2010/31/EU - Directive 2010/31/eu of the European Parliament and of the Council of 19 May 2010 on the energy performance of buildings (recast)

This Technical Report refers to EN 16947-1:2015, Building Management System - Module M10-12.
It contains information to support the correct understanding, use and national adaption of EN 16947-1.
This Technical Report does not contain any normative provision.

This European Standard specifies operational activities, overall alarming, fault detection and diagnostics, reporting, monitoring, energy management functions, functional interlocks and optimizations to set and maintain energy performance of buildings.
Table 1 shows the relative position of this standard within the set of EPB standards in the context of the modular structure as set out in prEN ISO 52000 1:2015.
NOTE 1   In FprCEN ISO/TR 52000 2:2014 the same table can be found, with, for each module, the numbers of the relevant EPB standards and accompanying Technical Reports that are published or in preparation.
NOTE 2   The modules represent EPB standards, although one EPB standard may cover more than one module and one module may be covered by more than one EPB standard, for instance a simplified and a detailed method respectively.
Table 1 - Position of this standard (in casu M10–12), within the modular structure of the set of EPB standards
...

This document provides a transparent framework for reporting on the choices related to the procedure
to determine primary energy factors (PEFs) and CO2 emission coefficients for energy delivered to and
exported from the buildings as described in EN ISO 52000-1.
This document specifies the choices to be made to calculate the PEF(s) and CO2 emission coefficients
related to different energy carriers. PEFs and CO2 emission coefficients for exported energy can be
different from those chosen for delivered energy.
This document is primarily intended for supporting and complementing EN ISO 52000-1, as the latter
requires values for the PEFs and CO2 emission coefficients to complete the EPB calculation. But it can also
be used for other applications.
NOTE The CO2 emission coefficients allow calculating greenhouse gas emissions. According to the choices
made, the CO2 emission coefficients represent only CO2 emissions or also other greenhouse gases.
Table 1 shows the position (marked by “X”) of this document within the modular structure as set out in
EN ISO 52000-1.
The modules represent EPB standards, although one EPB standard may cover more than one module and
one module may be covered by more than one EPB standard, for instance a simplified and a detailed
method respectively.

This document specifies requirements for indoor environmental parameters for thermal environment,
indoor air quality, lighting and acoustics and specifies how to establish these parameters for building
system design and energy performance calculations.
This European Standard includes design criteria for the local thermal discomfort factors, draught, radiant
temperature asymmetry, vertical air temperature differences and floor surface temperature.
This European Standard is applicable where the criteria for indoor environment are set by human
occupancy and where the production or process does not have a major impact on indoor environment.
This European Standard also specifies occupancy schedules to be used in standard energy calculations
and how different categories of criteria for the indoor environment can be used.
The criteria in this European Standard can also be used in national calculation methods. This standard
sets criteria for the indoor environment based on existing standards and reports listed under normative
references or in the bibliography.
This European Standard does not specify design methods, but gives input parameters to the design of
building envelope, heating, cooling, ventilation and lighting.

This document deals with the indoor environmental parameters for thermal environment, indoor
air quality, lighting and acoustic. The document explains how to use EN 16798-1 for specifying
indoor environmental input parameters for building system design and energy performance
calculations. The document specifies methods for long term evaluation of the indoor environment
obtained as a result of calculations or measurements. The document specifies criteria for
measurements which can be used if required to measure compliance by inspection. The
Document identifies parameters to be used by monitoring and displaying the indoor environment
in existing buildings. This document is applicable where the criteria for indoor environment are
set by human occupancy and where the production or process does not have a major impact on
indoor environment. The document explains how different categories of criteria for the indoor
environment can be used.

This document specifies requirements for indoor environmental parameters for thermal environment, indoor air quality, lighting and acoustics and specifies how to establish these parameters for building system design and energy performance calculations.
This European Standard includes design criteria for the local thermal discomfort factors, draught, radiant temperature asymmetry, vertical air temperature differences and floor surface temperature.
This European Standard is applicable where the criteria for indoor environment are set by human occupancy and where the production or process does not have a major impact on indoor environment.
This European Standard also specifies occupancy schedules to be used in standard energy calculations and how different categories of criteria for the indoor environment can be used.
The criteria in this European Standard can also be used in national calculation methods. This standard sets criteria for the indoor environment based on existing standards and reports listed under normative references or in the bibliography.
This European Standard does not specify design methods, but gives input parameters to the design of building envelope, heating, cooling, ventilation and lighting.
Table 1 shows the relative position of this standard within the set of EPB standards in the context of the modular structure as set out in EN ISO 52000 1.
NOTE 1   In CEN ISO/TR 52000 2 the same table can be found, with, for each module, the numbers of the relevant EPB standards and accompanying technical reports that are published or in preparation.
NOTE 2   The modules represent EPB standards, although one EPB standard may cover more than one module and one module may be covered by more than one EPB standard, for instance a simplified and a detailed method respectively. See also Clause 2 and Tables A.1 and B.1.

This document deals with the indoor environmental parameters for thermal environment, indoor air quality, lighting and acoustic. The document explains how to use EN 16798-1 for specifying indoor environmental input parameters for building system design and energy performance calculations. The document specifies methods for long term evaluation of the indoor environment obtained as a result of calculations or measurements. The document specifies criteria for measurements which can be used if required to measure compliance by inspection. The Document identifies parameters to be used by monitoring and displaying the indoor environment in existing buildings. This document is applicable where the criteria for indoor environment are set by human occupancy and where the production or process does not have a major impact on indoor environment. The document explains how different categories of criteria for the indoor environment can be used.

This European Standard describes the methods to calculate the ventilation air flow rates for buildings
to be used for energy calculations evaluation, heating and cooling loads.
This European Standard applies to buildings with:
-   Mechanical ventilation systems (mechanical exhaust, mechanical supply or balanced system);
-   Passive duct ventilation systems for residential and low-rise non-residential buildings;
-   Combustion appliances;
-   Windows opening by manual operation;
-   Kitchens where cooking is for immediate use (including restaurants)
This European Standard is applicable to hybrid systems combining mechanical and passive duct ventilation systems in residential and low-rise non-residential buildings.
This European Standard applies to buildings smaller than 100 m and rooms where vertical air temperature difference is smaller than 15 K.
The results provided by the standard are:
   the air flow rates entering or leaving a ventilation zone;
-   the air flow rates required to be distributed by the mechanical ventilation system, if present.
This European Standard is not applicable to:
-   Buildings with kitchens where cooking is not for immediate use
-   Buildings with automatic windows (or openings)
-   Buildings with industry process ventilation.
The definition of ventilation and airtightness requirements (as indoor air quality, heating and cooling, safety, fire protection…) is not covered by this standard.
The following information can be found in other standards and technical reports:
-   guidance to estimate pressure drops in ducts (CR 14378:2002)
Table 1 shows the relative position of this standard within the EN EPB package of standards.

1   Scope
This European Standard applies to the design and implementation of ventilation, air conditioning and room conditioning systems for non-residential buildings subject to human occupancy, excluding applications like industrial processes. It focuses on the definitions of the various parameters that are relevant for such systems.  
The guidance for design given in this standard and accompanying TR 13779 are mainly applicable to mechanical supply and exhaust ventilation systems. Natural ventilation systems or natural parts of hybrid ventilation systems are not covered by this standard. Reference is made to the Technical Report for informative guidance on the design of such systems.
Applications for residential ventilation are not dealt with in this standard. Performance of ventilation systems in residential buildings are dealt with in EN 15665 and CEN/TR 14788.
The classification uses different categories. For some values, examples are given and, for requirements, typical ranges with default values are presented. The default values given in this standard are not normative as such, and should be used where no other values are specified. Classification should always be appropriate to the type of building and its intended use, and the basis of the classification should be explained if the examples given in the standard are not to be used.
NOTE   Different standards may express the categories for the same parameters in a different way, and also the category symbols may be different.

1.1   This European Standard specifies the common methodology and the requirements for inspection of air conditioning systems in buildings for space cooling and/or heating and/or ventilation systems from an energy use standpoint to fulfil the EPBD requirements (Energy Performance of Buildings Directive 2010/31/EU). The methodology described in this European Standard deals with indoor climate problems that may be due to the systems inspected.
This European Standard applies to both residential and non-residential buildings equipped with:
-   air conditioning system(s) without mechanical ventilation; or
-   air conditioning system(s) with mechanical ventilation; or
-   natural and mechanical ventilation system(s).
This European Standard applies to:
-   fixed systems;
-   accessible parts that contribute to the cooling and mechanical ventilation services.
This European Standard is also applicable to some systems not covered by the Directive, such as:
-   fixed systems of less than 12 kW output;
-   ventilation-only systems.
The inspection of systems given in this European Standard is applicable to:
-   all types of comfort cooling and air conditioning systems. This includes air conditioning systems of an effective rated output of less than 12 kW not covered by Directive 2010/31/EU;
-   all types of ventilation systems that is to say mechanical, natural, hybrid (including mechanical and natural ventilation). Parts of this European Standard are also applicable to check ventilation requirements when there is no ventilation system.
The inspection of systems includes but is not limited to the following components:
-   reverse-cycle operation of air-conditioning equipment;
-   associated water and air distribution and exhaust systems that form a necessary part of the system;
-   controls that are intended to regulate the use of associated water and air distribution and exhaust systems.
Table 1 shows the relative position of this European Standard within the EN EPBD package of standards.
1.2   This European Standard is not applicable to:
-   qualification of the persons or organisation in charge of inspections;
-   frequency of the mandatory inspection (defined on national level);
-   components supporting the heating function (defined in EN XXXXX and the accompanying Technical Report CEN/TR XXXXX covering the inspection of heating-only systems using boilers).
1.3   The following information can be found in other standards or technical reports:
-   guidance regarding features affecting the frequency and duration of inspection are given in CEN/TR XXXXX-18;
-   procedures and methods for the inspection of boilers and heating systems are given in EN 15378 [5].

The scope of this European Standard is:
-   To define the procedure how the calculation methods to determine the temperatures, loads, energy demands for the cooling generation shall be utilised in the design process.
-   To describe the calculation methods to determine the temperatures, loads, energy demands for cooling generation.
-   To provide guidelines for the Member States for national implementations of this standard.
This standard covers the cooling generation calculation of air conditioning systems. It takes into account the cooling generation system, which can consist of compression and absorption and other types of generators. It does not cover the cooling emission, distribution and storage, which are covered by prEN 15316-2, 15316-3 and prEN XXXXX-15, respectively.
Table 1 shows the relative position of this standard within the EN EPB package of standards.

This standard covers energy performance calculation of storage systems used for ventilation systems.
This standard does not cover sizing or inspection of such storage systems.
Table 1 shows the relative position of this standard within the EN EPB package of standards.

This Technical Report refers to the standard EN 16798-15.
It contains information to support the correct understanding, use and national adaptation of this
standard.

Table 1 shows the relative position of this standard within the EN EPB set of standards.
(...)
This draft standard covers energy performance calculation of mechanical ventilation and air conditioning systems. It takes into account the generation (air handling unit) and distribution (duct system) parts. It does not cover the emission part (calculation of the required volume flow rates and/or supply air conditions), which is covered in prEN 16798-7 (revised EN 15242). A calculation method for compact ventilation systems with integrated heating/cooling generation, using a monthly or seasonal calculation time step, is provided in a separate standard prEN 16798-5-2.

This Technical Report refers to standard EN 16798-17:2017, module M4-11, M5-11, M6-11 and M7-11.
It contains information to support the correct understanding and use of this standard.
This Technical Report does not contain any normative provision.
Information regarding features affecting the frequency and duration of inspection is included in 5.2.

This Technical Report refers to the standard EN 16798-7.
It contains information to support the correct understanding and use of this standard.

This Technical Report refers to EN 16798-3.
It contains information to support the correct understanding and use of EN 16798-3.
This Technical Report does not contain any normative provision.
This Technical Report applies to the design and implementation of ventilation, air conditioning and
room conditioning systems for non-residential buildings subject to human occupancy, excluding
applications like industrial processes. It focuses on the definitions of the various parameters, which are
relevant for such systems.
The guidance for design given in this standard and its annexes are mainly applicable to mechanical
supply and exhaust ventilation systems, and the mechanical part of hybrid ventilation systems.
Furthermore general design principles of natural ventilation systems are introduced in Annex D.
Applications for residential ventilation are not dealt with in this technical report. Performance of
ventilation systems in residential buildings are dealt with in CEN/TR 14788.
The classification uses different categories. For some values, examples are given and, for requirements,
typical ranges with default values are presented. The default values given in this standard are not
normative as such, and should be used where no other values are specified. Classification should always
be appropriate to the type of building and its intended use, and the basis of the classification should be
explained if the examples given in the standard are not to be used.
NOTE Different standards might express the categories for the same parameters in a different way, and the
category symbols may be different.

This Technical Report refers to the standard EN 16798-13.
It contains information to support the correct understanding and use of this standard.

This Technical Report refers to standards EN 16798 5 1 and EN 16798 5 2.
It contains information to support the correct understanding and use of these standards.
This technical report does not contain any normative provision.

This standard covers the energy performance calculation of complete cooling systems. It gives a calculation method which defines how to collect the cooling energy requirements from the thermal zones and from the air handling units connected to a distribution system, and how to aggregate multiple distribution systems to an overall system energy requirement. It integrates the calculation of the emission and distribution losses and auxiliary energy. The required cooling energy to be extracted by the cooling generation system is calculated, considering cooling energy storage. It gives a method on how to dispatch the cooling energy provided by the cooling generation to different distribution systems, considering possible priorities.
This standard defines technical system related energy performance indicators for cooling systems.

This standard covers energy performance calculation of mechanical ventilation systems. It takes into account the generation (air handling unit) and distribution (duct system) parts. It does not cover the emission part (calculation of the required volume flow rates and/or supply air conditions), which is covered in prEN 16798 7 (revised EN 15242).
A calculation method for air conditioning systems, using an hourly calculation time step, is provided in a separate standard prEN 16798-5-1.

This Technical Report refers to the standard EN 16798-9.
It contains information to support the correct understanding, use and national adaptation of this
standard.

This European Standard is part of a series of standards on the method for calculation of system energy requirements and system efficiencies of space heating systems and domestic hot water systems.
This standard (prEN 15316-4-1) specifies:
-   required inputs;
-   a calculation method;
-   resulting outputs;
-   a method to take into account the energy performance of heat generation devices based on fuel combustion.
for space heating generation by combustion sub-systems (boilers, biomass), including control.
This standard also specifies methods for the calculation of:
-   thermal losses from the domestic hot water generation system;
-   recoverable thermal losses for space heating from the domestic hot water generation system;
-   auxiliary energy of the domestic hot water generation systems.
This standard specifies the energy performance calculation of water based heat generation sub-systems including control based on combustion of fuels ("boilers"), operating with conventional fossil fuels as well as renewable fuels. This standard does not cover sizing or inspection of boilers.
This standard is also applicable to heat generators for heating or for combined service as domestic hot water, ventilation, cooling and heating. Generators for domestic hot water only are taken into account into part M8-8.
This European Standard is the general standard on generation by combustion sub-systems (boilers, biomass) and is also intended for generation for domestic hot water production and/or space heating. These values are input data for calculation of the overall energy use according to prEN 15603 and prEN 15316-1.

This Technical Report (CEN/TR 15316-6-5) specifies details for EN 15316-4-2 and gives additional information for the application of EN 15316-4-2.

This Technical Report (CEN/TR 15316-6-8) specifies details for EN 15316-4-5 and gives additional information for the application of EN 15316-4-5.

This standard defines the determination of energy indicators of district energy systems. District energy systems may be district heating, district cooling or other district energy carriers.

This Technical Report (CEN/TR 15316-6-7) specifies details for EN 15316-4-4 and gives additional information for the application of EN 15316-4-4.

This Technical Report (CEN/TR 15316-6-4) specifies details for EN 15316-4-1 and gives additional information for the application of EN 15316-4-1.

This standard defines a method for the performance assessment of building-integrated cogeneration units by the calculation of the electricity production, thermal output and recoverable losses. Such units are commonly known as micro or small scale cogeneration, or micro or small scale CHP.
This standard deals with heat generators for heating or for combined domestic hot water and heating services.
The calculation is based on the performance characteristics of the units, defined in product standards, and on operation conditions such the needed heat output.

The standard (prEN 15316-4-3) specifies  the:
-   required inputs;
-   calculation method;
-   required and resulting outputs,
for heat generation systems, thermal solar systems ( for space heating, domestic hot water production and the combination of both) and for photovoltaic systems applied in buildings.
Within this standard 6 methods are specified each method has its own range of applicability.
-   Method 1,
is applicable for solar domestic hot water systems characterized by EN 12976 (factory made) or EN 12977 2 (custom built).
The main output of the method is the solar heat and back up heat contribution to the requested heat use.
-   Method 2,
is applicable for systems for domestic hot water and / or space heating with components characterized by EN 12975-2 and EN12977-3 or EN12977-4 with a monthly calculation time step.
The main output of the method is the solar heat and back up heat contribution to the requested heat use.
-   Method 3,
is applicable for systems for domestic hot water and / or space heating with components characterized by EN 12975-2 with an hourly calculation time step.
The main output of the method is collector loop heat supplied to the heat storage.
-   Method 4,
is applicable for photovoltaic systems with components characterized by standards and with an annual calculation time step.
The output of the method is the produced electricity.
-   Method 5,
is applicable for photovoltaic systems with components characterized by standards and with a monthly calculation time step.
The output of the method is the produced electricity.
-   Method 6,
is applicable for photovoltaic systems with components characterized by standards and with a calculation time step.
The output of the method is the produced electricity.
These three last calculation methods do not take into account:
-   electrical storage;
-   PV/thermal photovoltaic systems.
Primary energy savings and CO2 savings, which can be achieved by photovoltaic systems compared to other systems, are calculated according to prEN 15603.
NOTE   Standards linked to the methods are listed in Annex C.

This Technical Report (CEN/TR 15316-6-6) specifies details for EN 15316-4-3 and gives additional information for the application of EN 15316-4-3.

This Technical Report (CEN/TR 15316-6-9) specifies details for EN 15316-4-8 and gives additional information for the application of EN 15316-4-8.

This standard is part of a series of standards on the method for calculation of system energy requirements and system efficiencies.
The scope of this specific part is to standardise the:
-   required inputs;
-   calculation method;
-   resulting outputs,
for space heating generation by:
-   air heating systems, including control;
-   overhead radiant heating systems for non-domestic use, including control; and
-   stoves.
This standard does not apply to heating systems that utilise water as a heat transfer medium.
Other heat generation systems such as boilers, heat pumps and others are covered in other sub modules of part M3 8.

This Technical Report (CEN/TR 15316-6-3) specifies details for EN 15316-3 and gives additional information for the application of EN 15316-3.

The purpose of this standard is to specify the applications, functionality set and application performance for electronic individual zone control equipment. The applications are for cooling and hot water or electrical heating as described in Annex B. This standard applies specifically to individual zone control equipment for maintaining temperature, humidity and air flow as a function of occupancy and demand operated with auxiliary electrical energy. Information required for the operation of the equipment may be processed using either analogue or digital techniques or a combination of both. Safety requirements remain unaffected by this standard. This standard refers to the input and output requirements of the controller and not of the input and output devices as e. g. sensors and actuators. This standard covers fixed-function, configurable and programmable controllers. The control equipment may or may not be connected to a data-network however communications aspects are not covered by this standard. These devices could be applied for any kind of building, intermittent or non-intermittent occupation, residential or non residential (see Annex B).

This Technical Report (CEN/TR 15316-6-2) specifies details for EN 15316-2 and gives additional information for the application of EN 15316-2.

This Technical Report (CEN/TR 12831-2) specifies details for EN 12831-1 and gives additional information for the application of EN 12831-1.

This Standard applies to electronic control equipment for heating systems with water as the heating medium and a flow water temperature up to 120 °C. This control equipment controls and regulates the distribution and/or the generation of heat in relation to the outside temperature and time and other reference variables. This standard covers also controllers which contain an integrated optimum start or an optimum start-stop control function. Safety requirements on heating systems remain unaffected by this standard. The dynamic behaviour of the valves and actuators are not covered in this standard. A multi-distribution and/or multi-generation system needs a coordinated solution to prevent undesired interaction and is not part of this standard.

This Standard specifies:
-   a structured list of control, building automation and technical building management functions which contribute to the energy performance of buildings;
-   a method to define minimum requirements regarding the control, building automation and technical building management functions to be implemented in buildings of different complexities;
-   factor based method to get a first estimation of the effect of these functions on typical buildings types and use profiles;
-   detailed methods to assess the effect of these functions on a given building. These methods enable to introduce the contribution of these functions to the calculations of energy performance ratings and indicators calculated by the relevant standards
- controls related identifiers for technical building systems

This Technical Report (CEN/TR 12831-4) specifies details for EN 12831-3 and gives additional information for the application of EN 12831-3.

This standard specifies methods to assess the energy performance to provide heating and domestic hot water to a building based on measurements.
This standard covers the assessment of the heating and domestic hot water energy performance of a building or of building elements based on measurements. This includes:
-   assessment of the heating and domestic hot water performance of the building based on measurement of the amount of delivered energy carriers;
-   assessment of the energy performance of systems, subsystems and building elements, based on measurements.
This standard does not cover measured energy performance on ventilation, cooling, air conditioning and lighting systems.
Figure 1 shows the relative position of this standard within the EPB standards.

This Technical Report (CEN/TR 15316-6-10) specifies details for EN 15316-5 and gives additional information for the application of EN 15316-5.

This European Standard defines guidelines for the inspection of installed an operational Functions of Building Automation, Controls and Technical Building Managment System including its configuration.

This standard provides a calculation method for the economic issues of heating systems and other systems that are involved in the energy demand and consumption of the building. It applies to all types of new and existing buildings.
The fundamental principles and terminology are explained in the standard.
The main items of the standard will be:
-   the definitions and the structure of the types of costs which shall be taken into account for the calculation of the economic efficiency of saving options in buildings;
-   data needed for definition of costs related to systems under consideration;
-   the calculation method(s);
-   expression of the result of the economic study.
This standard is part of the method for calculation of economic performance of energy saving options in buildings (e.g. insulation, better performing generators and distribution systems, efficient lighting, renewable sources, combined heat and power).
The scope of this specific part is to standardise:
-   the required inputs;
-   the required outputs;
-   the calculation formulas;
-   The type of energy systems concerned with the energy performance of the building.
NOTE   This is the revision of EN 15459:2009. The revision has been made consistent with the EU regulation on cost optimal. This revision includes the definition of payback for investment, and inclusion of the costs due to the deconstruction of the building. The method presenting annualised costs has been suppressed.

This Technical Report refers to prEN 15500-1, Control for heating, ventilating and air-conditioning applications - Part 1: Electronic individual zone control equipment - Modules M3-5,M4-5,M5-5.
It contains information to support the correct understanding, use and national adaption of prEN 15500-1:2015.
This Technical Report does not contain any normative provision.

This standard covers energy performance calculation of water based distribution systems for space heating, space cooling and domestic hot water.
This standard deals with the heat flux from the distributed water to the space and the auxiliary energy of the related pumps.
The heat flux and the auxiliary energy for pumps can be calculated at any time-step (hour, month and year). The input and output data are mean values of the time step.

This European Standard applies to equipment which controls scheduling heating systems. The signals can be processed by using either analogue or digital techniques, or both. The particular equipment to which this document applies covers both: · stand-alone fixed start-stop schedulers; · controllers which contain fixed start-stop scheduling function. It applies to basic and added start-stop control functions and sets minimum acceptable standards for functions, performance and documentation. NOTE The start-stop function can be integrated within a main control device. In this case the controller would be expected to this standard for scheduling function. Safety requirements on heating systems and heating control systems remain unaffected by this European Standard. The actuators and the dynamic behaviour of the valves are not covered in this European Standard. This control equipment may or may not be connected to a data network.

This standard is the general frame for the calculation of the energy performance of heating and domestic hot water systems. It specifies how to perform the calculation of the entire system using the calculation modules defined in the respective standards. It deals with common issues like operating conditions calculation and energy performance indicators.
This standard specifies the structure for the calculation of energy requirements of space heating and domestic hot water systems in buildings.
It standardises the required inputs and outputs in order to achieve a common European calculation method.
It allows the energy analysis of the different heating and Domestic hot water sub-systems including control (emission, distribution, storage, generation) by comparing the system losses and by defining system performance factors.
The performance analysis allows the comparison between sub-systems and make possible to monitor the impact of each sub-system on the energy performance of a building.
The calculation of the system losses of each part of the heating sub-systems is defined in subsequent standards
Ventilation systems are not included in this standard (e. g. balanced systems with heat recovery), but if the air is preheated or an air heating system is installed, the systems providing the heat to the AHU (Air Handling Unit) are covered by this standard.

This standard describes a method to calculate the power and the storage volume required for the dimensioning of domestic hot water systems (DHW). The applicability ranges from direct water heaters (no storage volume and a comparatively large effective heating power) to long term storage systems (e.g. seasonal storage with a comparatively small heating power and large storage volume).
This standard is applicable to the following water storage systems
-   storage charging systems characterized by a minimised mixing zone, e.g. layer-charging storage tanks or storage tanks with external heat exchangers, and
-   hot water tanks and storage systems characterized by a distinct mixing zone, e.g. storage systems with internal heat exchangers,
and for different uses.
The scope of the second part is to standardise the methods for determining the energy need for domestic hot water. This standard covers the domestic hot water needs in buildings.
The calculation of the energy needs for domestic hot water applies to a dwelling, a building or a zone of a building.
This standard also provides energy needs for different application cases of DHW-systems in hourly, monthly, and seasonal time steps, based on national default values.