Abstract
Ensuring an appropriate ventilation rate and a suitable indoor air quality is a major energy consumption driver particularly in high performance buildings. Heat recovery devices coupled with mechanical ventilation systems can help saving energy. In the design or operating phases their contribution is typically estimated in terms of nominal effectiveness. However, operating conditions and eventually contro l strategy can strongly affect the heat recovery performance. In this work, the potential energy savings of sensible and total heat recovery devices is analyzed. Starting from hourly weather data, the impact of indoor conditions on the sensible and latent recovery is analyzed, defining appropriate control strategies to prevent recovery when dehumidification by cooling would then be required. Sensible heat recovery systems have been compared with enthalpy wheels. By means of a parameterization of the operating constraints and the expression of the main quantities in specific terms, only as a function of the building use, it has been possible to generalize the main results, and to compare different technologies and strategies in a comprehensive range of climatic contexts. Seasonal energy and economic performances have been quantified, providing a European map of the technical and economic performance of the considered technologies.