Demand vs consumption Analysing the energy certification for buildings

Abstract

The directive 200291EC of the European Parliament and the Council of 16th December, 2002 (Energy Performance of Buildings Directive, EPBD, 2002) requires member states to introduce an energy certification in order to reduce energy consumption in buildings. For the appraisal of the energy, key-figure paragraph 2 of the directive generally allows both the theoretical calculation of energy demand and the collection of the real energy consumption; however, these two approaches do not always lead to the same result, but rather to substantially different values. Naturally, this leads to lively discussions among the involved persons. This paper is the first survey of a study whose goal is to explain where the differences between the two approaches arise from. The first results, for example, show that external walls, ceilings and roofs with a theoretically poor thermal quality are expected not to be as bad in practice as the theoretical calculation would lead us to believe. © 2007 PALGRAVE MACMILLAN LTD.