Effectiveness of energy performance certification for the existing housing stock

Abstract

The energy saving potential of the housing stock is considered to be large. Also this is considered to be the sector where energy efficiency measures can be pursued in the most cost effective way. In Europe the Energy Performance of Buildings Directive is a driving force for member states to develop and strengthen energy performance regulations for new buildings and set up a system of energy certificates for the existing stock and develop improvement policies based on these regulation tools. The goals are to build net zero energy buildings in 2020 and to reach a neutral energy situation in the whole stock by 2050. By now in the Netherlands a large share of the housing stock is labelled (Energy Performance Certificate). This paper is based on a research in which the indicated energy use according to the issued labels are compared to the actual energy use in the dwellings. The results point out that the influence of occupants on the actual energy use are large and potential savings might be (far) less in practice: in low labeled dwellings the energy use is less than expected, in the high labeled dwellings the energy use is somewhat higher than expected. What is the impact of these findings for the improvement policies of governments and housing associations?