Assessment of the progress towards the establishment of definitions of Nearly Zero Energy Buildings (nZEBs) in European Member States

Abstract The European Climate and Energy package foresees a substantial reduction of energy consumptions in buildings by 2020. The implementation of Nearly Zero Energy Buildings (nZEBs) as the building target from 2018 onwards represents one of the biggest challenges to increase energy savings and minimize greenhouse gas emissions. The aim of this paper is to provide an overview of the European status towards the implementation of nZEBs. The main open issues are presented together with categories, definitions, and calculation methodologies. The paper reports the progress made by Member States (MS) towards the adoption of nZEBs definitions through the analysis of the available literature, National Plans, templates submitted to the Commission, as well as information from the EPBD Concerted Action (CA) and Energy Efficiency Action Plans (NEEAP). Different aspects to be outlined, such as balance, boundary, energy uses, and renewables are taken into account in the study. Results show that progress is evident in many MS compared to first attempts to launch a national definition, but coherency cannot yet be found. The current situation is discussed to contribute to the clarification and the establishment of agreed definitions. The paper underlines the effort to integrate the nZEBs notion into National Codes and International Standards. It also shows how this topic has gained a growing attention in the last decade, but the achievement of a common nZEBs concept is still far to be reached and implemented into construction practices and routines, especially at a refurbished level.