Evaluation of the potential energy recovery for ventilation air in dwellings in the South of Europe

Heat recovery in ventilation systems for dwellings in cold and mild climates is needed in order to meet the requirements of nearly zero-energy buildings (nZEB) in terms of energy demand. These requirements can be met without heat recovery systems in only a few European areas with warm climates. The energy recovery potential for warm Mediterranean cities located in the south of Europe has not been investigated in sufficient depth. This article proposes a new methodology to analyze the climate data using the psychrometric chart to determine in which cases it is of interest to recover heat only or to recover the latent energy. The study covers several cities in southern Europe and the results are compared with northern European cities in terms of recovery strategies. The result demonstrates the necessity to establish different energy recovery strategies in cities located in similar latitudes. The appropriate strategy can be established with the climate data analysis methodology proposed. In some cities, the convenience of recovering latent energy to meet nZEB energy requirements has been demonstrated.