The impact of natural ventilation on building energy requirement at inter-building scale

Abstract

Inter-building effect is responsible for affecting buildings’ primary energy requirement for heating, cooling, and lighting. Nevertheless, the impact of natural ventilation should also be considered while predicting building energy demand, since it is documented to substantially affect indoor environmental quality and thermal comfort. This paper investigates the impact of natural ventilation on building primary energy requirement prediction. The Inter-Building Effect (IBE) approach is applied in a typical residential block in Italy. A sensitivity analysis is performed to determine the key input parameter among (i) climate boundary, (ii) infiltration rate, (iii) opening percentage, and (iv) wind strength. Two scenarios, i.e. the stand-alone building and the same building surrounded by its neighborhood, are compared. The thermal-energy dynamic simulation of the different scenarios is carried out to investigate the impact of outdoor airflows on building primary energy requirement for heating and cooling and on indoor thermal comfort, investigated by means of the Thermal Deviation Index method. Inaccuracies in energy need prediction imputable to natural ventilation without taking into account the IBE are detected. The findings show that IBE is much more affected by buildings’ opening percentage, infiltration rate, and local wind compared to the weather context since IBE is a local microscale phenomenon.