BS-EN-ISO-13790-2004.pdf

BRITISH STANDARD BS EN ISO 13790:2004 Thermal performance of buildings Calculation of energy use for space heating The European Standard EN ISO 13790:2004 has the status of a British Standard ICS 91.140.10 ? Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 03:11:46 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN ISO 13790:2004 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 June 2004 © BSI 30 June 2004 ISBN 0 580 43985 2 National foreword This British Standard is the official English language version of EN ISO 13790:2004. The UK participation in its preparation was entrusted by Technical Committee B/540, Energy performance of materials, components and buildings, to Subcommittee B/540/1, European standards for thermal insulation, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN ISO title page, pages 2 to 63 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. DateComments Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 03:11:46 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM EN ISO 13790 June 2004 ICS 91.140.10 English version Thermal performance of buildings - Calculation of energy use for space heating (ISO 13790:2004) Performance thermique des bâtiments - Calcul des besoins d'énergie pour le chauffage des locaux (ISO 13790:2004) Wärmetechnisches Verhalten von Gebäuden - Berechnung des Heizenergiebedarfs (ISO 13790:2004) This European Standard was approved by CEN on 8 September 2003. CEN 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 Central Secretariat or to any CEN 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 CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels © 2004 CENAll rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 13790:2004: E Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 03:11:46 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN ISO 13790:2004 (E) 2 Contents Foreword3 Introduction.4 1Scope4 2Normative references5 3Terms and definitions .5 4Symbols and abbreviations9 5Outline of the calculation procedure and required data11 6Intermittent heating .15 7Heat loss (single zone calculation)16 8Heat gains.19 9Heat use21 10Annual heat use of the building24 11Energy for space heating24 12Report25 Annex A (normative) Application to existing buildings .27 Annex B (normative) Multi-zone calculation method .28 Annex C (normative) Intermittent heating Calculation of adjusted internal temperature29 Annex D (normative) Calculation with holiday period37 Annex E (normative) Heat loss of special envelope elements38 Annex F (normative) Solar gains of special elements42 Annex G (informative) Ventilation airflow rates 49 Annex H (informative) Data for solar gains53 Annex I (informative) Calculation of heat use for each heating mode57 Annex J (informative) Accuracy of the method.59 Annex K (informative) Conventional input data60 Annex ZA (informative) Normative references to international publications with their corresponding European publications.62 Bibliography63 Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 03:11:46 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN ISO 13790:2004 (E) 3 Foreword This document EN ISO 13790:2004 has been prepared by Technical Committee CEN/TC 89 “Thermal performance of buildings and building components”, the secretariat of which is held by SIS, in collaboration with Technical Committee ISO/TC 163, “Thermal performance and energy use in the built environment”, sub- committee 2, “Calculation methods”. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by December 2004, and conflicting national standards shall be withdrawn at the latest by December 2004. Annexes A to F are normative. Annexes G to K are informative. This document includes a Bibliography. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard : : Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 03:11:46 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN ISO 13790:2004 (E) 4 Introduction This standard is one of a series of calculation methods for the design and evaluation of thermal performance of buildings and building components. The calculation method presented in this standard is based on an energy balance taking account of internal and external temperature variations and, through a utilisation factor, of the dynamic effect of internal and solar gains. This method can be used for the following applications: 1) judging compliance with regulations expressed in terms of energy targets; 2) comparing the energy performance of various design alternatives for a planned building; 3) displaying a conventional level of energy performance of existing buildings; 4) assessing the effect of possible energy conservation measures on an existing building, by calculation of the energy use with and without the energy conservation measure; 5) predicting future energy resource needs on a national or international scale, by calculating the energy uses of several buildings representative of the building stock. Reference can be made to other International Standards or to national documents for input data and detailed calculation procedures not provided by this standard. In particular, this applies to the calculation of the efficiency or the heat loss of the heating systems. Unlike EN 832, whose scope is restricted to residential buildings, this standard can be applied to both residential and non-residential buildings. The most important changes in EN ISO 13790 compared to EN 832:1998, “Thermal performance of buildings - Calculation of energy use for heating - Residential buildings”, are: 1. Ventilation rates are calculated according to standards prepared by CEN/TC 156; 2. Clause 11 has been made simpler, and energy use is calculated from heat use according to existing International Standards or, by default, to national documents; 3. A normative method has been included to calculate the effect of intermittence. 4. New input data have been included for non-residential buildings, in particular for utilisation factors. For all these reasons, calculation using EN ISO 13790 gives results that may slightly differ from those obtained with EN 832. 1 Scope This standard gives a simplified calculation method for assessment of the annual energy use for space heating of a residential or a non-residential building, or a part of it, which will be referred to as “the building“. It does not apply to buildings with air conditioning systems likely to provide space cooling during the heating season. This method includes the calculation of: 1. the heat losses of the building when heated to constant internal temperature; 2. the annual heat required to maintain the specified set-point temperatures in the building; 3. the annual energy required by the heating system of the building for space heating, using heating system characteristics which are to be found in specific European or International Standards, or, by default, in national documents. Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 03:11:46 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN ISO 13790:2004 (E) 5 The building can have several zones with different set-point temperatures, and can have intermittent heating. The calculation period is the month. For residential buildings the calculation can also be performed for the heating season. Monthly calculation gives correct results on an annual basis, but the results for individual months close to the beginning and the end of the heating season can have large relative errors. Annex J provides some information on the accuracy of the method. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). EN ISO 7345:1995, Thermal insulation Physical quantities and definitions (ISO 7345:1987). EN ISO 13370:1998, Thermal performance of buildings Heat transfer via the ground Calculation methods (ISO 13370:1998). EN ISO 13789, Thermal performance of buildings Transmission heat loss coefficient Calculation method (ISO 13789:1999). 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. 3.1 calculation period time period for the calculation of heat losses and gains NOTE The calculation period is the month. For residential buildings the calculation can also be performed for the heating season. 3.2 external temperature temperature of external air NOTE For transmission heat loss calculations, the radiant temperature of the external environment is supposed equal to the external air temperature; long-wave transmission to the sky is considered in F.5. 3.3 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 ISO 7726, Ergonomics of the thermal environment - Instruments for measuring physical quantities. 3.4 set-point temperature internal temperature, as fixed by the control system in normal heating mode 3.5 set-back temperature minimum internal temperature to be maintained during reduced heating periods Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 03:11:46 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN ISO 13790:2004 (E) 6 3.6 adjusted internal temperature constant virtual internal temperature leading to the same heat loss as intermittent heating 3.7 heated space room or enclosure heated to a given set-point temperature 3.8 unheated space room or enclosure which is not part of the heated space 3.9 heat use heat to be delivered to the heated space by an ideal heating system to maintain the set-point temperature during a given period of time NOTEThe heat use can include additional building heat loss resulting from non-uniform temperature distribution and non-ideal temperature control, if they are taken into account by increasing the set-point temperature and not included in the heat loss due to the heating system. 3.10 energy use for space heating thermal energy to be delivered to the heating system to satisfy the heat use 3.11 intermittent heating heating pattern where normal heating periods alternate with reduced heating periods 3.12 modes of intermittence during intermittent heating, the heating system is operated according to either of the following modes: 3.12.1 normal mode: the heating system functions to maintain the internal temperature at the value it would have with continuous heating; 3.12.2cut-off mode: the heating system does not provide heat; 3.12.3reduced heating power mode: the heating system provides a heat flow rate lower than in normal heating; 3.12.4set-back mode: heat flow rate is controlled to maintain a set-back temperature; 3.12.5 boost mode: the heating system runs at full power in order to reach the set-point temperature at or before the end of the reduced heating period NOTEDepending on the control system, the boost mode can start according to two different strategies: a) fixed time boost: the start of the boost mode is fixed by the user; b) optimised boost: the time when the set-point internal temperature is recovered is fixed by the user, and the control system optimises the start of the boost mode, taking account of the external and internal temperatures. Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 20 03:11:46 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN ISO 13790:2004 (E) 7 3.13 heated zone part of the heated space with a given set-point temperature, throughout which the internal temperature is assumed to have negligible spatial variations 3.14 heat transfer coefficient heat flow rate between two zones divided by the temperature difference between both zones 3.15 heat loss coefficient heat transfer coefficient from the heated space to the external environment NOTE The heat loss coefficient of the building cannot be used when the multi-zone calculation method according to a