Selected Papers from SDEWES 2018 Conferences on Sustainable Development of Energy, Water and Environment Systems Neven Duić, Mário Costa, Qiuwang Wang, Francesco Calise Poul and Alberg Østergaard www.mdpi.com/journal/energies Edited by Printed Edition of the Special Issue Published in Energies Selected Papers from SDEWES 2018 Selected Papers from SDEWES 2018 Conferences on Sustainable Development of Energy, Water and Environment Systems Special Issue Editors Neven Dui ́ c M ́ ario Costa Qiuwang Wang Francesco Calise Poul Alberg Østergaard MDPI • Basel • Beijing • Wuhan • Barcelona • Belgrade M ́ ario Costa University of Lisbon Portugal Poul Alberg Østergaard Aalborg University Denmark Special Issue Editors Neven Dui ́ c University of Zagreb Croatia Qiuwang Wang Xi’an Jiaotong University China Francesco Calise University of Naples Federico II Italia Editorial Office MDPI St. Alban-Anlage 66 4052 Basel, Switzerland This is a reprint of articles from the Special Issue published online in the open access journal Energies (ISSN 1996-1073) from 2018 to 2019 (available at: https://www.mdpi.com/journal/energies/special issues/SDEWES 2018) For citation purposes, cite each article independently as indicated on the article page online and as indicated below: LastName, A.A.; LastName, B.B.; LastName, C.C. 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Contents About the Special Issue Editors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix Preface to ”Selected Papers from SDEWES 2018 Conferences on Sustainable Development of Energy, Water and Environment Systems” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii Francesco Calise, Maria Vicidomini, M ́ ario Costa, Qiuwang Wang, Poul Alberg Østergaard and Neven Dui ́ c Toward an Efficient and Sustainable Use of Energy in Industries and Cities Reprinted from: Energies 2019 , 12 , 3150, doi:10.3390/en12163150 . . . . . . . . . . . . . . . . . . . 1 Verena Weiler, Jonas Stave and Ursula Eicker Renewable Energy Generation Scenarios Using 3D Urban Modeling Tools—Methodology for Heat Pump and Co-Generation Systems with Case Study Application Reprinted from: Energies 2019 , 12 , 403, doi:10.3390/en12030403 . . . . . . . . . . . . . . . . . . . . 29 Dominik Franjo Dominkovi ́ c and Goran Krajaˇ ci ́ c District Cooling Versus Individual Cooling in Urban Energy Systems: The Impact of District Energy Share in Cities on the Optimal Storage Sizing Reprinted from: Energies 2019 , 12 , 407, doi:10.3390/en12030407 . . . . . . . . . . . . . . . . . . . . 48 Ivan Smajla, Daria Karasalihovi ́ c Sedlar, Branko Drljaˇ ca and Lucija Juki ́ c Fuel Switch to LNG in Heavy Truck Traffic Reprinted from: Energies 2019 , 12 , 515, doi:10.3390/en12030515 . . . . . . . . . . . . . . . . . . . . 69 Daniele Testi, Paolo Conti, Eva Schito, Luca Urbanucci and Francesco D’Ettorre Synthesis and Optimal Operation of Smart Microgrids Serving a Cluster of Buildings on a Campus with Centralized and Distributed Hybrid Renewable Energy Units Reprinted from: Energies 2019 , 12 , 745, doi:10.3390/en12040745 . . . . . . . . . . . . . . . . . . . . 88 Albana Kona, Paolo Bertoldi and ̧ Siir Kılkı ̧ s Covenant of Mayors: Local Energy Generation, Methodology, Policies and Good Practice Examples Reprinted from: Energies 2019 , 12 , 985, doi:10.3390/en12060985 . . . . . . . . . . . . . . . . . . . . 105 Ahmed WA Hammad, Ali Akbarnezhad, Assed Haddad and Elaine Garrido Vazquez Sustainable Zoning, Land-Use Allocation and Facility Location Optimisation in Smart Cities Reprinted from: Energies 2019 , 12 , 1318, doi:10.3390/en12071318 . . . . . . . . . . . . . . . . . . . 134 Daniel Hoehn, Mar ́ ıa Margallo, Jara Laso, Isabel Garc ́ ıa-Herrero, Alba Bala, Pere Fullana-i-Palmer, Angel Irabien and Rub ́ en Aldaco Energy Embedded in Food Loss Management and in the Production of Uneaten Food: Seeking a Sustainable Pathway Reprinted from: Energies 2019 , 12 , 767, doi:10.3390/en12040767 . . . . . . . . . . . . . . . . . . . . 157 Hugo Sakamoto, Fl ́ avia M. Ronquim, Marcelo Martins Seckler and Luiz Kulay Environmental Performance of Effluent Conditioning Systems for Reuse in Oil Refining Plants: A Case Study in Brazil Reprinted from: Energies 2019 , 12 , 326, doi:10.3390/en12020326 . . . . . . . . . . . . . . . . . . . . 176 Marco Gambini, Michela Vellini, Tommaso Stilo, Michele Manno and Sara Bellocchi High-Efficiency Cogeneration Systems: The Case of the Paper Industry in Italy Reprinted from: Energies 2019 , 12 , 335, doi:10.3390/en12030335 . . . . . . . . . . . . . . . . . . . . 190 v Chenyi Xu, Zhichun Liu, Shicheng Wang and Wei Liu Numerical Simulation and Optimization of Waste Heat Recovery in a Sinter Vertical Tank Reprinted from: Energies 2019 , 12 , 385, doi:10.3390/en12030385 . . . . . . . . . . . . . . . . . . . . 211 Birol Kılkı ̧ s Development of an Exergy-Rational Method and Optimum Control Algorithm for the Best Utilization of the Flue Gas Heat in Coal-Fired Power Plant Stacks † Reprinted from: Energies 2019 , 12 , 760, doi:10.3390/en12040760 . . . . . . . . . . . . . . . . . . . . 230 Shicheng Wang, Chenyi Xu, Wei Liu and Zhichun Liu Numerical Study on Heat Transfer Performance in Packed Bed Reprinted from: Energies 2019 , 12 , 414, doi:10.3390/en12030414 . . . . . . . . . . . . . . . . . . . . 249 Ainur Munirah Hafizan, Jiˇ r ́ ı Jarom ́ ır Klemeˇ s, Sharifah Rafidah Wan Alwi, Zainuddin Abdul Manan and Mohd Kamaruddin Abd Hamid Temperature Disturbance Management in a Heat Exchanger Network for Maximum Energy Recovery Considering Economic Analysis Reprinted from: Energies 2019 , 12 , 594, doi:10.3390/en12040594 . . . . . . . . . . . . . . . . . . . . 271 Szymon Kuczy ́ nski, Mariusz Łaciak, Andrzej Olijnyk, Adam Szurlej and Tomasz Włodek Techno-Economic Assessment of Turboexpander Application at Natural Gas Regulation Stations Reprinted from: Energies 2019 , 12 , 755, doi:10.3390/en12040755 . . . . . . . . . . . . . . . . . . . . 301 Grzegorz Ligus, Daniel Zaj ą c, Maciej Masiukiewicz and Stanisław Anweiler A New Method of Selecting the Airlift Pump Optimum Efficiency at Low Submergence Ratios with the Use of Image Analysis Reprinted from: Energies 2019 , 12 , 735, doi:10.3390/en12040735 . . . . . . . . . . . . . . . . . . . . 322 Aneta Sapi ́ nska-Sliwa, Marc A. Rosen, Andrzej Gonet, Joanna Kowalczyk and Tomasz Sliwa A New Method Based on Thermal Response Tests for Determining Effective Thermal Conductivity and Borehole Resistivity for Borehole Heat Exchangers Reprinted from: Energies 2019 , 12 , 1072, doi:10.3390/en12061072 . . . . . . . . . . . . . . . . . . . 341 Luca Martinelli, Matteo Volpato, Chiara Favaretto and Piero Ruol Hydraulic Experiments on a Small-Scale Wave Energy Converter with an Unconventional Dummy Pto Reprinted from: Energies 2019 , 12 , 1218, doi:10.3390/en12071218 . . . . . . . . . . . . . . . . . . . 364 Halina Pawlak-Kruczek, Mateusz Wnukowski, Lukasz Niedzwiecki, Michał Czerep, Mateusz Kowal, Krystian Krochmalny, Jacek Zg ́ ora, Michał Ostrycharczyk, Marcin Baranowski, Wilhelm Jan Tic and Joanna Guziałowska-Tic Torrefaction as a Valorization Method Used Prior to the Gasification of Sewage Sludge Reprinted from: Energies 2019 , 12 , 175, doi:10.3390/en12010175 . . . . . . . . . . . . . . . . . . . . 376 Michał Gli ́ nski, Carsten Bojesen, Witold Rybi ́ nski and Sebastian Byku ́ c Modelling of the Biomass mCHP Unit for Power Peak Shaving in the Local Electrical Grid Reprinted from: Energies 2019 , 12 , 458, doi:10.3390/en12030458 . . . . . . . . . . . . . . . . . . . . 394 Abul Kalam Hossain and Abdul Hussain Impact of Nanoadditives on the Performance and Combustion Characteristics of Neat Jatropha Biodiesel Reprinted from: Energies 2019 , 12 , 921, doi:10.3390/en12050921 . . . . . . . . . . . . . . . . . . . . 408 vi Sara Restrepo-Valencia and Arnaldo Walter Techno-Economic Assessment of Bio-Energy with Carbon Capture and Storage Systems in a Typical Sugarcane Mill in Brazil † Reprinted from: Energies 2019 , 12 , 1129, doi:10.3390/en12061129 . . . . . . . . . . . . . . . . . . . 424 Mariusz Ta ́ nczuk, Robert Junga, Alicja Kolasa-Wi ę cek and Patrycja Niemiec Assessment of the Energy Potential of Chicken Manure in Poland Reprinted from: Energies 2019 , 12 , 1244, doi:10.3390/en12071244 . . . . . . . . . . . . . . . . . . . 437 Massimo Moser, Matteo Pecchi and Thomas Fend Techno-Economic Assessment of Solar Hydrogen Production by Means of Thermo-Chemical Cycles Reprinted from: Energies 2019 , 12 , 352, doi:10.3390/en12030352 . . . . . . . . . . . . . . . . . . . . 455 Szymon Kuczy ́ nski, Mariusz Łaciak, Andrzej Olijnyk, Adam Szurlej and Tomasz Włodek Thermodynamic and Technical Issues of Hydrogen and Methane-Hydrogen Mixtures Pipeline Transmission Reprinted from: Energies 2019 , 12 , 569, doi:10.3390/en12030569 . . . . . . . . . . . . . . . . . . . . 472 vii About the Special Issue Editors Neven Dui ́ c a full professor of power engineering in the Department of Energy, Power Engineering and Environment, Faculty of Mechanical Engineering and Naval Architecture in the University of Zagreb. He has been a member of the Postgraduate Study Committee since 2008 and is also the Chair for Ph.D. studies in the process-energy field. He was Chair of the Faculty Committee for International Projects from 2010 until 2014. Prof. Dui ́ c has published 108 original scientific papers and 7 review papers in scientific journals referenced in SCI and CC publications. Eighty-two of his scientific papers are Q1 papers, 39 of which are in the top 5% of journals in the category (according to ISI’s Web of Knowledge database). His papers were cited 2173 times in Scopus and 1779 times in Web of Knowledge. His H-index is 28 in Scopus and 24 in Web of Knowledge. According to CROSBI (the Croatian Scientific Bibliography) Prof. Dui ́ c has published the highest number of CC scientific papers in technical science since 2007. He has received a National Award for significant scientific achievement in 2016 in the field of engineering sciences. Prof. Dui ́ c has successfully led eight Ph.D. students and is currently mentoring five FMENA Ph.D. students. He has been a member of Ph.D. thesis juries for 11 Ph.D. students, seven of whom have gone on to study at foreign universities (Macquarie University, Aalborg University, University of Limerick, Instituto Superior Tecnico, University of Sarajevo, University of Beograd, University of Santander). He is an editor for Energy Conversion and Management (Q1), subject editor for the Q1 journal Energy, and a member of the editorial board of the following journals: Applied Energy (Q1), Clean Technologies and Environmental Policy (Q2), and Thermal Science (Q3). Since 2013, he has been the Editor-in-Chief of the Journal of Sustainable Development of Energy, Water and Environment Systems (JSDEWES), which was promptly and successfully indexed in the Scopus database. He has organised a series of conferences on the topic of sustainable development of energy, water and environment systems. He was also a member of organising, scientific, and programming committees of more than 57 research conferences. Prof. Dui ́ c is a coordinator of Croatian participation in two projects of the Croatian Foundation for Science and over 40 international scientific research projects. He is a national representative of Horizon 2020 projects for ERC/MSCA/FET. His main areas of interest are energy policy and planning, energy economics, sustainable development policy and resource planning, climate change mitigation, combustion engineering and modelling, research and innovation policy. Full CV: http://powerlab.fsb.hr/nduic/. M ́ ario Costa is a Full Professor in the area of environment and energy at the Mechanical Engineering Department of Instituto Superior T ́ ecnico. He graduated in Chemical Engineering at University of Coimbra in 1984, obtained his Ph.D. in Mechanical Engineering at Imperial College London in 1992, and his Habilitation in Mechanical Engineering at the Technical University of Lisbon in 2009. Currently, he teaches courses on thermodynamics, combustion, renewables energies, and integrated energy systems. He has supervised 8 Postdocs, 18 Ph.Ds., 75 M.Sc. and 35 Diploma students. He has participated in more than 50 national and international projects in the topic area of energy and environment and has (co-)authored a book, over 130 papers in international peer-reviewed journals, over 170 papers in international conferences, and has given more than 30 invited lectures at other universities and international symposia. Currently, he serves as Associate Editor of the Proceedings of the Combustion Institute and belongs to the Editorial Board of the Aerospace, Combustion and Flame, Energy Conversion and Management, Energies and Energy and Fuels. He was the recipient ix of the Caleb Brett Award of the Institute of Energy in 1991, the Sugden Award of the British Section of the Combustion Institute in 1991, the Pr ́ emio Cient ́ ıfico Universidade T ́ ecnica de Lisboa/Santander Totta in 2010, a Menc ̧ ̃ ao Honrosa Universidade de Lisboa/Santander Universidades in 2016, and of the Pr ́ emio Cient ́ ıfico Universidade de Lisboa/Santander Universidades in 2017. Qiuwang Wang is a full professor at the School of Energy and Power Engineering, Xi’an Jiaotong University. He received a B.Sc. in Fluid Machinery and a Ph.D. degree in Engineering Thermophysics from Xi’an Jiaotong University in 1991 and 1996, respectively. He was a visiting scholar at City University of Hong Kong (1998-1999), a guest professor at Kyushu University of Japan (2003), and a senior visiting scholar at Rutgers, The State University of New Jersey, USA since 2013. He is currently teaching the course titled “Heat Transfer” for undergraduate students, and the course “Advanced Heat Transfer” for graduate students, respectively. His research interests include heat transfer enhancement and its applications to engineering problems, high-temperature/high-pressure heat transfer and fluid flow, transport phenomena in porous media, numerical simulation, prediction & optimization, etc. He is a recipient of National Funds for Distinguished Young Scientists by the NSF of China (2010) and was granted the title of Changjiang Scholarship Chair Professor by the Ministry of Education of China (2013), leader of Innovation Team in Key Areas of Ministry of Science and Technology (2016), People Plan of Science and Technology Innovation Leading Talents (2017). His research team obtained the 2nd Grade National Award for Technological Invention of China (2015), and the National Science and Technology Progress Innovation Team Award of China (2017). He is now the China Delegate of Assembly for International Heat Transfer Conferences (AIHTC) (2015-), a member of Scientific Council of the International Centre for Heat and Mass Transfer (ICHMT) (2009-), a vice president of Chinese Society of Engineering Thermophysics in Heat and Mass Transfer (2010-), an Associate Editor of Heat Transfer Engineering since 2011, and is an Editorial Board Member for several international journals such as Energy Conversion and Management, Applied Thermal Engineering, Energies, Frontiers in Energy, etc. He is the Initiator and Chairman of International Workshop on Heat Transfer Advances for Energy Conservation and Pollution Control (IWHT) (which has been taking place every two years since 2011). He has also delivered more than 40 Invited/Keynote lectures in international conferences or foreign universities. He has also authored or co-authored 4 books and more than 180 international journal papers, and obtained 25 China Invention Patents and 2 US Patents. Francesco Calise was born in 1978 and graduated cum laude in mechanical engineering from the University of Naples Federico II, Italy, in 2002. He obtained his Ph.D. degree in mechanical and thermal engineering in 2006. From 2006 to 2014, he was a Researcher and Assistant Professor of applied thermodynamics at the University of Naples Federico II. In 2014, he took the position of Associate Professor at the University of Naples Federico II. His research activity has been mainly focused on the following topics: Fuel cells, advanced optimization techniques, solar thermal systems, concentrating photovoltaic/thermal photovoltaic systems, energy saving in buildings, solar heating and cooling, Organic Rankine Cycles, geothermal energy, dynamic simulations of energy systems, renewable Polygeneration systems, and many others. He was an invited lecturer for some courses/conferences in the UK and Finland. He teaches several courses on energy management and applied thermodynamics at the University of Naples Federico II for B.Sc., M.S. and Ph.D. students. He was a supervisor of several Ph.D. degree theses. He is a reviewer of about x 30 international journals. He was involved in several research projects funded by the EU and the Italian Government. He is a member of the Editorial Boards of 10 international journals. He was a Conference Chair and/or member of a scientific committee in several sessions in international conferences, promptly indeed in Scopus. He has organised several of the series of conferences on Sustainable Development of Energy, Water and Environment Systems and was a member of organising, scientific and programming committees of more than 57 other research conferences. Poul Alberg Østergaard is full professor in energy planning at the Department of Planning at Aalborg University, Denmark. He has worked within the field of energy planning since 1995, with a focus on the simulation of energy systems based on high penetrations of renewable energy sources as well as on the design of renewable energy system scenarios. Poul is engaged in various national and international research projects on 4th generation district heating, renewable energy investment strategies for Denmark in an interconnected European context, and smart renewable energy islands modelling tool development for energy system transition, for example. He has an h-index of 29 (Scopus, August 2019). In addition, he has extensive teaching and supervision experience at all levels and is the programme director of the M.Sc. programme in Sustainable Energy Planning and Management at Aalborg University and editor-in-chief of the International Journal of Sustainable Energy Planning and Management. He is or has also acted as guest/co-editor for a number of other energy-related journals including Energy, Energies, Applied Energy, Renewable Energy, Frontiers in Energy Research, and the Journal of Energy. He is one of the main organisers of the annual conference on 4th Generation District Heating and Smart Energy Systems. xi Preface to ”Selected Papers from SDEWES 2018 Conferences on Sustainable Development of Energy, Water and Environment Systems” Several countries have recently realized that the present paradigm of development in environmental and energy fields is unsustainable. As global awareness of environmental issues grows, governments worldwide are promoting policies which aim to limit the harmful effects of human development on the environment. In particular, these novel policies seek to address the rapid increase of the global temperature (especially in the polar regions) as well as to manage human plastic waste accumulating in seas. To resolve these issues will require a number of actions to be implemented; unfortunately, the recent COP 24 Conference was unsuccessful in establishing a global agreement to achieve these actions. In order for the upcoming 2020 COP 26 Conference to be successful in creating such an agreement, the scientific community must support the policymakers’ efforts. Within this framework, it is necessary to show the efforts of countries worldwide as they try to negotiate an agreement to increase the energy efficiency and reduce greenhouse gas (GHG) emissions. In addition, the research reports generated can provide quantitative measures of the necessary actions to be implemented in order to address sustainable and efficient energy use. Among other topics, the papers presented in this issue investigate innovations in novel efficient and environmentally friendly technologies mainly based on renewable energy sources. The study also highlights the different sectors involved in this task, such as energy conversion systems, urban areas, mobility, sustainability, water management, social aspects, etc. In this field, the Sustainable Development of Energy, Water and Environment Systems (SDEWES) conference provides the foremost forum for discussion on these topics. The 13th Sustainable Development of Energy, Water and Environment Systems Conference was held in Palermo, Italy in 2018. This Special Issue of Energies, precisely dedicated to 13th SDEWES Conference, features papers in three main topics: Energy policy and energy efficiency in urban areas, energy efficiency in industry, biomass and other miscellaneous energy systems. Neven Dui ́ c, M ́ ario Costa, Qiuwang Wang, Francesco Calise, Poul Alberg Østergaard Special Issue Editors xiii energies Review Toward an E ffi cient and Sustainable Use of Energy in Industries and Cities Francesco Calise 1 , Maria Vicidomini 1, *, M á rio Costa 2 , Qiuwang Wang 3 , Poul Alberg Østergaard 4 and Neven Dui ́ c 5 1 Department of Industrial Engineering, University of Naples Federico II, P.le Tecchio 80, 80125 Naples, Italy 2 IDMEC, Mechanical Engineering Department, Instituto Superior T é cnico, Universidade de Lisboa, 1649-004 Lisboa, Portugal 3 Key Laboratory of Thermo-Fluid Science and Engineering (Ministry of Education), Xi’an Jiaotong University, Xi’an 710049, China 4 Department of Planning, Aalborg University, Rendsburggade 14, 9000 Aalborg, Denmark 5 Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Ivana Luˇ ci ́ ca 5, 10000 Zagreb, Croatia * Correspondence: maria.vicidomini@unina.it; Tel.: + 39-081-768-5953 Received: 3 July 2019; Accepted: 14 August 2019; Published: 16 August 2019 Abstract: Several countries have recently realized that the present development paradigm is not sustainable from an environmental and energy point of view. The growing awareness of the population regarding environmental issues is pushing governments worldwide more and more to promote policies aiming at limiting harmful e ff ects of human development. In particular, the rapid increase of the global temperature, especially in the polar regions, and the management of human wastes, mainly plastic in seas, are some of the main points to be addressed by these novel policies. Several actions must be implemented in order to limit such issues. Unfortunately, the recent COP 24 Conference was not successful, but hopefully an agreement will be established in 2020 at the COP 26 Conference. The e ff ort performed by policymakers must be mandatorily supported by the scientific community. In this framework, this paper aims at showing that countries worldwide are trying to negotiate an agreement to increase energy e ffi ciency and reduce greenhouse gas (GHG) emissions. In addition, in this paper all the researchers reported can provide quantitative measures of the actions to be implemented in order to address a sustainable and e ffi cient use of energy. Here, innovations in terms of novel e ffi cient and environmentally friendly technologies mainly based on renewable energy sources have been also investigated. The study also highlights di ff erent sectors that have been involved for this aim, such as energy conversion systems, urban areas, mobility, sustainability, water management, social aspects, etc. In this framework, specific conferences are periodically organized in order to provide a forum for discussion regarding these topics. In this area the Sustainable Development of Energy, Water and Environment Systems (SDEWES) conference is the most ordinary conference. The 13th Sustainable Development of Energy, Water and Environment Systems Conference was held in Palermo, Italy in 2018. The current Special Issue of Energies, precisely dedicated to the 13th SDEWES Conference, is based on three main topics: energy policy and energy e ffi ciency in urban areas, energy e ffi ciency in industry and biomass and other miscellaneous energy systems. Keywords: sustainable development; renewable energy; biomass; energy e ffi ciency in industry 1. Introduction On 18 June 2018 negotiators from EU Parliament, Commission and Council reached a new agreement, focused on the development of a climate-friendly, a ff ordable and secure energy system for Energies 2019 , 12 , 3150; doi:10.3390 / en12163150 www.mdpi.com / journal / energies 1 Energies 2019 , 12 , 3150 the EU countries. With respect the previous proposals, which negotiated on the Energy Performance in Buildings Directive and on the revised Renewable Energy Directive, the new agreement is based on considerably strong goals from the energy e ffi ciency and emissions point of view: an increase of 32.5% of the energy e ffi ciency for 2030 and an emissions reduction of 40%. Considering the revision of Energy Building Performance Directive and 32% renewable energy target for the EU for 2030 (see STATEMENT / 18 / 4155), the defined targets will allow EU countries to obtain the goals set by the Paris Agreement and a clean energy transition. Furthermore, these targets could lead to several advantages for EU citizens, such as an enhanced security of the energy production systems, a more e ffi cient energy market, a more healthy and comfortable environment, a considerable reduction of energy bills [ 1 ]. To reach such ambitious aims, industry and academia must focus on the analysis and design of novel energy conversion systems and on the coupling of conventional and renewable energy systems [ 2 ]. Particularly, in this area numerous academics have been involved [ 3 ], analysing the sustainable development initiatives by considering the economic, environmental and energy aspects [ 4 ], and developing novel solutions for definite sectors [ 5 – 8 ]. Sustainable development involves extremely numerous di ff erent disciplines (renewable, water, energy, electrical and control engineering, etc.). At the beginning of this century, to approach this issue, the succession of the Sustainable Development of Energy, Water and Environment Systems (SDEWES) conferences was established. In 2018, the 13th SDEWES Conference (SDEWES 2018) was held in Palermo, Italy. The conference brought together 400 scientists, researchers, and experts in the field of sustainable development from around 50 countries. The conference is based on nine special sessions, one special event, three invited lectures and two panel debates with some of the most distinguished specialists of the sector. 80 posters and 330 papers were presented. The papers in this Special Issue (SI) are based on articles presented at SDEWES 2018 Conference, including di ff erent research issues, namely economic, technical, social and environmental studies, including works analysing the sustainability of energy, water, transport, food and environment production systems and their integration and interconnection. From 330 accepted manuscripts, 24 were selected for this SI of Energies in a continuation of an ongoing fruitful cooperation between Energies and SDEWES. The papers within the present SI can be classified into three main research fields: energy policy and energy e ffi ciency in urban areas (seven papers), energy e ffi ciency in industry (10 papers) and biomass and other miscellaneous energy systems (seven papers). 2. Background Numerous publications under other and this journal’s special sections or volumes dedicated to the SDEWES conference series are examined in this section. The studies included in this section are classified into the following research fields: energy policy and energy e ffi ciency in urban area, energy e ffi ciency in industry, biomass and other miscellaneous energy systems. 2.1. Energy Policy and Energy E ffi ciency in Urban Areas During the previous SDEWES conferences, several papers investigated the topic of energy policy and energy e ffi ciency in urban areas. Regarding this topic, numerous studies are available in the previous SDEWES SIs, adopting di ff erent approaches. Table 1 lists the topics, methodologies and main outcomes of the papers analysed in this subsection. 2 Energies 2019 , 12 , 3150 Table 1. Topics, methodologies and outcomes of the previous SDEWES papers dealing with energy policy and energy e ffi ciency in urban areas. Reference Topic Methodology Main Outcomes [9,10] Energy security Numerical model Energy Security indicators [11] EnergyPLAN Drought impacts on the future Finnish energy system [12] Quantitative geo-economic approach Geo-economic Index of Energy Security [13] Literature review Classic energy security concepts and energy technology changes. [14] Clean mobility sector EnergyPLAN Renewable energies optimization [15] Literature review Electrification and biofuels [16] Life cycle analysis Decision-makers support [17–19] Urban energy sustainability Comprehensive benchmarking SDEWES Index [20] Metropolitan areas sustainability Analytic hierarchy process Multi-criteria decision-making technique [21] Local water-energy-food nexus Quantitative analysis Relations between the food and water sectors [22] Water-energy nexus Life cycle analysis Renewable heating and solutions lighting [23] District heating systems Data analysis Main factors of the consumption [24] Nearly zero greenhouse city Dynamic simulation—EnergyPLAN Electricity and thermal energy costs [25] District analysis Dynamic simulation District sustainability indicators and new strategies for retrofitting [26] District heating and cooling networks Dynamic models Real dynamic controls [27] Techno-economic analysis Energy saving-targeted support mechanisms [28] Sustainable and e ffi cient waste management Numerical model Optimal selection and location [29] Tri-generation: municipal solid waste gasification Numerical model Positive economic performance For example, many studies focused on the problem of energy security becoming a critical issue in several EU countries [ 30 , 31 ]. In this framework, several works investigated the fuel poverty vulnerability of urban neighbourhoods [ 32 ], or the energy poverty for vulnerable households or the elderly [ 33 ] through the definition of several energy poverty indices, including the evaluation of the security of supply as well as the environmental and social components [ 34 ]. The topic of energy sources security in EU countries is also investigated by Matsumoto et al. [ 9 ]. In their work, the authors aim at understanding how the EU countries energy security has changed from the energy supply point of view between 1978 and 2014. The highest improvement of the overall energy security is identified in Denmark and Czech Republic due to their diversity of the origins of imports and primary energy sources. Through the calculation of special indicators, three kinds of countries were identified: (I) Countries with significantly high levels of moderate improvements and energy security over time; (II) countries with medium levels of energy security and moderate improvements; and (III) countries with significant improvements and low energy security levels. In particular, countries of the Groups 3 Energies 2019 , 12 , 3150 I and III were interesting because they show exemplar practices while the policies of Groups III, in leading to improvement, represent a guides for other countries. The energy security on the future Finnish energy system is investigated by Jääskeläinen et al. [ 11 ]. By considering that Nordic energy system is particularly dependent on hydropower production, the generation inadequacy in case of a severe drought is analysed by using the EnergyPLAN simulation tool. The indirect impacts of a drought in Finland’s neighbouring countries are also considered. During winter peaks an extreme drought shows relatively limited impacts on generation adequacy due to available hydropower storage. Anyway, by considering that Finland’s electricity market strongly depends on Sweden and Norway, the Finnish energy system would be a ff ected more strongly by an extreme drought via cross-border electricity trade. A novel geo-economic approach to quantitatively measure the energy security is proposed by Radovanic et al. [ 12 ]. By means of this new technique, based on the combination of sovereign credit rating and conventional indicators, authors defined a di ff erent Geo-economic Index of Energy Security for the measurement of the political, economic and financial stability. The performed measures of this new index are significantly di ff erent from the simple indicators evaluated by the conventional approach. The main conclusions of the authors highlight that the renewable energy production and energy dependence least a ff ect the energy security. Therefore, it is required to examine further the sovereign credit rating and to review the significance and type of the impact of the Energy Dependence indicator as a measure of energy security in general. Other paper regarded the energy security are reported in references [10,13]. Numerous papers focused on a clean transition of the mobility sector [ 35 ], in order to reduce emissions and energy demand. In fact, in the EU this sector covers about one third of the total energy consumption, so that important energy measures must be implemented. For example, Doroti ́ c et al. [14] modelled a novel solution to obtain a carbon neutral island, which uses 100% intermittent renewable energy sources and 100% share of smart charge vehicles, by means the integration of the vehicle-to-grid concept, power, heating and cooling sectors and renewable energy sources. The electrical marine transportation is also considered. The EnergyPLAN tool is adopted for this goal, in order to implement an optimization procedure aiming at selecting the power supply capacities of solar and wind technologies for the Croatian Island of Korˇ cula. Results show that the least-cost solution is based on an arrangement including 40 MW of wind and 6 MW of installed solar capacities. The combination with 22 MW of wind capacity and 30 MW of solar capacity shows the lowest quantity of total electricity import and export. Dominkovic et al. [ 15 ] performed a comprehensive literature review aiming at investigating a sustainable clean energy transition in the transportation sector. In this work, the authors state that to reduce the emissions of pollutants four fundamental solutions could be implemented, such as electricity, hydrogen, biofuels and synthetic fuels (electrofuels). The results show that in the EU the most important reduction of both energy demand and emissions can be obtained through the electrification of 72.3% of the transport energy demand. The authors estimated that biofuels could cover the remaining 3069 TWh. In addition, for the replacement of the fossil fuels, by renewable electrofuels, an additional demand of heat and electricity, equal to 925 TWh and 2775 TWh, is estimated. A novel method to support decision-makers in evaluating the uncertainty of the life cycle impacts of di ff erent bus technologies is developed by Harris et al. [ 16 ]. The advanced Technology Impact Forecasting method, integrating a life cycle model, allows the analysis of eleven scenarios including di ff erent combinations of battery technologies—lithium-titanate (LTO)-lithium nickel-ithium-iron phosphate (LFP) and cobalt-manganese (NMC)—charging infrastructure and well-to-tank pathways. Results show that scenarios including electric technologies mitigate the GHG emissions by 58–10% compared to the baseline diesel bus, although their high life cycle costs, ranging from 129–247%. LTO systems are the most e ff ective batteries for the mitigation of GHG emissions. Electric vehicles are investigated also in previous SDEWES SIs: (i) Vialetto et al. [ 36 ] performed a thermodynamic study of a shared cogeneration system for Northern Europe climate; (ii) Del Moretto et al. [ 37 ] compared diesel and electric tourist trains from environmental, energy and socio-economic points of view in 4 Energies 2019 , 12 , 3150 a novel sustainable mobility connection for campsites; (iii) Novosel et al. [ 38 ] modelled the energy planning of the Croatian transportation system; (iv) Firak et al. [ 39 ] investigated the Croatian future transportation sector based on hydrogen infrastructure and fuel-cell vehicles; (v) Briggs et al. [ 40 ] analysed and simulated an inner-city diesel-electric hybrid bus; and (vi) Knez et al. [ 41 ] considered policies for the commercialization of low emission electric vehicles. Numerous papers dealing with energy e ffi ciency in urban areas were involved in SDEWES SIs [ 42 ], specifically focusing the trends of European research on district heating and cooling networks [ 43 ] and the energy management in municipalities [ 44 ]. In this framework, a comprehensive benchmarking of sustainability of urban energy, water and environment systems investigating 120 cities is performed by Kılkı ̧ s [ 17 ] by the definition of the Sustainable Development of Energy, Water and Environment Systems city index (SDEWES Index [ 18 ]). The index, considered a useful benchmarking tool, aims at comparing the cities sustainable performance, and includes seven dimensions: (i) renewable energy potential and utilisation, (ii) penetration of energy and CO 2 saving measures, (iii) CO 2 emissions and industrial profile, (iv) water and environmental quality, (v) research and development, innovation and sustainability policy, (vi) city planning and social welfare and (vii) energy consumption and climate. By proposing a scenario where the use of residual energy among near cities, improvements of the index indicators on 60 cities are detected. The benchmarking results can be used by urban planners and local decision-makers to motivate policy-learning opportunities. A similar work is presented also in [ 19 ], where the SDEWES Index is calculated for 26 significantly di ff erent cities from around the world, from Europe, Latin America and Africa as well as new cities in Asia. The higher values of the index are detected for cities including e ff ective urban management in environment and water and e ffi cient district energy networks. Copenhagen obtains the highest value of the index. A multi-criteria decision-making technique is implemented by Carli et al. [ 20 ] in order to evaluate the sustainability of metropolitan areas by considering their energy, water and environment systems. In this work, the authors aim to demonstrate the novelty and robustness of their approach, based on analytic hierarchy process with respect to the well-established method, such as the above mentioned SDEWES Index. This work covers the research gap concerning the assessment of the sustainability of metropolitan cities and provides their specific improvements, by means of the estimation of qualitative indicators. Their approach, applied to the four metropolitan areas Bitonto, Bari, Molfetta and Mola in South Italy, show the strategic and overriding interventions to obtain sustainable metropolitan cities. The limitation of the proposed approach is due to the vagueness and genuine uncertainty typical of the human decision making. The role of the