CEN/TC 371 N 260. N260 - EPBD Overarching Standard for dispatch of ENQ draft to CMC. Document type: Other meeting document

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CEN/TC 371

CEN/TC 371 - Project Committee - Energy Performance of Building project group Email of secretary: [email protected]

Secretariat: NEN (Netherlands)

N260 - EPBD Overarching Standard for dispatch of ENQ draft to CMC

Document type: Other meeting document

Date of document: 2012-12-21

Expected action: MEET

Background:

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Document type: European Standard Document subtype:

Document stage: CEN Enquiry

Date: 2012-10

prEN O.A.:2012

CEN/TC 371

Secretariat: NEN

Energy performance of buildings — Overarching standard EPBD

Einführendes Element — Haupt-Element — Ergänzendes Element

Élément introductif — Élément central — Élément complémentaire

ICS:

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C.5.1 General ... 83 C.5.2 Sub-division rule. ... 84 C.5.3 Distribution rule ... 84 C.6 Ventilation zones ... 84 C.6.1 General ... 84 C.6.2 Sub-division rule ... 84 C.6.3 Distribution rule ... 84 C.7 Humidification/dehumidification ... 84

(informative) Alphabetical index of terms ... 85

Annex D D.1 Alphabetical list of terms defined ... 85

D.2 List of English, French and German terms used for symbols ... 88

D.3 List of English, French and German terms used for subscripts ... 89

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Foreword

This document (prEN 15603 OA:2012) has been prepared by Technical Committee CEN/TC 371 “Energy Performance of Buildings Project Group”, the secretariat of which is held by NEN.

This document is currently submitted to the CEN Enquiry.

This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s).

This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association (Mandate M/480, [2]), and supports essential requirements of EU Directive 2010/31/EC on the energy performance of buildings (EPBD). It forms part of a series of standards aimed at European harmonisation of the methodology for the calculation of the energy performance of buildings.

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Introduction

Energy assessments of buildings are carried out for various purposes, such as:

a) judging compliance with building regulations expressed in terms of a limitation on energy use or a related quantity;

b) increasing transparency in commercial operations through the energy certification and/or display of a level of energy

c) monitoring of the energy efficiency of the building and its technical building systems;

d) helping in planning retrofit measures, through prediction of energy savings which would result from various actions.

This standard specifies a general framework for the assessment of overall energy use of a building, and the calculation of energy ratings in terms of primary energy or other energy related metrics. Separate standards provide methodologies that may be uses to calculate the energy use of services within a building (heating, cooling, hot water, ventilation and lighting) and produce results that are used here in combination to show overall energy use.

This assessment is not limited to the building alone, but takes into account the wider environmental impact of the energy supply chain.

This standard replaces EN 15603:2008 and parts of other EN or EN-ISO standards published in 2007-2008 under the mandate M/343 on the EPBD. This revision was required as a result of the EPBD recast (2010/31/EU).The set of standards developed under mandate M/343 will be revised to become consistent with this overarching standard under mandate M/480. For many of these standards the revisions are mainly editorial plus changes to make the procedures unambiguous and software proof and to rationalize the choices.

More information is provided in the Technical Report accompanying this standard (EN TR OA, under preparation).

To provide flexibility to the EU Member States in the application of the set of CEN standards, clearly identified options are given, with a rational for the choices.

In order to progress on harmonization, reproducibility and transparency default CEN options are provided at relevant positions in the standards.

At national level these default CEN options may be replaced by a National Annex, following the models provided in the relevant standards.

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1 Scope

This standard provides a systematic, comprehensive and modular overall structure on the integrated energy performance of buildings, in order to ensure consistency among all CEN standards required to calculate the energy performance of buildings according to the EPBD (2010/31/EU).

This standard handles the framework of the overall energy performance of a building, covering inter alia:

a) common terms, definitions and symbols;

b) building and system boundaries;

c) building partitioning;

d) methodology for calculating the energy performance of a building (set of overall equations on energy used, delivered, produced and/or exported at the building site and near-by);

e) set of overall equations and input-output relations, linking the various elements relevant for the assessment of the overall energy performance of buildings which are treated in separate standards;

f) general requirements to standards dealing with partial calculations;

g) general rules in setting out alternative calculation routes according to the calculation scope and requirements;

h) rules for the combination of different partitioning;

i) performance indicators;

j) methodology for measured energy performance assessment.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

CEN/TS BP, Energy Performance of Buildings – Basic principles for the set of EPBD standards (in preparation)

CEN/TS DTR, Energy Performance of Buildings – Detailed technical rules for the set of EPBD standards (in preparation)

EN ISO 7345:1995, Thermal insulation – Physical quantities and definitions ISO 13600:1997, Technical energy systems – Basic concepts

EN ISO 13790, Energy performance of buildings – Calculation of energy use for space heating and cooling EN 15241, Ventilation for buildings – Calculation methods for energy losses due to ventilation and infiltration in commercial buildings

EN 15243, Ventilation for buildings – Calculation of room temperatures and of load and energy for buildings with room conditioning systems

EN 15316, Heating systems in buildings – Method for calculation of system energy requirements and system efficiencies

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3 Terms and definitions

For the purposes of this European Standard, the terms and definitions given in EN ISO 7345:1995 and the following apply.

Given the scope of this over-arching standard, these definitions are applicable to all standards that are necessary to assess the energy performance of buildings.

NOTE 1 The terms and definitions are adopted from CEN TR 15615:2008 and correspond with the terms and definitions in EN 15603:2008.

NOTE 2 An alphabetic list of all terms defined in this clause is given in D.

3.1 Buildings

3.1.1 building

construction as a whole, including its envelope and all technical building systems, for which energy is used to condition the indoor climate, to provide domestic hot water and illumination and other services related to the use of the building

NOTE The term can refer to the building as a whole or to parts thereof that have been designed or altered to be used separately.

3.1.2

building automation and control

products, software, and engineering services for automatic controls, monitoring and optimization, human intervention, and management to achieve energy-efficient, economical, and safe operation of building services equipment

3.1.3

building category

classification of buildings and/or building units and/or building spaces related to the use

3.1.4

building element

technical building system or an element of the building envelope

3.1.5

building services

services provided by technical building systems and by appliances to provide acceptable indoor climate conditions, domestic hot water, illumination levels and other services related to the use of the building

3.1.6

building unit

section, floor or apartment within a building which is designed or altered to be used separately

3.1.7

conditioned area

floor area of conditioned spaces excluding non-habitable cellars or non-habitable parts of a space, including the floor area on all storeys if more than one

NOTE 1 Internal, overall internal or external dimensions can be used. This leads to different areas for the same building.

NOTE 2 Some services, such as lighting or ventilation, might be provided to areas not included in this definition (e.g. a car park).

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NOTE 4 Conditioned area can be taken as the useful area mentioned in the Articles 5, 6 and 7 of the EPBD1) unless it is otherwise defined in national regulations.

3.1.8

conditioned space

ventilated and/or, heated and/or cooled and/or lighted space for human occupancy

NOTE The heated and/or cooled spaces are used to define the thermal envelope. 3.1.9

conditioned zone

part of a conditioned space with a given set-point temperature or set-point temperatures, throughout which there is the same occupancy pattern and the internal temperature which is controlled by a single heating system, cooling system and/or ventilation system

3.1.10

cooled space

room or enclosure which for the purposes of a calculation is assumed to be cooled to a given set-point temperature or set point temperatures

3.1.11

dehumidification

process of removing water vapour from air

3.1.12

domestic hot water heating

process of heat supply to raise the temperature of the cold water to the intended delivery temperature

3.1.13

existing building

for calculated energy rating: building that is erected

for measured energy rating: building for which actual data necessary to assess the energy use are known or can be measured

3.1.14

external dimension

dimension measured on the exterior of a building

3.1.15

heated space

room or enclosure which for the purposes of a calculation is assumed to be heated to a given set-point temperature or set point temperatures

3.1.16

humidification

process of adding water vapour to air to increase humidity

3.1.17

internal dimension

dimension measured from wall to wall and floor to ceiling inside a room of a building

3.1.18 lighting

process of supplying illumination

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3.1.19 new building

for calculated energy rating: building at design stage or under construction

for measured energy rating: building recently constructed without reliable records of energy use

3.1.20

occupied zone

part of a conditioned zone in which persons normally reside and where requirements as to the indoor environment are to be satisfied

NOTE The definition of the occupied zone depends on the geometry and the use of the room and is specified case by case. Usually the term “occupied zone” is used only for areas designed for human occupancy and is defined as a volume of air that is confined by specified horizontal and vertical planes. The vertical planes are usually parallel with the walls of the room. Usually there is also a limit placed on the height of the occupied zone.

3.1.21

other services

services supplied by energy consuming appliances

3.1.22

overall internal dimension

dimension measured on the interior of a building, ignoring internal partitions

3.1.23

space cooling

process of heat extraction for thermal comfort

3.1.24

space heating

process of heat supply for thermal comfort

3.1.25

technical building sub-system

part of a technical building system that performs a specific function (e.g. heat generation, heat distribution, heat emission)

3.1.26

technical building system

technical equipment for heating, cooling, ventilation, domestic hot water, lighting and electricity production

NOTE 1 A technical building system can refer to one or to several building services (e.g. heating system, heating and DHW system).

NOTE 2 A technical building system is composed of different subsystems. NOTE 3 Electricity production can include cogeneration and photovoltaic systems. 3.1.27

thermal envelope area

total of the area of all elements of a building that enclose conditioned spaces through which thermal energy is transferred to or from the external environment or to or from unconditioned spaces

NOTE 1 Thermal element area depends on whether internal, overall internal or external dimensions are being used. NOTE 2 The respective areas of the building envelope may be weighted with a (nationally fixed) reduction factor in

case of e.g. unheated adjacent spaces and ground floors. 3.1.28

unconditioned space

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3.1.29 ventilation

process of supplying or removing air by natural or mechanical means to or from a space

NOTE Such air is not required to have been conditioned.

3.2 Technical building systems

3.2.1

air conditioning system

combination of all components required to provide a form of air treatment in which temperature is controlled, possibly in combination with the control of ventilation, humidity and air cleanliness

3.2.2

auxiliary energy

electrical energy used by technical building systems for heating, cooling, ventilation, lighting and/or domestic water to support energy transformation to satisfy energy needs

NOTE 1 This includes energy for fans, pumps, electronics, etc. Electrical energy input to the a ventilation system for air transport and heat recovery is not considered as auxiliary energy, but as energy use for ventilation NOTE 2 In EN ISO 9488, Solar energy – Vocabulary, the energy used for pumps and valves is called "parasitic

energy". 3.2.3

cogeneration

simultaneous generation in one process of thermal energy and electrical or mechanical energy

NOTE Also known as combined heat and power (CHP). 3.2.4

demand controlled ventilation

ventilation system in which the room airflow rate is governed by an automatic control depending on occupancy and an indoor air quality indicator (CO2, H2O, or pollutant)

3.2.5

heat recovery

heat generated by a technical building system or linked to a building use (e.g. domestic hot water) which is utilised directly in a related system to lower the heat input and which would otherwise be wasted (e.g. preheating of the combustion air by a flue gas heat exchanger)

3.2.6

part load operation

operational state of a technical system (e.g. heat pump), where the actual load is below the actual output capacity of the device

3.2.7

recoverable system thermal loss

part of a system thermal loss which can be recovered to lower either the energy need for heating or cooling or the energy use of the heating or cooling system

NOTE This depends on the calculation approach chosen to calculate the recovered gains and losses (holistic or simplified approach).

3.2.8

recovered system thermal loss

part of the recoverable system thermal loss which has been recovered to lower either the energy need for heating or cooling or the energy use of the heating or cooling system

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3.2.9

room conditioning system

system capable of maintaining comfort conditions in a room within a defined range.

NOTE Such systems comprise air conditioning and surface based radiative systems. 3.2.10

system thermal loss

thermal loss from a technical building system for heating, cooling, domestic hot water, humidification, dehumidification or ventilation that does not contribute to the useful output of the system

NOTE 1 A system loss can become an internal heat gain for the building if it is recoverable

NOTE 2 Thermal energy recovered directly in the subsystem is not considered as a system thermal loss but as heat recovery and directly treated in the related system standard.

NOTE 3 Heat dissipated by the lighting system or by other services (e.g. appliances of computer equipment) is not part of the system thermal losses, but part of the internal heat gains.

3.2.11

ventilation heat recovery

heat recovered from the exhaust air to reduce the ventilation heat transfer

3.3 Inspection of technical building systems

3.3.1

commissioning

sequence of events to enable the functioning of a building and its heating, ventilation, room conditioning (HVAC) system and lighting in accordance with the design parameters

3.3.2

design criteria

set of descriptions based on a particular environmental element such as indoor air quality, satisfactory lighting, thermal and acoustical comfort, energy efficiency and associated system controls to be used for assessing plant operation

3.3.3

design documentation

written description of the essential design elements of a plant

3.3.4

energy inspection

examination of heating, room conditioning systems and/or lighting in a building

3.3.5 inspector

person having appropriate training or practical experience in energy inspection of heating, room conditioning systems and/or lighting and associated regulations for energy

3.3.6

room conditioning system control

measures taken to enable operation of a system in accordance with the design criteria

NOTE It can be a part of the building automation and control system.

3.4 Energy

3.4.1

assessment boundary

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3.4.2

building site “on site”

building and the premises on which the building is located

3.4.3

CO2 emission coefficient

given energy carrier, quantity of CO2 emitted to the atmosphere per unit of delivered energy

NOTE The CO2 emission coefficient can also include the equivalent emissions of other greenhouse gases (e.g.

methane). 3.4.4

delivered energy

energy, expressed per energy carrier, supplied to the technical building systems through the system boundary, to satisfy the uses taken into account (heating, cooling, ventilation, domestic hot water, lighting, appliances etc.) or to produce electricity

NOTE 1 For active solar and wind energy systems the incident solar radiation on solar panels or on solar collectors or the kinetic energy of wind is not part of the energy balance of the building. It is decided at national level whether or not renewable energy produced on site is part of the delivered energy.

NOTE 2 Delivered energy can be calculated for defined energy uses or it can be measured.

NOTE 3 Lighting fitted to the outside of the building envelope is not part of the EP uses (assessment). 3.4.5

distant to the building site

outside the assessment boundaries and outside the building site

NOTE Energy sources which are not distributed through a specific network to the assessed building or building unit and which are not designed for a particular building site.

3.4.6

electricity grid

public electricity network

3.4.7

energy carrier

substance or phenomenon that can be used to produce mechanical work or heat or to operate chemical or physical processes [ISO 13600:1997]

NOTE 1 The energy content of fuels is given by their gross calorific value.

NOTE 2 The energy need can include additional heat transfer resulting from non-uniform temperature distribution and non-ideal temperature control, if they are taken into account by increasing (decreasing) the effective temperature for heating (cooling) and not included in the heat transfer due to the heating (cooling) system. 3.4.8

energy need for domestic hot water

heat to be delivered to the needed amount of domestic hot water to raise its temperature from the cold network temperature to the prefixed delivery temperature at the delivery point

3.4.9

energy need for heating or cooling

heat to be delivered to or extracted from a conditioned space to maintain the intended temperature conditions during a given period of time

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3.4.10

energy need for humidification or dehumidification

latent heat in the water vapour to be delivered to or extracted from a conditioned space by a technical building system to maintain a specified minimum or maximum humidity within the space

3.4.11

energy source

source from which useful energy can be extracted or recovered either directly or by means of a conversion or transformation process

NOTE Examples include oil or gas fields, coal mines, sun, forests etc. 3.4.12

energy use for lighting

electrical energy input to a lighting system

3.4.13

energy use for other services

electrical energy input to appliances providing other services

NOTE This refers to services other than heating, cooling, domestic hot water, ventilation and lighting. 3.4.14

energy use for space heating or cooling or domestic hot water

energy input to the heating, cooling or hot water system to satisfy the energy need for heating, cooling (including dehumidification) or hot water respectively

NOTE If the technical building system serves several purposes (e.g. heating and domestic hot water) it can be difficult to split the energy use into that used for each purpose. It can be indicated as a combined quantity (e.g. energy need for space heating and domestic hot water).

3.4.15

energy use for ventilation

electric energy input to a ventilation system for air transport and heat recovery (not including energy input for preheating the air) and energy input to the humidification systems to satisfy the need for humidification

3.4.16

exported energy

energy, expressed per energy carrier, delivered by the technical building systems through the system boundary and used outside the system boundary

NOTE 1 It can be specified by generation types (e.g. CHP, photovoltaic, etc) in order to apply different weighting factors.

NOTE 2 Exported energy can be calculated or it can be measured. 3.4.17

gross calorific value

quantity of heat released by a unit quantity of fuel, when it is burned completely with oxygen at a constant pressure equal to 101 320 Pa, and when the products of combustion are returned to ambient temperature

NOTE 1 This quantity includes the latent heat of condensation of any water vapour contained in the fuel and of the water vapour formed by the combustion of any hydrogen contained in the fuel.

NOTE 2 According to ISO 13602-2, the gross calorific value is preferred to the net calorific value. NOTE 3 The net calorific value does not take account of the latent heat.

3.4.18

nearby the building site

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NOTE Thermal energy, or electricity which is distributed through a specific network. 3.4.19

net delivered energy

delivered energy minus exported energy, both expressed per energy carrier

NOTE 1 A balance of the delivered and exported energy per energy carrier can be performed only if the same primary energy factors and/or CO2 coefficients apply to the delivered and exported amounts of that energy

carrier.

NOTE 2 The term "net" can also be applied to quantities derived from net delivered energy, e.g. primary energy or CO2 emissions.

3.4.20

non-renewable energy

energy taken from a source which is depleted by extraction (e.g. fossil fuels)

3.4.21

non-renewable primary energy factor

for a given energy carrier, renewable primary energy divided by delivered energy, where the renewable energy is that required to supply one unit of delivered energy, taking account of the non-renewable energy required for extraction, processing, storage, transport, generation, transformation, transmission, distribution, and any other operations necessary for delivery to the building in which the delivered energy will be used

NOTE The non-renewable primary energy factor can be less than unity if renewable energy has been used. 3.4.22

primary energy

energy that has not been subjected to any conversion or transformation process

NOTE 1 Primary energy includes non-renewable energy and renewable energy. If both are taken into account it can be called total primary energy.

NOTE 2 For a building, it is the energy used to produce the energy delivered to the building. It is calculated from the delivered and exported amounts of energy carriers, using conversion factors.

3.4.23

renewable energy

energy from a source that is not depleted by extraction, such as solar energy (thermal and photovoltaic), wind, water power, renewed biomass

NOTE In ISO 13602-1:2002, renewable resource is defined as "natural resource for which the ratio of the creation of the natural resource to the output of that resource from nature to the techno-sphere is equal to or greater than one".

3.4.24

renewable energy produced on the building site

energy produced by technical building systems directly connected to the building using renewable energy sources

3.4.25

total primary energy factor

for a given energy carrier, non-renewable and renewable primary energy divided by delivered energy, where the primary energy is that required to supply one unit of delivered energy, taking account of the energy required for extraction, processing, storage, transport, generation, transformation, transmission, distribution, and any other operations necessary for delivery to the building in which the delivered energy will be used

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3.5 Energy ratings and certification

3.5.1

calculated energy rating

energy rating based on calculations of the weighted net delivered energy used by a building for heating, cooling, ventilation, domestic hot water and lighting

NOTE National bodies can decide whether other energy uses resulting from occupants' activities such as cooking, production, laundry, computer equipment, etc. are included or not. If included, standard input data needs to be provided for the various types of building and uses. Lighting is always included except (by decision of national bodies) for residential buildings.

3.5.2

confidence interval

interval that has a high probability (e.g. 95 %) to include the actual value

3.5.3

design energy rating

energy rating with design data for the building and standard use data set

NOTE It represents the calculated intrinsic annual energy use of a designed building under standardised conditions. This is particularly relevant to obtain a building permit at the design stage.

3.5.4

energy certificate

certificate recognised by a Member State or by a legal person designated by it, which indicates the energy performance of a building or building unit, calculated according to a methodology adopted in accordance with Article 3 of DIRECTIVE 2010/31/EU

NOTE The meaning of the terms “certificate” and "certification" in this standard differ from that in EN ISO/IEC 17000, Conformity assessment – Vocabulary and general principles (ISO/IEC 17000:2004).

3.5.5

energy certification

procedures enabling production of an energy certificate

3.5.6

energy class

easy to understand metric (e.g. A to G) for indicating the energy performance of a building

3.5.7

energy performance indicator

energy rating divided by conditioned area

3.5.8

energy performance of a building

calculated or measured amount of weighted net delivered energy actually used or estimated to meet different needs associated with a standardised use of a building, which may include, inter alia, energy used for heating, cooling, ventilation, domestic hot water and lighting

3.5.9

energy performance requirement

minimum level of energy performance that is to be achieved to obtain a right or an advantage: e.g. right to build, lower interest rate, quality label

3.5.10

energy rating

evaluation of the energy performance of a building based on the weighted sum of the calculated or measured use of energy carriers

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3.5.11

measured energy indicator

measured energy rating divided by conditioned area

3.5.12

measured energy rating

energy rating based on measured amounts of delivered and exported energy

NOTE 1 The measured rating is the weighted sum of all energy carriers used by the building, as measured by meters or other means. It is a measure of the in-use performance of the building. This is particularly relevant to certification of actual energy performance.

NOTE 2 Also known as "operational rating". 3.5.13

reference value

standard legal or calculated value against which an energy indicator is compared

3.5.14

standard energy indicator

standard energy rating divided by conditioned area

3.5.15

standard energy rating

calculated energy rating using actual data for a building and a standard use data set

NOTE 1 It represents the intrinsic annual energy use of a building under standardised conditions. This is particularly relevant to certification of standard energy performance.

NOTE 2 It can also be termed "asset energy rating". 3.5.16

standard use data set

standard input data for internal and external climates, use, and occupancy

NOTE 1 This set can also include information on surroundings (such as shading or sheltering by adjacent buildings).

NOTE 2 Such data sets are defined at national level. 3.5.17

statistical tolerance interval

interval determined from a random sample in such a way that one may have a specified level of confidence that the interval covers at least a specified proportion of the sampled population

NOTE The confidence level in this context is the long-run proportion of intervals constructed in this manner that will include at least the specified proportion of the sampled population.

3.5.18

tailored energy rating

calculated energy rating using actual data for a building and actual climate and occupancy data

3.6 Costs

3.6.1

reasonable cost

cost that is accepted by all parties to reach a given purpose

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NOTE 2 This cost strongly depends on the purpose of the effort. For example, the cost of a rating could be relatively large if it is to provide an official certificate to put the building on the market or for displaying the building performance to the public, but reduced if it is simply for statistical purpose.

3.6.2

reasonably possible

can be achieved at a reasonable cost

3.7 Energy calculation

3.7.1

building calculation model

mathematical model of the building, used to calculate its energy use

3.7.2

building heat transfer coefficient

sum of transmission and ventilation heat transfer coefficients

3.7.3

calculation period

period of time over which the calculation is performed

NOTE The calculation period can be divided into a number of calculation steps. 3.7.4

calculation step

discrete time interval for the calculation of the energy needs and uses for heating, cooling, ventilation, lighting, humidification and dehumidification

NOTE Possible discrete time intervals are one hour, one month, one heating and/or cooling season, one year, operating modes, and bins.

3.7.5

equivalent internal temperature

constant minimum internal temperature, assumed for the calculation of the energy for heating, or maximum internal temperature, assumed for the calculation of the energy for cooling, leading approximately to the same average heat transfer as would apply with intermittent heating or cooling, and with inaccuracy of room temperature control

3.7.6

external temperature temperature of external air

NOTE 1 For transmission heat transfer calculations, the radiant temperature of the external environment is supposed equal to the external air temperature; long-wave transmission to the sky is calculated separately. NOTE 2 The measurement of external air temperature is defined in EN ISO 15927-1, Hygrothermal performance of buildings – Calculation and presentation of climatic data – Part 1: Monthly means of single meteorological elements (ISO 15927-1)

3.7.7

gain utilisation factor

factor reducing the total monthly or seasonal heat gains to obtain the resulting reduction of the energy need for heating

3.7.8

heat balance ratio

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3.7.9 heat gains

heat generated within or entering into the conditioned space from heat sources other than energy intentionally utilised for heating, cooling or domestic hot water preparation

NOTE 1 These include internal heat gains and solar heat gains. Sinks that extract heat from the building, are included as gains, with a negative sign. In contrast with heat transfer, for a heat source (or sink) the difference between the temperature of the considered space and the temperature of the source is not the driving force for the heat flow.

NOTE 2 For summer conditions heat gains with a positive sign constitute extra heat load on the space. 3.7.10

heating or cooling season

period of the year during which a significant amount of energy for heating or cooling is needed

NOTE The season lengths are used to determine the operation period of technical systems. 3.7.11

heat transfer coefficient

heat flow rate divided by temperature difference between two environments; specifically used for heat transfer coefficient by transmission or ventilation

3.7.12

intermittent heating or cooling

heating or cooling pattern where normal heating or cooling periods alternate with periods of reduced or no heating or cooling

3.7.13

internal heat gains

heat provided within the building by occupants (sensible metabolic heat) and by appliances such as lighting, domestic appliances, office equipment, etc., other than energy intentionally provided for heating, cooling or hot water preparation

NOTE This includes recoverable system thermal losses, if the holistic approach for the calculation of the recovered system losses is chosen.

3.7.14

internal temperature

arithmetic average of the air temperature and the mean radiant temperature at the centre of the occupied zone

NOTE This is the approximate operative temperature according to EN ISO 7726, Ergonomics of the thermal environment – Instruments for measuring physical quantities (ISO 7727:1998).

3.7.15

loss utilisation factor

factor reducing the total monthly heat transfer to obtain the resulting reduction of the energy need for cooling

3.7.16

set-back temperature

minimum internal temperature to be maintained during reduced heating periods, or maximum internal temperature to be maintained during reduced cooling periods

3.7.17

set-point temperature of a conditioned zone

internal (minimum intended) temperature, as fixed by the control system in normal heating mode, or internal (maximum intended) temperature, as fixed by the control system in normal cooling mode

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3.7.18

solar heat gain

heat provided by solar radiation entering, directly or indirectly (after absorption in building elements), into the building through windows, opaque walls and roofs, or passive solar devices such as sunspaces, transparent insulation and solar walls

NOTE Active solar devices such as solar collectors are considered as part of the technical building system. 3.7.19

solar irradiation

incident solar heat per area over a given period

3.7.20

transmission heat transfer coefficient

heat flow rate due to thermal transmission through the fabric of a building, divided by the difference between the environment temperatures on either side of the construction

NOTE By convention, if the heat is transferred between a conditioned space and the external environment, the sign is positive if the heat flow is from the space to outside (heat loss).

3.7.21

useful heat gains

proportion of internal and solar heat gains that contribute to reducing the energy need for heating

3.7.22

validated building data set

data used as input to a building calculation model in which one or more input data have been adjusted on the basis of actual data so that the results from a calculation using the model do not significantly differ from the measured reality

NOTE The quality of the validated data set is a balance between reasonable costs for gathering data and reasonable accuracy.

3.7.23

ventilation heat transfer coefficient

heat flow rate due to air entering a conditioned space either by infiltration or ventilation, divided by the difference between the internal air temperature and the supply air temperature

4 Symbols, units, subscripts and abbreviations

NOTE 1 The symbols, units and subscripts and the rules for application are adopted from CEN/TR 15615:2008 and correspond with the symbols, units and subscripts in EN 15603:2008.

NOTE 2 The set of EPBD standards introduces a large number of quantities and their associated symbols. To facilitate the use of these standards, a common set of symbols and subscripts have been defined, as given in Table 1 and Table 2. The symbols follow established standards on nomenclature such as EN ISO 7345 and introduce others that are common to the set of EPBD standards; in particular a set of subscripts to distinguish between different energy uses, different energy carriers, etc.

The symbols given in Table 1 concern only data passed from one standard to another. Additional symbols and units may be used locally within each standard, but it is strongly recommended to use the common symbols, subscripts and order.

Tables 1 and 2 provide the main symbols and subscripts. Annex B (normative) provides a more rules for application (hierarchy) of subscripts.

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Table 1 —Symbols and units

Symbol Quantity Unit

A area m²

b temperature reduction factor -

C heat capacity J/K a)

c specific heat capacity J/(kg•K) a)

c coefficient d) _various

d thickness m

D diameter m

E energy in general e) kg, m3, (kW•h), J

a) b)

EP energy performance indicator J/(m2•a),

kg/(m2•a), €/(m2_•a)_{a) c)}

f factor (e.g. primary energy factor, policy factor, …) – d)

H heat transfer coefficient W/K

H calorific value MJ/kg

h surface coefficient of heat transfer W/(m²•K)

I solar irradiance W/m2

k coefficient d)

K CO2 emission coefficient kg/J; g/(kW•h)

L length m

m mass (e.g. quantity of CO2 emissions) kg

n air exchange rate 1/h

N number of items (integer only) –

O occupancy persons

p pressure Pa

P power in general including electrical power W

Q quantity of heat J, (kW•h) a)

q volumetric airflow rate m3/s

q heat flow density W/m²

R thermal resistance m²·K/W

RER renewable energy ratio –

T thermodynamic temperature K

t time, period of time s a)

U thermal transmittance W/(m²•K)

V volume m³

W (electrical) auxiliary energy (kW•h), J a)

x relative humidity %

X volume fraction %

X, Y any property, system, … –

Δ delta (difference) prefix to be combined with symbols various

 efficiency factor -

ϑ Celsius temperature °C

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Table 1 (end)

 linear thermal transmittance W/(m•K)

 heat flow rate, thermal power W

 point thermal transmittance W/K

 density kg/m³

 time constant s a)

a)

Hours (h) may be used as the unit of time instead of seconds for all quantities involving time (i.e. for time periods as well as for air change rates), but in that case the unit of energy is (W•h) instead of J.

b)

The unit depends on the type of energy carrier.

c) _{The unit depends on the indicator chosen, see EN 15217 clause 5.} d) _{Coefficients have dimensions; factors are dimensionless.}

e) _{Including primary energy and energy carriers; note that for heat the symbol}_Q_{and for auxiliary} energy and work the symbol W is used.

Table 2 — Subscripts

Subscript Term Subscript Term

0 base, reference mn _{mean (time or space) a}

a air nd need

A _{other appliances a} nEPus not related to considered building services

an annual ngen without generation

aux auxiliary nrbl non-recoverable

avg time-average nrby nearby

B building nren non-renewable

bin bin nrvd not recovered

bm biomass ntdel net delivered

C _{cooling a} nused not used (in the same calculation step)

calc calculated nut non-utilised

CO2 CO2 emission off off

cr energy carrier oil oil

ctr control on on

CW _{cooling and DHW a} out output

day daily P primary energy

dc district cooling per for a period of time

del delivered pk peak

dh district heat Pnren non-renewable primary energy dhum _{dehumidification a} pol related to policy

dis distribution pr produced

distant distant Ptot total primary energy

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Table 2 (end)

DU dehumidification (system) pv solar electricity (photovoltaic)

e external; envelope rbl recoverable

el electricity rdel redelivered in a different calculation step

em emission red reduced

EPus all building services included in the energy performance assessment

ren renewable energy

est estimated rvd recovered

exp exported seas seasonal

f floor sens sensible

gas gas set setpoint

gen generation sf solid fuel

gn gains sol solar

grid from public network (grid) sp space

h hourly st storage

H _{heating a} sys system

HC _{heating and cooling a} T _{thermal a}

HCW _{heating, cooling and DHW a} t calculation step

ht heat transfer tmp temporary

HU _{humidification a} tot total

hum humidification (system) Tot _{total a}

HW _{heating and DHW a} tr transmission heat transfer

i,j,k indexes us use

in input used used in the same calculation step

int internal ut utilised

L lighting a V ventilation a

lat latent ve ventilation heat transfer

lf liquid fuel W _{domestic hot water (DHW) a}

ls losses wd wood

m monthly wk weekly

max maximum X any considered building service

meas measured Y any subsystem

min minimum z building zone

a type of energy use

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Table 3 — Abbreviations Abbreviation Term

AHU air handling unit

CHP combined heat and power DHW domestic hot water (system) ED external dimension

EP energy performance

EPBD Energy Performance of Buildings Directive ID internal dimension

OID overall dimension PV photo-voltaic

RER total renewable energy ratio

5 Framework of the assessment of energy performance of buildings

5.1 Routing

This standard provides the modular and over-arching framework for the assessment of energy performance of buildings.

This standard is the common basis for the calculated and measured energy performance and also for energy performance inspection, at whole building, at building units or building element level.

Depending on the application, all or some of the other standards related to the energy performance of buildings that cover other parts of the modular structure are needed.

For the assessment of the energy performance the following steps have to be followed:

1) Identification of the application (checking compliance, certificate, type of rating; see 5.2).

2) For overall energy performance assessment:

a) Specification of the building category or the building unit category or categories (e.g. residential building, office building, combined building, consisting of office and restaurant parts, ..) and the related standardised use patterns (see 7.2).

b) Specification of the building services (e.g. heating, cooling, lighting, ..) included in the energy performance (see 7.3).

c) Specification of the assessment boundaries (see 7.4).

d) Calculation or measurement of the energy balance at the assessment boundaries, conversion to primary energy or other metric (e.g. CO2 emission) see 7.5.

e) Aggregation to the energy performance and the renewable energy contribution (see 7.6).

1. For calculated overall energy performance (see the calculation routing in 8);

2. For calculated energy performance at building or system element level (see 7.7);

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5.2 Types and uses of ratings

This standard gives two principal options for energy rating of buildings:

 calculated energy rating;

 measured energy rating.

The calculated energy rating includes the building services as specified in 7.3 and applies to assumed operating conditions. If the measured energy rating (see 12) is not corrected to cover the same building services and assumed conditions, these two types of rating cannot be compared.

The calculated energy rating can be either:

 standard, based on standard climate, use, outdoor environment and occupant-related input data, as specified in this standard. This rating is called "design rating" when applied to a planned building;

 tailored, calculated with climate, occupancy, outdoor environment and occupant related data adapted to the actual building and the purpose of the calculation.

The types of rating are summarised in Table 4.

Table 4 — Types of ratings Type of rating Name of

rating

Input data

Use Climate Building Calculated (asset rating) Design Standard Standard Design

Standard Standard Standard Actual Tailored Depending on purpose Actual

Measured Operational Actual Actual Actual

The assessment method of the measured energy rating is given in 12.

National bodies determine:

 which type of rating applies for each building category and purpose of the energy performance assessment;

 under what conditions the design rating can be considered as or converted to a calculated energy rating for the actually realised building.

Default choices are given in Table A1.

6 The over-arching reference modular structure

The overarching reference modular structure is used to identify:

 all required parts of the assessment procedure and provide an overview;

 the modules covered by the standards and to support specifications given to standard writers of the modules;

 the connection between the modules (e.g: calculation, expression of the energy performance). The over-arching modular structure has four main areas as shown in Table 5:

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Table 5 – Modules main areas

Modules Area

M1 Overarching modules M2 Building (as such)

M3-M11 Technical Building Systems under EPBD M12-M13 Other systems or appliances (not under

EPBD)

Each module is divided into sub-modules, in such a way that, where possible and feasible, some symmetry is retained. Modules are identified with the codes defined in the following scheme:

Figure 1 – Summary of the main modular structure NOTE 1 See the accompanying Technical Report for more details and examples. NOTE 2 Standards may cover one or more modules.

NOTE 3 See 10, System structuring, as an illustration for the links between the modules. HEA TING COOLING VENTILA TION HUM

IDI-FICA TION DEHUM IDI- FICA TION

DOM ESTIC HOT WA TER LIGHTING

B UILDING A UTOM A TION & CONTROL B UILDIG SITE ELECTR. P ROD (PV, Wind, …) TRA NSP ORT SYSTEM S (elevato rs, escalato rs) OTHER B UILDING RELA TED A P P LIA NCES M1 OA M2 B M3 H M4 C M5 V M6 HU M7 DU M8 W M9 L M10 M11 M12 M13 1 General General 1 2

Common terms and definitions; symbols, units

and subscripts

Building Energy Needs void void void void 2

3 Applications (Free) Indoor Conditions

w ithout Systems void void void void 3

4 Ways to Express Energy Performance

Ways to Express Energy

Performance 4

5 Building Functions and Building Boundaries

Heat Transfer by

Transmission void 5

6 Building Occupancy and Operating Conditions

Heat Transfer by Infiltration

and Ventilation void void void 6

7

Aggregation of Energy Services and Energy

Carriers

Internal Heat Gains 7

9 Calculated Energy Performance

Building Dynamics (thermal

mass) void void void void 9

10 Measured Energy Performance

Measured Energy

Performance 10

11 Inspection Inspection 11

12 Ways to Express Indoor Comfort Building Management Systems 12 13 External Environment Conditions 14 Economic Calculations Inspection Measured Energy Performance Load dispatching and Operating conditions Measured Energy Performance < < s u b m o d u le

TECHNICAL BUILDING SYSTEMS

under EPBD not under EBPD

8

Load dispatching and Operating conditions 8 Building Partitioning Solar Heat Gains Generation & Control

Inspection < < s u b m o d u le BUILDING (as such) OVERARCHING

Emission & Control Emission & Control Ways to Express Energy

Performance

Ways to Express Energy Performance Maximum Load and Pow er

General General

Needs

Distribution & Control Distribution & Control

Storage & Control Storage & Control

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7 Assessment of energy performance of buildings

7.1 General

Default CEN options and values are given in Annex A. National annexes may replace Annex A. partly or totally

National annexes shall include the required data to perform the calculation according to given default CEN options and values.

EXAMPLE Climatic data are to be defined on a national and/or regional level, consequently relevant climatic data has to be presented in a national annex.

The provided data in the national annexes shall enable calculating the overall energy use of a building according to the default CEN values and option.

NOTE To provide flexibility to the Member States in the application of the CEN standards, clearly identified options are allowed. In order to progress on harmonization, reproducibility and transparency default CEN options are provided.

7.2 Building categories

The first step is to assess which building categories are included in the building or building unit and allocate each space of the building or building unit to one of these categories.

Default building categories are given in Table A.2.

NOTE Normally the allocation of a building category has legal implications, e.g. related to specific building regulations

As a second step, the following adjustment is made: parts of building having a different category and a useful floor area less than a percentage defined in Table A.11 of the floor area of an adjacent category, shall in the context of the assessment of the energy performance, be assumed to have the same category as the adjacent space. In case of more than one adjacent category, the category with the largest floor area shall be selected.

7.3 Building services

The assessment of the annual energy shall include the building services listed in Table A.3.

The annual energy use to provide the building services includes auxiliary energy and losses of all systems.

Other building services to be taken into account are optional (e.g. energy use for appliances, cooking, mechanical escalators, and elevators).

The needs for the considered building services (e.g. tapping patterns for DHW, internal air temperatures, occupancy, scenario's) and the recoverable losses shall be identified according to the relevant clauses of standards relating to module M 1-6.

7.4 Assessment boundaries

7.4.1 General principles

The assessment boundary is related to the assessed object (e.g. building, building units).

The rules for rating all building units separately, to rate only characteristic building units is to be defined on national level (see Annex A).

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Inside the assessment boundary the system losses are taken into account explicitly in the energy balance; outside the assessment boundary they are taken into account in the conversion factor applied to the energy carrier.

Energy can be imported or exported through the assessment boundary. The assessment boundary defines where the delivered and exported energy are evaluated.

The assessment boundary defines the energy balance.

Some of these energy flows can be quantified by meters (e.g. gas, electricity, district heating and water). For active solar, wind or water energy systems the incident solar radiation on solar panels or the kinetic energy of wind or water is not part of the energy balance of the building. Only the energy delivered by the generation devices, the auxiliary energy needed to supply the energy from the source (e.g. solar collector) to the building, and the thermal losses are taken into account in the energy balance.

For the assessment of the energy performance of a building or a building unit several geographical perimeters shall be considered:

 the conditioned space of the assessed building or building unit;

 the building site (“on site”);

 outside the building site (e.g. nearby or distant).

Lighting fitted outside of the building envelope is not part of the energy performance calculation.

Key:

a Assessment boundary S1 Conditioned space 1 PV (use energy balance) (needs energy certificate) 2 Wind b On-site S2, S3 Unheated space

c Nearby d Distant

Figure 2 – Geographical perimeters and assessment boundaries

Primary energy conversion factors are defined for each energy flow delivered or exported through the assessment boundary taking into account the origin for delivered and destination for exported. 7.4.2 The conditioned space of the assessed building or building unit

The conditioned space perimeter applies for the calculation of the energy needs and to the spaces related to the energy performance indicator.

1 S3 S1 1 1 2 S2 a c 1 2 d 3 b

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Only the considered conditioned surfaces or spaces shall be taken into account in the denominator when calculating the performance ratio of a building or building unit.

The reference dimensions to express the energy performance indicator are given in Table A.4.

Unconditioned (e.g. unheated) spaces are included in the conditioned space:

 If the unconditioned space is completely surrounded by conditioned spaces, or:

 if the ratio of the transmission heat transfer coefficient between the unconditioned space and the outdoor environment and the transmission heat transfer coefficient by between the unconditioned space and the adjacent conditioned space or spaces is smaller than the value given in Table A.5.

In this case the unconditioned space shall be assumed to be of the same category as the adjacent space. In case of more than one adjacent category, the category with the largest floor area shall be selected.

For existing buildings, for reasons of a fair and practical assessment: a space that is formally allocated as unconditioned spaces shall, in the context of the assessment of the energy performance, be assumed to be a conditioned area, if this space is in practice regularly occupied.

If an unheated space is regarded as conditioned space, then it shall be regarded as a conditioned space for the whole assessment (heating, cooling, lighting, etc.) in the denominator and the numerator of the energy performance assessment.

NOTE The allocation as conditioned area has an impact on both the assessed energy performance (numerator of the energy performance), as well as on the total conditioned floor area (denominator of the energy performance).

7.4.3 The building site (“on site”)

In case of building sites with multiple buildings, the assessment boundary is related to the assessed object (e.g. building, building unit). If there are more buildings on the building site, all served by the site energy centre but assessed separately, than the system losses are still taken into account explicitly but divided according to the energy delivered to the different buildings.

Default options are given in Table A.6.

7.4.4 Outside the building site

The site perimeter applies to the energy carrier, to the delivered and exported energy use weighted by the primary energy factors.

Outside the assessment boundaries it is distinguished between: 1. “nearby”;

2. “distant”.

“Nearby” is defined as an energy source which can be used only at local or district level and requires specific equipment for the assessed building or building unit to be connected to it (e.g. district heating or cooling).

“Distant” is defined as all the other energy sources not included in the previous definition.

NOTE Outside the assessment boundary it can be differentiated on national level between “nearby” (local level) and “distant” (macro infrastructure level) when defining the primary energy factors or other metrics.