods of power-to-methane systems based on solid oxide cells (SOCs). Water, CO2, and electricity are supplied to the system to produce methane and oxygen.
This document is not intended to be applied to solid oxide fuel cell (SOFC) cell/stack assembly units for power generation purposes only, since these are covered in IEC 62282-7-2. In addition, the test methods for SOC cell/stack assembly units including reversible operation (without any methanation reactor) are already described in IEC 62282-8-101.
This document is intended to be used for data exchanges in commercial transactions between the system manufacturers and customers. Users of this document can selectively execute test items suitable for their purposes from those described in this document.

Technologies des piles à combustible - Partie 8-301: Systèmes de stockage de l’énergie utilisant des modules à piles à combustible en mode inversé - Systèmes de conversion de l’énergie en méthane à base de piles à oxyde solide, comprenant le fonctionnement réversible - Méthodes d’essai des performances

IEC 62282-8-31:2023 spécifie les méthodes d’essai de performance des systèmes de conversion d’électricité en méthane à base de piles à oxyde solide (SOC). De l’eau, du CO2 et de l’électricité sont fournis au système pour produire du méthane et de l’oxygène.
IEC 62282 spécifie les méthodes d’essai de performance des systèmes de conversion d’électricité en méthane à base de piles à oxyde solide (SOC). De l’eau, du CO2 et de l’électricité sont fournis au système pour produire du méthane et de l’oxygène.
Le présent document est destiné à être utilisé pour les échanges de données dans le cadre de transactions commerciales entre les fabricants de systèmes et les clients. Les utilisateurs du présent document peuvent choisir les éléments d’essai à exécuter selon leurs objectifs parmi ceux décrits dans le présent document.

General Information

• Status: Published
• Publication Date: 22-May-2023
• ICS: 27.070 - Fuel cells
• Technical Committee: TC 105 - Fuel cell technologies
• Drafting Committee: WG 211 - TC 105/WG 211
• Current Stage: PPUB - Publication issued
• Start Date: 26-May-2023
• Completion Date: 23-May-2023

Standards Content (Sample)

IEC 62282-8-301
®

Edition 1.0 2023-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Fuel cell technologies –
Part 8-301: Energy storage systems using fuel cell modules in reverse mode –
Power-to-methane energy systems based on solid oxide cells including
reversible operation – Performance test methods

Technologies des piles à combustible –
Partie 8-301: Systèmes de stockage de l’énergie utilisant des modules à piles à
combustible en mode inversé – Systèmes de conversion de l’énergie en
méthane à base de piles à oxyde solide, comprenant le fonctionnement
réversible – Méthodes d’essai des performances
IEC 62282-8-301:2023-05(en-fr)

---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 62282-8-301

®


Edition 1.0 2023-05




INTERNATIONAL



STANDARD




NORME


INTERNATIONALE











Fuel cell technologies –

Part 8-301: Energy storage systems using fuel cell modules in reverse mode –

Power-to-methane energy systems based on solid oxide cells including

reversible operation – Performance test methods



Technologies des piles à combustible –


Partie 8-301: Systèmes de stockage de l’énergie utilisant des modules à piles à

combustible en mode inversé – Systèmes de conversion de l’énergie en

méthane à base de piles à oxyde solide, comprenant le fonctionnement


réversible – Méthodes d’essai des performances








INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE





ICS 27.070  ISBN 978-2-8322-6860-5




Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 3 ----------------------
– 2 – IEC 62282-8-301:2023 © IEC 2023
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 7
3 Terms, definitions, abbreviated terms and symbols . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms and symbols . 13
3.2.1 Abbreviated terms . 13
3.2.2 Symbols . 13
4 Power-to-methane system based on SOC . 18
5 Reference conditions . 19
5.1 Temperature and pressure . 19
5.2 Heating value base . 19
6 Instrumentation and measurement methods. 19
6.1 General . 19
6.2 Instrument uncertainty . 20
6.3 Measurement methods . 21
6.3.1 Measurement methods for testing the power-to-methane energy system . 21
6.3.2 Measurement methods for testing components . 24
7 Test methods and procedures. 27
7.1 General . 27
7.2 System performance tests . 27
7.2.1 Start-up test. 27
7.2.2 Performance tests at rated operation . 28
7.2.3 Performance test at power input variation . 32
7.2.4 Shutdown test . 33
7.3 Performance test for components. 33
7.3.1 SOC cell/stack assembly unit . 33
7.3.2 Methanation reactor . 42
8 Test report . 45
8.1 General . 45
8.2 Title page . 45
8.3 Table of contents . 45
8.4 Summary report . 46
Annex A (informative) Guidelines for the contents of detailed and full reports . 47
A.1 General . 47
A.2 Detailed report . 47
A.3 Full report . 47
Bibliography . 48

Figure 1 – Process schematic of the scope of IEC 62282-8-301 . 7
Figure 2 – Schematic of the physical interfaces of the system . 20
Figure 3 – Testing system . 34
Figure 4 – Test environment and interfaces between SOC cell/stack, methanation
reactor and experimental set-up . 36

Table 1 – Symbols . 13

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IEC 62282-8-301:2023 © IEC 2023 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

FUEL CELL TECHNOLOGIES –

Part 8-301: Energy storage systems using fuel cell modules in reverse
mode – Power-to-methane energy systems based on solid oxide cells
including reversible operation – Performance test methods

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,
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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.
IEC 62282-8-301 has been prepared by IEC technical committee 105: Fuel cell technologies.
It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
105/968/FDIS 105/983/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.

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– 4 – IEC 62282-8-301:2023 © IEC 2023
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 62282 series, published under the general title Fuel cell technologies,
can be found on the IEC website.
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,
• replaced by a revised edition, or
• amended.

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IEC 62282-8-301:2023 © IEC 2023 – 5 –
INTRODUCTION
This part of IEC 62282 describes performance evaluation methods for electric energy
conversion systems based on power-to-methane systems using solid oxide cells (SOCs) and
methanation reactors.
A typical application of the power-to-methane systems is an electrolytic production of methane
as the energy carrier suitable for a large-scale, long-term storage and transportation.
The combustion heat of methane per mol is about three times larger than that of hydrogen.
Methane is easily liquefied, which makes it suitable for storage and transportation via existing
infrastructures for natural gas (tanks, pipelines, tankers, or trucks) as well as for being easily
utilized by conventional equipment. Also, the use of "green methane" (produced by renewable
electricity) or "carbon neutral methane" in place of "fossil methane" is a promising option in the
near future.
The IEC 62282-8 series aims to develop performance test methods for power storage and
buffering systems based on electrochemical modules (combining electrolysis and fuel cells, in
particular reversible cells), taking into consideration both options of re-electrification and
substance (and heat) production for the sustainable integration of renewable energy sources.
Under the general title "Energy storage systems using fuel cell modules in reverse mode", the
IEC 62282-8 series consists of the following parts:
• IEC 62282-8-101: Test procedures for the performance of solid oxide single cells and
stacks, including reversible operation
• IEC 62282-8-102: Test procedures for the performance of single cells and stacks with proton
exchange membrane, including reversible operation
1
• IEC 62282-8-103 : Alkaline single cell and stack performance including reversible operation
2
• IEC 62282-8-201 : Test procedures for the performance of power-to-power systems
3
• IEC 62282-8-202 : Power-to-power systems – Safety
• IEC 62282-8-3xy (all parts): Power-to-substance systems
As a priority dictated by the emerging needs for industry and the opportunities for technological
development, IEC 62282-8-101, IEC 62282-8-102 and IEC 62282-8-201 were initiated jointly.
This document is the first of the IEC 62282-8-3xy series.


___________
1
 Under consideration.
2
 Second edition under preparation. Stage at the time of publication: IEC CDV 62282-8-201:2023.
3
 Under consideration.

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– 6 – IEC 62282-8-301:2023 © IEC 2023
FUEL CELL TECHNOLOGIES –

Part 8-301: Energy storage systems using fuel cell modules in reverse
mode – Power-to-methane energy systems based on solid oxide cells
including reversible operation – Performance test methods



1 Scope
This part of IEC 62282 specifies performance test methods of power-to-methane systems based
on solid oxide cells (SOCs). Water, CO , and electricity are supplied to the system to produce
2
methane and oxygen.
This document is not intended to be applied to solid oxide fuel cell (SOFC) cell/stack assembly
units for power generation purposes only, since these are covered in IEC 62282-7-2. In addition,
the test methods for SOC cell/stack assembly units including reversible operation (without any
methanation reactor) are already described in IEC 62282-8-101. Users can substitute the
selected test methods of this document with the equivalent test methods given in
IEC 62282-8-101 (solid oxide electrolysis cell (SOEC) to produce H only as well as SOFC
2
operation mode and reversible mode) and in IEC 62282-7-2 (SOFC mode only).
This document covers two types of processes as shown in Figure 1:
• Case 1: Steam and CO are introduced into the SOC (co-electrolysis process), and the
2
product gas (mainly, H + CO) is supplied to a methanation reactor (catalytic reactor);
2
• Case 2: Steam is introduced into the SOC to generate H , which is supplied into a
2
methanation reactor with CO .
2
Besides these two cases, the methanation catalyst can be integrated within the SOC, but this
case is not within the scope of this document. This document provides, for testing systems,
information on instruments and specifies measurement methods to test the performance of SOC
cell/stack assembly units and of the methanation reactor for energy conversion purposes. To
produce CH from water and CO , the SOC is operated in electrolysis mode (solid oxide
4 2
electrolysis cell (SOEC)). The SOC can be operated either in fuel cell mode (SOFC) or in
reversible operation mode or both. In this document, the system is considered not to have
components which store electricity, fluids, or heat.
This document is intended to be used for data exchanges in commercial transactions between
the system manufacturers and customers. Users of this document can selectively execute test
items suitable for their purposes from those described in this document.

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IEC 62282-8-301:2023 © IEC 2023 – 7 –

Figure 1 – Process schematic of the scope of IEC 62282-8-301
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.
IEC 60584-1, Thermocouples – Part 1: EMF specifications and tolerances
IEC 60584-3, Thermocouples – Part 3: Extension and compensating cables – Tolerances and
identification system
IEC 61515, Mineral insulated metal-sheathed thermocouple cables and thermocouples
IEC 62282-7-2:2021, Fuel cell technologies – Part 7-2: Test methods – Single cell and stack
performance tests for solid oxide fuel cells (SOFC)
IEC 62282-8-101:2020, Fuel cell technologies – Part 8-101: Energy storage systems using fuel
cell modules in reverse mode – Test procedures for the performance of solid oxide single cells
and stacks, including reversible operation
ISO 5167-1, Measurement of fluid flow by means of pressure differential devices inserted in
circular cross-section conduits running full – Part 1: General principles and requirements
ISO 5168, Measurement of fluid flow – Procedures for the evaluation of uncertainties
ISO 6141, Gas analysis – Contents of certificates for calibration gas mixtures
ISO 6142-1, Gas analysis – Preparation of calibration gas mixtures – Part 1: Gravimetric
method for Class I mixtures
ISO 6143, Gas analysis – Comparison methods for determining and checking the composition
of calibration gas mixtures
ISO 6145-7, Gas analysis – Preparation of calibration gas mixtures using dynamic methods –
Part 7: Thermal mass-flow controllers

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– 8 – IEC 62282-8-301:2023 © IEC 2023
ISO 6974 (all parts), Natural gas – Determination of composition and associated uncertainty by
gas chromatography
ISO 6975, Natural gas – Extended analysis – Gas-chromatographic method
ISO 7066-2, Assessment of uncertainty in the calibration and use of flow measurement devices
– Part 2: Non-linear calibration relationships
ISO 8573-1, Compressed air – Part 1: Contaminants and purity classes
ISO 8756, Air quality – Handling of temperature, pressure and humidity data
ISO 10101 (all parts), Natural gas – Determination of water by the Karl Fischer method
ISO 11541, Natural gas – Determination of water content at high pressure
3 Terms, definitions, abbreviated terms and symbols
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
active electrode area
effective electrode area
geometric area of the electrode where the electrochemical reaction takes place
Note 1 to entry: Usually this corresponds to the smaller of the two areas of negative electrode or positive electrode.
2 2
Note 2 to entry: Area perpendicular to the ionic current flow, usually expressed in m or cm .
[SOURCE: IEC 62282-8-101:2020, 3.1.1]
3.1.2
additional gas
gas added to the product gas from the negative electrode for the reaction in the methanation
reactor
Note 1 to entry: For Case 2 in Figure 1, the additional gas is CO .
2
Note 2 to entry: For Case 1 in Figure 1 (co-electrolysis mode), CO or H or both can be added to convert the
2 2
product gas from the negative electrode into CH efficiently.
4
3.1.3
area-specific resistance
ASR
internal resistivity of any component of a cell or a stack, including the change of potential due
to the electrochemical reaction
2 2
Note 1 to entry: It is normalized by the active electrode area and is expressed in Ω · m or Ω · cm .
[SOURCE: IEC 62282-8-101:2020, 3.1.2]

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IEC 62282-8-301:2023 © IEC 2023 – 9 –
3.1.4
catalyst
substance that accelerates a reaction without being consumed itself
[SOURCE: IEC 60050-485:2020, 485-01-01, modified – "electrochemical reaction" has been
replaced by "reaction" and Note 1 and Note 2 have been deleted.]
3.1.5
cell
single cell
basic unit of a solid oxide cell
[SOURCE: IEC 62282-8-101:2020, 3.1.7, modified – "cell" has become a preferred term.]
3.1.6
cold state
state of a power-to-methane system at ambient temperature with no power input or output
Note 1 to entry: The cold state can come after the storage state during cooling-down of the system.
[SOURCE: IEC 60050-485:2020, 485-21-01, modified – "fuel cell power system" has been
replaced by "power-to-methane system" and the Note to entry has been added.]
3.1.7
compression force
axial load
compressive load applied to the single cell or to the end plates of a planar SOC stack to ensure
electric contact and gas tightness
Note 1 to entry: The compression force is in practice expressed in N.
[SOURCE: IEC 62282-8-101:2020, 3.1.7, modified – The preferred term "axial load" has
become an admitted term and the admitted term "compression force" has become a preferred
term.]
3.1.8
conditioning
preliminary step of treatment that is required to properly operate a SOC and is usually realized
by following a protocol specified by the manufacturer
[SOURCE: IEC 62282-8-101:2020, 3.1.8, modified – The Note 1 to entry has been deleted.]
3.1.9
conversion of CO into CH
2 4
catalytic conversion percentage of carbon dioxide into methane in the methanation reactor
3.1.10
conversion of H into CH
2 4
catalytic conversion percentage of hydrogen into methane in the methanation reactor
3.1.11
current density
electric current per unit active area of the electrode
2 2
Note 1 to entry: The current density is expressed in A/m or A/cm .
[SOURCE: IEC 60050-485:2020, 485-12-01, modified – "of the electrode" has been added and
the domain has been deleted.]

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– 10 – IEC 62282-8-301:2023 © IEC 2023
3.1.12
electrode gas
gas present at the positive or negative electrode
Note 1 to entry: Electrode gases can be reactants, products or inert gas.
[SOURCE: IEC 62282-8-101:2020, 3.1.14]
3.1.13
interconnector
interconnect
electronically conductive and gas-tight component connecting single cells in a stack
[SOURCE: IEC 62282-8-101:2020, 3.1.4, modified – "electronically" has been added and the
Notes to entry have been deleted.]
3.1.14
methanation reactor
catalytic reactor which converts CO , CO, and H into CH
2 2 4
3.1.15
negative electrode
electrode at which fuel (reductant) gas is consumed or produced
Note 1 to entry: In the case of electrolysis mode with an oxide-ion conducting electrolyte such as yttria-stabilized
zirconia in a SOC, steam is reduced to produce hydrogen or a mixture of steam and CO is reduced to produce H +
2 2
CO.
Note 2 to entry: In the case of electrolysis mode for a proton conducting SOC, the negative electrode gas is
hydrogen or inert gas or both (Case 2 in Figure 1) or a mixture of hydrogen, CO and inert gas (Case 1, co-
2
electrolysis).
[SOURCE: IEC 62282-8-101:2020, 3.1.19, modified – "(reductant)" has been added and the
three Notes to entry have been replaced with two new Notes to entry.]
3.1.16
positive electrode
electrode at which oxygen is consumed or produced
Note 1 to entry: In the case of electrolysis mode for an oxide-ion conducting SOC, the positive electrode gas is
usually air to carry the generated oxygen.
Note 2 to entry: In the case of electrolysis mode for a proton conducting SOC, the
...