Information technology - Data centre facilities and infrastructures - Part 4-8: Carbon usage effectiveness

This document specifies the Carbon Usage Effectiveness (CUE) as a KPI to qualify the CO2 emissions of a data centre during use phase of the data centre life cycle. By reporting CO2 emissions, it is possible to present the data centres contribution to climate change (enhanced greenhouse effect).

Informationstechnik - Einrichtungen und Infrastrukturen von Rechenzentren - Teil 4-8: Effektivität der Vermeidung von CO2-Emissionen

Technologie de l’information - Installation et infrastructures de centres de traitement de données - Partie 4-8: Efficacité de l’utilisation du carbone

Le présent document spécifie l’efficacité de l’utilisation du carbone comme un KPI permettant de quantifier les émissions de CO2 d’un centre de traitement de données pendant la phase d’utilisation du cycle de vie du centre de traitement de données.
Le présent document:
a)   définit l’efficacité de l’utilisation du carbone d’un centre de traitement de données;
b)   introduit les catégories de mesure de la CUE;
c)   décrit la relation de ce KPI avec une infrastructure de centre de traitement de données, des équipements de traitement de l’information et des opérations de traitement de l’information;
d)   définit le mesurage, le calcul et les rapports du paramètre;
e)   fournit des informations sur l’interprétation correcte de la CUE.

Informacijska tehnologija - Naprave in infrastruktura podatkovnega centra - 4-8. del: Učinkovitost porabe ogljika

Ta dokument določa učinkovitost porabe ogljika (CUE) kot KPI za opredelitev emisij CO2 podatkovnega centra med fazo uporabe življenjskega cikla podatkovnega centra. S poročanjem o emisijah CO2 je mogoče predstaviti prispevek podatkovnih centrov k podnebnim spremembam (okrepljen učinek tople grede).

General Information

Status
Published
Publication Date
16-Jan-2023
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
10-Jan-2023
Due Date
17-Mar-2023
Completion Date
17-Jan-2023

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SLOVENSKI STANDARD
SIST EN 50600-4-8:2023
01-marec-2023
Informacijska tehnologija - Naprave in infrastruktura podatkovnega centra - 4-8.
del: Učinkovitost porabe ogljika
Information technology - Data centre facilities and infrastructures - Part 4-8: Carbon
usage effectiveness
Informationstechnik - Einrichtungen und Infrastrukturen von Rechenzentren - Teil 4-8:
Effektivität der Vermeidung von CO2-Emissionen
Technologie de l’information - Installation et infrastructures de centres de traitement de
données - Partie 4-8: Efficacité de l’utilisation du carbone
Ta slovenski standard je istoveten z: EN 50600-4-8:2022
ICS:
13.020.99 Drugi standardi v zvezi z Other standards related to
varstvom okolja environmental protection
35.110 Omreževanje Networking
35.160 Mikroprocesorski sistemi Microprocessor systems
SIST EN 50600-4-8:2023 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 50600-4-8:2023

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SIST EN 50600-4-8:2023


EUROPEAN STANDARD EN 50600-4-8

NORME EUROPÉENNE

EUROPÄISCHE NORM December 2022
ICS 35.020; 35.110; 35.160
English Version
Information technology - Data centre facilities and infrastructures
- Part 4-8: Carbon usage effectiveness
Technologie de l'information - Installation et infrastructures Informationstechnik - Einrichtungen und Infrastrukturen von
de centres de traitement de données - Partie 4-8: Efficacité Rechenzentren - Teil 4-8: Effektivität der Vermeidung von
de l'utilisation du carbone CO2-Emissionen
This European Standard was approved by CENELEC on 2022-12-12. CENELEC 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 CENELEC 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.



European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN 50600-4-8:2022 E

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SIST EN 50600-4-8:2023
EN 50600-4-8:2022 (E)
Contents Page
European foreword . 4
Introduction . 5
1 Scope . 8
2 Normative references . 8
3 Terms, definitions, abbreviations and symbols . 8
3.1 Terms and definitions . 8
3.2 Abbreviations . 9
3.3 Symbols . 10
4 Applicable area of the data centre . 10
5 Determination of Carbon Usage Effectiveness . 11
6 Measurement of Carbon Usage Effectiveness . 11
6.1 General . 11
6.2 Calculation and measurement method of CO . 11
2
6.2.1 Calculation and measurement period and frequency . 11
6.2.2 Categories of Carbon Usage Effectiveness . 11
7 Application of Carbon Usage Effectiveness . 13
8 Reporting of Carbon Usage Effectiveness . 13
8.1 Requirements . 13
8.1.1 Standard construct for communicating CUE data . 13
8.1.2 Data for public reporting of CUE . 13
8.2 Recommendations . 14
8.2.1 Trend tracking data . 14
8.3 Example of reporting CUE values . 15
8.4 CUE derivatives . 15
8.4.1 Purpose of CUE derivatives . 15
8.4.2 Using CUE derivatives . 15
8.4.3 Interim CUE. 16
8.4.4 Partial CUE . 16
8.4.5 Design CUE . 16
Annex A (informative) Examples of use . 17
A.1 Correct use of CUE . 17
A.2 Carbon Usage Effectiveness category 1 . 17
A.3 Carbon Usage Effectiveness category 2 . 18
A.4 Carbon Usage Effectiveness category 3 . 18
A.5 Interim Carbon Usage Effectiveness category 2 . 18
Annex B (informative) Energy conversion factors . 20
Annex C (normative) Carbon Dioxide Emission Factor . 21
C.1 Determination of carbon dioxide emission factors . 21
C.2 Examples for carbon dioxide emission factors . 21
Bibliography . 24
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List of Figures
Figure 1 — Schematic relationship between the EN 50600 series of documents . 6
List of Tables
Table 1 — CUE Categories . 12
Table B.1 — Energy measurement methods at the data centre boundary . 20
Table C.1 — EFC examples by energy source . 21
Table C.2 — EFC examples for electricity from the grid by countries . 22
Table C.3 — EFC examples for refrigerants . 23
Table C.4 — Examples of GWP of GHG . 23

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EN 50600-4-8:2022 (E)
European foreword
This document (EN 50600-4-8:2022) has been prepared by CLC/TC 215 “Electrotechnical aspects of
telecommunication equipment”. It is based on the text of ISO/IEC 30134-8:2022 “Information technology - Data
centres key performance indicators - Part 8: Carbon usage effectiveness (CUE)”.
The following dates are fixed:
• latest date by which this document has to be (dop) 2023-12-12
implemented at national level by publication of
an identical national standard or by
endorsement
• latest date by which the national standards (dow) 2025-12-12
conflicting with this document have to be
withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights.
CENELEC shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a Standardizaton Request given to CENELEC by the European
Commission and the European Free Trade Association.
Any feedback and questions on this document should be directed to the users’ national committee. A complete
listing of these bodies can be found on the CENELEC website.

4

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SIST EN 50600-4-8:2023
EN 50600-4-8:2022 (E)
Introduction
The unrestricted access to internet-based information demanded by the information society has led to an
exponential growth of both internet traffic and the volume of stored/retrieved data. Data centres are housing and
supporting the information technology and network telecommunications equipment for data processing, data storage
and data transport. They are required both by network operators (delivering those services to customer premises)
and by enterprises within those customer premises.
Data centres usually provide modular, scalable and flexible facilities and infrastructures to easily accommodate the
rapidly changing requirements of the market. In addition, energy consumption of data centres has become critical
both from an environmental point of view (reduction of environmental footprint) and with respect to economical
considerations (cost of energy) for the data centre operator.
The implementation of data centres varies in terms of:
a) purpose (enterprise, co-location, co-hosting or network operator facilities);
b) security level;
c) physical size;
d) accommodation (mobile, temporary and permanent constructions).
The needs of data centres also vary in terms of availability of service, the provision of security and the objectives for
energy efficiency. These needs and objectives influence the design of data centres in terms of building construction,
power distribution, environmental control, telecommunications cabling and physical security as well as the operation
of the data centre. Effective management and operational information is important in order to monitor achievement of
the defined needs and objectives.
Recognizing the substantial resource consumption, particularly of energy, of larger data centres, it is also important
to provide tools for the assessment of that consumption both in terms of overall value and of source mix and to
provide Key Performance Indicators (KPIs) to evaluate trends and drive performance improvements.
At the time of publication of this document, the EN 50600 series is designed as a framework of standards, technical
specifications and technical reports covering the design, the operation and management, the key performance
indicators for energy efficient operation of the data centre as well as a data centre maturity model.
The EN 50600-2 series defines the requirements for the data centre design.
The EN 50600-3 series defines the requirements for the operation and the management of the data centre.
The EN 50600-4 series defines the key performance indicators for the data centre.
The CLC/TS 50600-5 series defines the data centre maturity model requirements and recommendations.
The CLC/TR 50600-99-X Technical Reports cover recommended practices and guidance for specific topics around
data centre operation and design.
This series of documents specifies requirements and recommendations to support the various parties involved in the
design, planning, procurement, integration, installation, operation and maintenance of facilities and infrastructures
within data centres. These parties include:
1) owners, operators, facility managers, ICT managers, project managers, main contractors;
2) consulting engineers, architects, building designers and builders, system and installation designers, auditors,
test and commissioning agents;
3) facility and infrastructure integrators, suppliers of equipment;
4) installers, maintainers.
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At the time of publication of this document, the EN 50600-4 series comprises the following documents:
EN 50600-4-1, Information technology — Data centre facilities and infrastructures — Part 4-1: Overview of and
general requirements for key performance indicators;
EN 50600-4-2, Information technology — Data centre facilities and infrastructures — Part 4-2: Power Usage
Effectiveness;
EN 50600-4-3, Information technology — Data centre facilities and infrastructures — Part 4-3: Renewable Energy
Factor;
EN 50600-4-6, Information technology — Data centre facilities and infrastructures — Part 4-6: Energy Reuse Factor;
EN 50600-4-7, Information technology — Data centre facilities and infrastructures — Part 4-7: Cooling Efficiency
Ratio;
EN 50600-4-8, Information technology — Data centre facilities and infrastructures — Part 4-8: Carbon Usage
Effectiveness;
EN 50600-4-9, Information technology — Data centre facilities and infrastructures — Part 4-9: Water Usage
Effectiveness
The inter-relationship of the documents within the EN 50600 series is shown in Figure 1.

Figure 1 — Schematic relationship between the EN 50600 series of documents
EN 50600-2-X documents specify requirements and recommendations for particular facilities and infrastructures to
support the relevant classification for “availability”, “physical security” and “energy efficiency enablement” selected
from EN 50600-1.
EN 50600-3-X documents specify requirements and recommendations for data centre operations, processes and
management.
EN 50600-4-X documents specify requirements and recommendations for key performance indicators (KPIs) used to
assess and improve the resource usage efficiency and effectiveness, respectively, of a data centre.
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NOTE Within the EN 50600-4-X series, the term “resource usage effectiveness” is more generally used for KPIs in
preference to “resource usage efficiency”, which is restricted to situations where the input and output parameters used to define
the KPI have the same units.
In today’s digital society data centre growth, and power consumption in particular, is an inevitable consequence and
that growth will demand increasing power consumption despite the most stringent energy efficiency strategies. This
makes the need for key performance indicators that cover the effective use of resources (including but not limited to
emissions essential.
energy) and the reduction of CO
2
In order to enable the optimum resource effectiveness of data centres a suite of effective KPIs is needed to measure
and report on resources consumed in order to develop an improvement roadmap.
These standards are intended to accelerate the provision of operational infrastructures with improved resource
usage effectiveness.
This document specifies the Carbon Usage Effectiveness (CUE), which provides a quantitative metric for the CO
2
intensity of the data centre
emissions attributed to a data centre. CUE is a simple method for reporting the CO
2
emissions, it is possible to present the data centre’s contribution to climate
during operation. By reporting CO
2
change (enhanced greenhouse effect).
This document is intended for use by data centre managers. Carbon Usage Effectiveness (CUE) will provide the
data centre manager quickly the sustainability of their data centres, compare the results, and determine if any
energy efficiency and/or sustainability improvements need to be made. The impact of operational carbon usage is
emerging as extremely important in the design, location, and operation of current and future data centres.
Additional standards in the EN 50600-4-X series will be developed, each describing a specific KPI for resource
usage effectiveness or efficiency.
The EN 50600-4-X series does not specify limits or targets for any KPI and does not describe or imply, unless
specifically stated, any form of aggregation of individual KPIs into a combined nor an overall KPI for data centre
resource usage effectiveness or efficiency.
This document is intended for use by and collaboration between data centre managers, facility managers, ICT
managers, and main contractors.
This series of European Standards does not address the selection of information technology and network
telecommunications equipment, software and associated configuration issues.
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EN 50600-4-8:2022 (E)
1 Scope
This document specifies the Carbon Usage Effectiveness as a KPI to quantify the CO emissions of a data centre
2
during the use phase of the data centre life cycle.
This document
a) defines the Carbon Usage Effectiveness (CUE) of a data centre,
b) introduces CUE measurement categories,
c) describes the relationship of this KPI to a data centre’s infrastructure, information technology equipment and
information technology operations,
d) defines the measurement, the calculation and the reporting of the parameter,
e) provides information on the correct interpretation of the CUE.
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.
EN 50600-4-1:2016, Information technology - Data centre facilities and infrastructures - Part 4-1: Overview of and
general requirements for key performance indicators
EN 50600-4-2, Information technology - Data centre facilities and infrastructures - Part 4-2: Power Usage
Effectiveness
ISO 8601-1, Date and time — Representations for information interchange — Part 1: Basic rules
3 Terms, definitions, abbreviations and symbols
3.1 Terms and definitions
For the purposes of this document the terms and definitions given in EN 50600-4-1, EN 50600-4-2 and the following
apply.
ISO and IEC maintain terminological 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
Carbon Usage Effectiveness
emissions and IT equipment energy demand
ratio of the data centre annual CO
2
3.1.2
total data centre energy consumption
total annual energy consumption for all energy types serving the data centre at its boundary
Note 1 to entry: The total data centre energy is measured in kWh; the energy is measured with energy metering devices at the
boundary of the data centre or points of generation within the boundary.
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Note 2 to entry: This includes energy derived from sources such as natural gas, hydrogen, bioethanol and district utilities (e.g.
chilled water, condenser water).
Note 3 to entry: Total annual energy includes supporting infrastructure.
3.1.3
IT equipment energy consumption
energy consumed by equipment that is used to manage, process, store or route data within the computer room
space
Note 1 to entry: The IT equipment energy consumption is measured in kWh; examples for IT equipment are servers, storage
equipment, and telecommunications equipment.
Note 2 to entry: IT equipment energy use follows same categories as in EN 50600-4-2.
3.1.4
global warming potential
radiative impact of a given greenhouse gas relative to that of carbon dioxide
3.1.5
greenhouse gases
gaseous constituent of the atmosphere that absorbs and emits radiation at specific wavelengths within the spectrum
of infrared radiation emitted by the earth's surface, the atmosphere, and clouds
Note 1 to entry: For the purposes of this document seven GHG are considered: carbon dioxide (CO ), methane (CH ), nitrous
2 4
oxide (N O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulphur hexafluoride (SF ) and Nitrogen trifluoride (NF ).
2 6 3
Note 2 to entry: A list of greenhouse gases with their recognized global warming potentials is provided in EN ISO 14067.
3.1.6
carbon dioxide equivalent
global warming potential of a greenhouse gas expressed in terms of the global warming potential of one unit of
carbon dioxide
3.1.7
carbon dioxide emission factor
specific carbon dioxide emission stemming from the data centre’s energy use and facility operations
Note 1 to entry: The term “facility operations” covers CO emissions caused e.g. by refrigerants or diesel generators.
2
3.2 Abbreviations
For the purposes of this document, the abbreviations of EN 50600-4-1 and the following apply.
CUE Carbon Usage Effectiveness
CO carbon dioxide
2
CO e carbon dioxide equivalent
2
DC data centre
DC CO data centre related carbon dioxide emissions
2
EFC Carbon Dioxide Emission Factor
GHG Greenhouse Gases
PUE Power Usage Effectiveness
pCUE partial carbon usage effectiveness
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EN 50600-4-8:2022 (E)
dCUE design carbon usage effectiveness
iCUE interim carbon usage effectiveness
3.3 Symbols
For the purposes of this document the following symbols apply.
CA filling capacity of refrigerant
rf
C EFC in kg CO e/kWh
f 2
C EFC of external energy demand in kg CO e/kWh
f,ex 2
C EFC of external electrical energy demand from the grid
f,ex,el
C EFC of internal energy demand in kg CO e/kWh
f,int 2
C EFC of internal electrical energy demand
f,int,el
C EFC of refrigerant
f,int,rf
DC CO emissions of the data centre in kg
CO2 2
DC DC CO emissions of electricity from the grid in kg
CO2,ex,el 2
DC DC CO fugitive emissions in kg
CO2,fg 2
DC DC CO emissions of on-site electricity generation in kg
CO2,int,el 2
E total data centre energy consumption (annual) in kWh
DC
E IT equipment energy consumption (annual) in kWh
IT
E acquired electrical energy from outside the data centre boundaries in kWh
ex
E electrical energy produced inside the data centre boundaries in kWh
in
lk annual leakage rate
a
lk monthly leakage rate
m
P annual average data centre power in kW
DC
rt runtime of diesel engines
D
S CO emissions of a subsystem in kg
CO2 2
4 Applicable area of the data centre
Carbon Usage Effectiveness as specified in this document:
a) is associated with the data centre infrastructure and IT equipment within its boundaries only;
b) describes the Carbon Usage Effectiveness relative to facilities with given environmental conditions, IT load
characteristics, availability requirements, maintenance, and security requirement;
c) measures the relationship between the total data centre CO emissions and the IT equipment energy
2
consumed.
CUE does not:
1) account for the efficiency of other resources such as human resource, space or water;
2) provide a data centre productivity metric;
3) provide a standalone, comprehensive efficiency metric.
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5 Determination of Carbon Usage Effectiveness
CUE provides a way to determine the carbon emissions associated with data centres. CUE will range from 0 to
infinity. CUE has an ideal value of 0,0, indicating that no carbon use is associated with the data centre’s operations.
CUE has no theoretical upper boundary.
Carbon Usage Effectiveness (CUE) is defined as:
CUE = DC /E (1)
CO2 IT
where
DC is the CO emissions of the data centre in kg;
CO2 2
E is the IT equipment energy consumption (annual) in kWh.
IT
NOTE 1 The values for DC differ regarding to the CUE category (see 6.2.2).
CO2
NOTE 2 The accuracy of measuring IT energy for CUE is not necessarily the same as the accuracy of measuring IT energy
for PUE (e.g. CUE category 1 can be reported with an accuracy of measuring IT energy referring to PUE category 2).
CUE may be applied in mixed use buildings when measurement of the CO emissions caused by the data centre
2
and that for other functions is possible.
6 Measurement of Carbon Usage Effectiveness
6.1 General
All Key Performance Indicators of the EN 50600-4 series are defined within the same boundaries.
6.2 Calculation and measurement method of CO
2
6.2.1 Calculation and measurement period and frequency
The calculation of CUE requires the recording and documenting of DC CO values and E over a coincident period
2 IT
of 12 months. This document does not specify the frequency of measurements of DC CO -related emission sources
2
and E , since CUE is calculated on an annual timeframe. However, the frequency of measurement employed will
IT
determine the timing of subsequent CUE calculations on a rolling annual basis. The required EFC values shall be
determined in accordance with Annex C.
NOTE 1 The frequency of measurements or assessments can be useful for the improvement of sub-systems, but is not
required for CUE disclosure.
NOTE 2 There are some direct measurements for CO (e.g. for diesel engines). But there are also calculations by
2
measurement of energy, refrigerant losses, etc. and their EFC.
6.2.2 Categories of Carbon Usage Effectiveness
6.2.2.1 General
Category 1 and category 2 (see Table 1) differ with respect to the sources of CO emissions considered. Category 2
2
is more comprehensive than Category 1, as it considers more emission sources.
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Table 1 — CUE Categories
 Category 1 (CUE ) Category 2 (CUE ) Category 3 (CUE )
1 2 3
basic intermediate advanced
Considered external and internal external and internal reserved for future
emission data centre electricity data centre electricity, use
source all additional data
centre energy supply
and all additional data
centre emission
sources
Considered CO CO equivalents reserved for future
2 2
greenhouse use
gases
6.2.2.2 CUE category 1: CO emissions from electricity
2
For category 1 CO emissions of all internal and external power supply are considered. For category 1 only
2
electricity is considered. For instance internal power supply can come from diesel engines and external power
supply can come from acquired electricity from the grid. In case that different energy sources are used, Annex B
provides examples for energy conversion factors.
The CUE of category 1 only covers CO as one of the GHGs.
2
For category 1 CUE can be calculated according to Formula (2).
DC
(E × C )+ (E × C )
CO
ex, el f, ex, el int, el f, int, el
2
CUE (2)
1
EE
IT IT
where
E is the electrical energy acquired from outside the data centre boundaries (annual);
ex,el
E is the electrical energy produced inside the data centre boundaries (annual);
int,el
C is the EFC of external electrical energy demand;
f,ex,el
C is the EFC of internal electrical energy demand;
f,int,el
E is the IT equipment energy consumption (annual) in kWh.
IT
In the case of different electricity generation sources with different C values, this shall be reflected in the application
f
of Formula (2) accordingly.
6.2.2.3 CUE category 2: CO emissions from entire energy
2
The CUE of category 2 covers both CO emissions and CO e for all external and internal power supply, for all
2 2
additional energy supply and for all additional CO e
...

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