In this work, a new solar system that includes photovoltaic-thermal (PVT) air collectors coupled to a water-to-air heat exchanger is investigated. The considered system generates sufficient energy for cooling and heating of the ambient air injected in a 300 m2 tertiary building and saves its total energy consumption. Therefore, it allows the minimization of greenhouse gas emissions of the building. A numerical model is developed to ensure comfortable temperatures during summer and winter, including days with the highest energy needs. The results show that the proposed system can generate the required heating and cooling needs using an airflow rate equal to 0.25 kg/s and a PVT area of 17 m2. It was found that the coupling of the PVT air collectors with a water to air heat exchanger minimizes the total required area for heating by ~ 33%. Moreover, the PV module's efficiency was enhanced by 2.0% in winter and 5.1% in summer. The thermal energy saved for heating, thermal energy saved for cooling and the electrical energy saved are, respectively, equal to 15.30 kWh/day, 24.79 kWh/day, and 3.14 kWh/day. This represents an average emission reduction of 11.4 kg CO2 per day.
Keywords: Energy saving; Greenhouse gas emissions; Photovoltaic air collectors; Renewable energies; Thermal comfort in buildings; Water to air heat exchanger.