In the recast Energy Performance of Buildings Directive (EPBD) adopted in May 2010, a benchmarking mechanism for national energy performance requirements was introduced. The purpose of this is to determine cost-optimal levels to be used by Member States for comparing and setting these requirements. The previous EPBD (from 2002) set out a general framework to assess the energy performance of buildings and required Member States to define maximum values for energy delivered to meet the energy demand associated with the standardised use of the building. Cost optimal building performance requirements New eceee report on the calculation methodology for reporting on national energy performance requirements on the basis of cost optimality within the framework of the EPBD (2 May 2011).