Assessing Nearly Zero Energy Buildings (NZEBs) development in Europe

Decarbonising the energy sector is crucial to reach future climate and energy goals. As established by the Energy Performance of Building Directive recast, Nearly Zero Energy Buildings (NZEBs) are the mandatory building target in Europe for all new buildings from 2021 onwards. In the light of the approaching deadline, this paper assesses the development of NZEBs in Europe based on the most recent collected data and information. This paper provides an overview of the implementation of national definitions and energy performance values for new, existing, residential, and non-residential buildings in Member States. It evaluates the differences with the established European benchmark and cost-optimal levels. An overview of the most commonly implemented technologies in NZEBs is given together with costs and the relative projections over next decades. Finally, quantitative data on the NZEBs diffusion in Member States are given as recently assessed. The evolution of the NZEB concept and the future NZEBs role is also forecasted. The results assume a strategic value in the light of future targets for the building sector, showing the progress made by Member States in relation to different NZEBs aspects. They provide a comprehensive analysis of the European NZEBs implementation depicting a positive overall progress improvement for NZEBs definitions, uptake, technology development, and energy performance levels. Next challenges and barriers are outlined and appear mainly related to NZEBs retrofit.