Review Addressing the main challenges of energy security in the twenty-first century e Contributions of the conferences on Sustainable Development of Energy, Water and Environment Systems Natasa Markovska a, * , Neven Dui  c b , Brian Vad Mathiesen c , Zvonimir Guzovi  c b , Antonio Piacentino d , Holger Schl € or e , Henrik Lund f a Research Center for Energy and Sustainable Development, Macedonian Academy of Sciences and Arts, Krste Misirkov 2, Skopje, Macedonia b Department of Energy, Power Engineering and Environment, Faculty of Mechanical Engineering and Naval Architecture, University of Zagreb, Ivana Lucica 5, 10002 Zagreb, Croatia c Department of Development and Planning, Aalborg University, A.C. Meyers Vænge 15, DK-2450 Copenhagen SV, Denmark d Department of Energy, Information Engineering and Mathematical Models, University of Palermo, Viale delle Scienze e Building 9, Palermo, Italy e Forschungszentrum Jülich, Institute of Energy and Climate Research (IEK-STE), 52425 Jülich, Germany f Department of Development and Planning, Aalborg University, Skibbrogade 5, 9000 Aalborg, Denmark article info Article history: Received 27 September 2016 Received in revised form 19 October 2016 Accepted 20 October 2016 Available online xxx Keywords: Energy security Decrabonization Renewable energy sources Energy efficiency Smart energy systems SDEWES abstract Climate change and fossil fuel reserve depletion both pose challenges for energy security and for well- being in general. The top ten among them include: Decarbonising the world economy; Enhancing the energy efficiency and energy savings in buildings; Advancing the energy technologies; Moving towards energy systems based on variable renewables; Electrifying the transport and some industrial processes; Liberalizing and extending the energy markets; Integrating energy sectors to Smart Energy Systems; Making the cities and communities smart; Diversifying the energy sources; and Building more bio- refineries. Presenting the contributions of selected conference papers published in the special issues of leading scientific journals (including all the papers from the current Energy special issue), this review demonstrates the capacity of the Conferences on Sustainable Development of Energy, Water and Envi- ronment Systems for generation of knowledge which could serve as the centrepiece of a pertinent response to those challenges. © 2016 Elsevier Ltd. All rights reserved. Contents 1. Introduction ....................................................................................................................... 00 2. Review ............................................................................................................................ 00 2.1. Decarbonising the world economy ............................................................................................. 00 2.2. Enhancing the energy efficiency and energy savings in buildings ................................... .............................. 00 2.3. Advancing the energy technologies .................................................. .......................................... 00 2.4. Moving towards energy systems based on variable renewables .................................... ............................... 00 2.5. Electrifying the transport and some industrial processes .......................................................................... 00 2.6. Liberalizing and extending the energy markets .................................................................................. 00 2.7. Making the energy smart ...................................................... .............................................. 00 2.8. Making the cities and communities smart ...................................................................................... 00 2.9. Diversifying the energy sources ............................................................................................... 00 * Corresponding author. E-mail addresses: natasa@manu.edu.mk (N. Markovska), neven.duic@fsb.hr (N. Duic), bvm@plan.aau.dk (B.V. Mathiesen), zvonimir.guzovic@fsb.hr (Z. Guzovic), piacentino@dream.unipa.it (A. Piacentino), h.schloer@fz-juelich.de (H. Schl€ or), lund@plan.aau.dk (H. Lund). Contents lists available at ScienceDirect Energy journal homepage: www.elsevier.com/locate/energy http://dx.doi.org/10.1016/j.energy.2016.10.086 0360-5442/© 2016 Elsevier Ltd. All rights reserved. Energy xxx (2016) 1e9 Please cite this article in press as: Markovska N, et al., Addressing the main challenges of energy security in the twenty-first century e Contributions of the conferences on Sustainable Development of Energy, Water and Environment Systems, Energy (2016), http://dx.doi.org/ 10.1016/j.energy.2016.10.086