This paper presents the editorial for the Renewable and Sustainable Energy Reviews joint special issue devoted to the research work discussed and presented at the 11th Conference on Sustainable Development of Energy, Water and Environment Systems (SDEWES), held from the 4th September to the 9th September 2016 in Lisbon, Portugal and the 2nd South East European (SEE) SDEWES Conference held from June 15th to June 18th, 2016 in Piran, Slovenia. This special issue is in line with the journal's aim of publishing research from across the ever-broadening field of renewable and sustainable energy with a strong review element. Previous SDEWES conference special issues have gathered a significant knowledge base in the field of sustainable development that reflects the continuous research efforts of the SDEWES research community. Therefore, this editorial provides not only an overview of the papers published in this particular special issue, but also a wider overview of the current trends in the domain of sustainable and renewable energy. This year's special issue focuses particularly on the benefits of the bio-based economy, energy security issues, fossil fuel thermal plant alternatives and environmental constraints, district heating and cooling together with cross sector energy efficiency and energy conservation issues. Sustainable transport systems, the issue of fuel poverty in urban neighbourhoods and renewable energy to support development of peripheral rural areas, optimising passive building design for hot climates and solar-powered heating and cooling are further topics featured in this special issue. In the process of selecting papers for this special issue, the guest editors invited in total 23 extended manuscripts for consideration for publication. After a rigorous review process by expert reviewers overseen by the guest editors a total of 16 articles were accepted for publication.