International Energy Agency LowEx Communities - Optimised Performance of Energy Supply Systems with Exergy Principles (Annex 64) Final Report The IEA EBC Annex 64 – LowEx Communities was a three year international research project which aims to demonstrate the potentials of low exergy thinking on a community level as energy and cost efficient solutions to achieve 100 % renewable and GHG emission-free energy systems. Central challenges are the identification of promising and efficient technical solutions for practical implementation. Aspects of future network management and business models for distribution and operation are as well essential for successful implementation and have been covered in the working phase. Aspects of transition management and policy will ensure the feasibility. The main objective of the annex is to demonstrate the potential of low exergy thinking on a community level as energy and cost efficient solutions. The intention is to reach these goals by providing and collecting suitable assessment methods (e.g. holistic balancing methods). Furthermore, guidelines, recommendations, best-practice examples and background material for designers and decision makers in the fields of building, energy production / supply and politics are provided. www.annex64.org Schmidt and Kallert (ed.) - LowEx Communities - Optimised Performance of Energy Supply Systems with Exergy Principles (Annex 64) Schmidt and Kallert (ed.) - LowEx Communities Optimised Performance of Energy ISBN 978-3-8396-1518-8 9 783839 615188 FRAUNHOFER VERLAG EBC ANNEX 64 FINAL REPORT International Energy Agency LowEx Communities - Optimised Performance of Energy Supply Systems with Exergy Principles (Annex 64) Final Report September 2019 Editors Fraunhofer Institute for Energy Economics and Energy System Technology IEE Dietrich Schmidt, [email protected] Anna Marie Kallert, [email protected] Authors Sabine Jansen, Michiel Fremouw - Delft University of Technology Forrest Meggers, Hongshan Guo - Princeton University Ralf-Roman Schmidt, Charlotte Maguerite - AIT Austrian Institute of Technology GmbH Ivo Martinac, Genku Kayo, Cong Wang - KTH – The Royal Institute of Technology Oddgeir Gudmundsson, Marek Brand, Klaus Lund Nielsen - Danfoss A/S Svend Svendsen, Maria Harrestrup, Xiaochen Yang - Technical University of Denmark Christina Sager-Klauss - Fraunhofer IEE Janybek Orozaliev, Isabelle Best - University of Kassel Marc Baranski, Roozbeh Sangi - E.ON Energy Research Center, RWTH Aachen University Saeed Saydi - Technical University Berlin Frank Dammel, Paul-Michael Falk - Technische Universität Darmstadt Eric Willems, Peter Op’t Veld - Huygen Engineers & Consultants Marta Giulia Baldi - University of Florence Paola Caputo, Frederica Zagarella - Politecnico di Milano Siir Kilkis - The Scientific and Technological Research Council of Turkey FRAUNHOFER VERLAG The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliografic data is available in the Internet at www.dnb.de. Printing and Bindery: Mediendienstleistungen des Fraunhofer-Informationszentrum Raum und Bau IRB, Stuttgart Printed on acid-free and chlorine-free bleached paper. All rights reserved; no part of this publication may be translated, reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the written permission of the publisher. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trade- marks. The quotation of those designations in whatever way does not imply the conclusion that the use of those designations is legal without the consent of the owner of the trademark. © by Fraunhofer Verlag, 2019 ISBN 978-3-8396-1518-8 Fraunhofer Information-Centre for Regional Planning and Building Construction IRB P.O. 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Participating countries in EBC: Australia, Austria, Belgium, Canada, P.R. China, Czech Republic, Denmark, Finland, France, Germany, Ireland, Italy, Japan, Republic of Korea, the Netherlands, New Zealand, Norway, Portugal, Singapore, Spain, Sweden, Switzerland, United Kingdom and the United States of America. Cover photo: City of Kassel EBC ANNEX 64 FINAL REPORT Table of contents Executive Summary 4 Abbreviations 6 Definitions 8 1 Preface 10 1.1 The International Energy Agency (IEA) 10 1.2 The IEA Energy in Buildings and Communities Programme (EBC) 10 1.3 The IEA EBC Annex 64 – LowEx Communities 12 1.4 Operating Agent 13 2 Introduction 16 2.1 Background and Motivation 16 2.2 The LowEx Approach for Communities 16 2.3 Target groups 17 2.4 Main objectives and layout of this report 17 3 Exergy Thinking & Exergy analysis framework 19 3.1 Exergy as an indicator for sustainable community energy systems 19 3.2 The role of exergy in the different phases of developing community energy systems 23 3.3 Low-ex Design Principles for pre-planning of community energy systems 24 3.4 Simplified exergy analysis: ten steps 27 3.5 Summary and conclusions on exergy thinking 32 4 LowEx supply technologies 34 4.1 Building typologies and demand 34 4.2 Interface of demand and source – examples for centralised and decentralised community supply 38 4.3 Description of source and supply technologies 43 4.4 Conclusion 49 5 Case Studies across scales 50 5.1 Introduction 50 5.2 Building scale 51 5.3 District Scale 52 5.4 City Scale 59 5.5 Business Models - Austrians district heating business model 2.0 61 5.6 Summary and conclusions 64 6 Models and tools 66 6.1 Collection of Methods, Models, and Tools 67 6.2 Summary and overview of the collected methods, models and tools 75 6.3 SWOT Analysis of the tools 76 7 Conclusions 81 8 References 84 Appendix A: IEA EBC Annex 64 Participants 92 Appendix B: Additional information on case studies 94 Appendix C: Additional information on Tools and Models 97 EBC ANNEX 64 FINAL REPORT TABLE OF CONTENTS 3 Executive Summary The energy demand of the building sector for heating has to be carried out from generation to final use in and cooling is responsible for more than one third order to reduce significantly the share of primary or of the final energy consumption in Europe and wor- high-grade fossil energy used and to optimise exer- ldwide. Commonly, this energy is provided through gy efficiency. In practical implementation, advanced different fossil fuel based systems. These combus- technologies and innovative supply concepts must be tion processes cause greenhouse gas (GHG) emissi- adapted and further developed to realise the iden- ons and are regarded as one of the core challenges tified potentials together with the involved industry in fighting climate change and realizing the energy partner (system provider and consultants). transition. While a lot has already been achieved, especially regarding the share of renewables in the On the community scale, different types of supply sys- electricity sector, there are still large potentials in tems require different supply temperatures. To obtain the heating sector. Exploiting these potentials and the maximum output from a given primary energy synergies requires an overall analysis of the energy flow, different temperature levels can e.g. be casca- conversion processes within communities to achieve ded according to the requirements of the building ty- a holistic understanding of these processes. pology and technology. This demands an intelligent arrangement and management of the temperature The term exergy is important in this understanding levels and flows within the system. Bi-directional because it takes account of the ‘energy quality’ and concepts and short term storage can be elements of can help to ensure that the most appropriate source a system which is not only energy efficient, but also is used for a given application. For example in space exergy efficient. Since high-exergy resource electri- heating processes natural gas, a high quality / high city plays a special role within the evaluation proces- exergy source, is often burned to heat water to 70- ses, it is feasible, on an exergy basis, to weigh the im- 80 °C which is in turn used for a low exergy applicati- pact of extra electricity use, for instance for pumping on of heating rooms in a home to 20 °C. The same gas or ventilation, on a thermodynamically correct basis could be burned to deliver temperatures of 1,000 °C against the heat and cold applications. On this basis, a in industrial processes and the waste heat from such discussion on a proper and workable set of indicators processes can be