A new approach for the application of nearly zero energy concept at district level to reach EPBD recast requirements through a case study in Turkey

European Union Directive 2010/31/EU (EPBD Recast) has constituted the cost considerations into the energy performance calculations and put the Member States (MS) under the obligation that by the end of 2020, all new buildings should be designed and constructed as nearly zero energy buildings. On the other hand, reaching nearly zero energy level buildings and ensuring the decrease in carbon emissions may require high-cost measures, such as renewable energy systems. Even though the energy efficiency calculation method proposed by European Commission uses the 'global cost', high investment costs may cause a conflict in building construction phases. This paper focuses on the highest possible energy saving for building sector while considering the, global costs and market barriers caused by high investment costs and long payback periods. For this purpose, nearly zero energy level definition is suggested to be carried to the district level. It is proposed to analyze nearly zero energy levels firstly in buildings in the settlement and next in the district scale by implementing the further energy efficiency measures, such as the use of district heating/cooling systems and installation of renewable energy technologies in addition to the ones installed on-site. Financial benefits were also analyzed and compared, in terms of investment and global costs of nearly zero energy levels of buildings and districts. (C) 2017 Elsevier B.V. All rights reserved.