All-air system for heating and cooling in residential buildings: a simulation-based analysis

Energy saving and CO2 emissions are a pivotal environmental priority of the last decades. The buildings sector is responsible for about 40% of total energy consumption. Some of the open options to decrease this value are improving the quality of building envelope and using energy-efficient heating and cooling technologies, also based on renewable energies. On the other hand, HVAC systems should provide high indoor air quality for the users as well as the control of heat and latent gains. In this work, an all-air system for both heating and cooling of residential dwellings is investigated. The all-air system was modelled through the software TRNSYS, simulating the building and the plant at the same time. To consider the effect of the weather, annual simulations were carried out in three different locations: Helsinki, Milan and Rome. Moreover, the all-air system was compared with a radiant floor system in the same conditions. The results outline as the proposed all-air system is an interesting solution when the building envelope is optimized to control the heat losses and the solar gains.