Energy assessment of an autarkic building in Mediterranean climate

The development of energy efficiency strategies is strongly related to the results obtained by the research of low - energy buildings with high technological contents, that can allow a significant reduction of energy consumption and a simultaneous indoor comfort level increase. This work presents the energy performance analysis of an autarkic residential building, located in the suburb of L’Aquila, in central Italy. The analysis is performed via calibrated dynamic thermal model carried out with EnergyPlus engine coupled with DesignBuilder. The EnergyPlus model was calibrated by means of a statistical approach, on the basis of the actual thermal energy consumption of the heat generator. The aim of this study is to analyze if even an energy self-sufficient building can be subject to optimization margins. In fact, a significant difference between the high efficiency of the envelope, and the poor performance of the heating system was observed. Therefore, different possible scenarios were considered to assess the effects arising from different technological plants. The total thermal energy consumption of the heating system, as it is, is equal to 29.9 kWh/m2 y and substantial energy savings are obtainable by considering the different cases hypothesized in the multi-scenario analysis. Indeed, the best case allows energy savings up to 67.1% with respect to the original case. Moreover, different external climatic conditions were supposed, assuming that the building object of the analysis was located in three European capitals (Rome, Madrid, and London) characterized by different weather data. It can be concluded that a proper a-priori study of building’s thermal load, by considering different plant typologies, could help to choose the better solutions for realizing efficient buildings and that such solutions may differ according to the different external climatic conditions .