ISO INTERNATIONAL STANDARD 17742 First edition 2015-08-15 Energy efficiency and savings calculation for countries, regions and cities Calcul de I'efficacite énergetique et des économies d'energie pour les pays, villes et regions Reference number ISO 17742:2015(E) ISO @ ISO 2015 IS0 17742:2015(E) COPYRIGHTPROTECTEDDOCUMENT IS0 2015, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISo at the address below or ISo's member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8. CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 [email protected] www.iso.org i @ IS0 2015 - All rights reserved IS0 17742:2015(E) Contents Page Foreword ..V Introduction. ..i. 1 Scope. 2 Terms and definitions 3 Savings to be calculated 3.1 General .7 3.2 Types of savings to be calculated 3.2.1 Energysavingsaspartofenergyconsumptiondevelopment 7 3.2.2 Contributionstochange of varioustypes of energy savings 3.2.3 Savings types for different cases. .10 3.3 Methods,applications,and calculated savings ..11 3.3.1 Indicator-based calculation method ..11 3.3.2 Hidden structure effects in the indicator-based method .12 3.3.3 ..12 Measure-basedcalculationmethod 3.3.4 Energy baseline and additional savings in the measure-based method .13 3.3.5 Aggregated resultsof indicator-based and measure-based methods .13 3.3.6 Demarcation and integration of indicator-based and measure-based methods...14 3.3.7 Incorporationofotherpolicies thataffectenergy consumption .14 Indicator-based savings calculations. ..15 4 Indicators and calculation of savings ..15 4.1 4.1.1 Energy efficiency indicators. .15 4.1.2 Structure effects and disaggregation .15 4.1.3 Indicator choice and savings definition ..16 4.2 General calculation of indicator-based energy savings .16 4.2.1 Calculation approach ..16 4.2.2 Step1: Choice of indicator types ..17 4.2.3 Step2: Calculation ofindicatorvalues. .17 4.2.4 Step3:Calculation of energy savingsper indicator 20 4.3 Computational issues in the calculation of indicator-based savings 21 4.3.1 .21 General. 4.3.2 Variants of the calculation method .22 4.3.3 Energy consumptionunits .23 4.3.4 Overall indicator-based energy savings. .24 4.4 Reliability of saving figures .24 4.4.1 Indicators resulting in negative savings .24 4.4.2 The quality of indicator-based energy-saving figures .24 5 Measure-based savings calculations. .26 5.1 Measures and calculation of savings. .26 5.1.1 Elementaryunit ofaction and unitary energy savings .26 5.1.2 Energy baseline options for end-user actions 27 5.1.3 Savings types from measure-based calculations .28 5.2 General calculation of measure-based energy savings. 29 5.2.1 Calculationapproach 29 5.2.2 Step 1: Calculation of unitary gross annual energy savings .31 5.2.3 Step 2: Calculation of total gross annual energy savings .36 5.2.4 Step 3: Calculation oftotal (net)annual energy savings ...38 5.2.5 Step 4: Calculation of remaining energy savings for the calculation year ..40 5.2.6 Calculation of overall measure-based energy savings, taken into accountoverlap 5.3 Reliability of calculated savings ..41 AnnexA(informative)Examplesofenergyefficiencyindicators ..43 Annex B (informative) Level of detail and data handling in measure-based calculations ..51 @ IS0 2015 - All rights reserved ili IS0 17742:2015(E) Bibliography 53 iv IS0 2015-All rights reserved IS0 17742:2015(E) Foreword Iso (theInternational Organization for Standardization) is a worldwidefederation ofnational standards bodies (iso member bodies). The work of preparing International Standards is normally carried out throughIsotechnicalcommittees.Eachmemberbodyinterestedinasubjectforwhichatechnical committee has been establishe