Abstract
Heat recovery ventilation (HRV) systems are increasingly recognized across Europe as a practical solution to enhance indoor air quality while reducing energy losses in residential buildings. They are frequently mandatory in contemporary building regulations and sustainability certification frameworks. In southern European contexts such as Spain, new housing developments often incorporate HRV systems, which are not explicitly required but might be required indirectly to comply with energy consumption limitations in building codes in the colder regions. The cost-effectiveness of these installations is strongly influenced by both local climate conditions and required ventilation rates. This research assesses the financial feasibility of mechanical heat recovery ventilation specifically in Spanish apartment buildings, accounting for the country’s varied climatic regions. Using regional climate data, the study calculates potential energy savings linked to HRV and compares them to baseline heating costs using a Levelized Cost of Energy (LCOE) approach, which incorporates initial installation expenses, recurring operating costs, and probable energy price fluctuations. The potential of demand-controlled ventilation is also addressed, in the form of humiditycontrolled ventilation. The findings suggest that HRV systems can be economically acceptable in Spain’s colder inland regions and in houses with more airflow demand, presenting acceptable LCOE and payback periods. However, in the more temperate coastal areas, these systems often fail to break even, highlighting the critical importance of climate-specific considerations. Beyond economic factors, this paper comments on other benefits of HRV, such as enhancing indoor thermal comfort in winter, filtration, and potentially lowering total energy demand. Future research should include thorough life-cycle cost evaluations.