A study of solar heat gain variation in building applied photovoltaic buildings and its impact on environment and indoor air quality

The solar heat gain is a significant factor to be considered while designing sustainable Heating Ventilation and Air-Conditioning system for the working rooms in the future. By installing photovoltaics on rooftop, building can be insulated from heat and the cooling load requirement for the rooms can be reduced significantly. Advantages of building applied photovoltaic systems for building insulation are justified by means of measurements and modeling. Thermal and air quality measurements outside and inside rooms of similar area, under different types of PV arrays are observed and the phenomenon of solar heat gain is studied. The experiment was conducted in Perundurai, Tamil Nadu, India, in the months of February and March of 2019. Thermal infrared imaging data for room ceilings showed a reduction of up to 2.5 degrees C under PV array compared to those with open roof. Computer simulations indicated significant differences in temperature, between ceilings covered by PV array and ceilings with open rooftop. The relative humidity inside the rooms covered by PV arrays is 10% higher as compared to rooms with open rooftop. Due to the installed 100 kW(e) solar photovoltaic plant, emission of nearly 100 kg CO2 is reduced per day. There is a reduction in 28.5% CO2 inside the room with elevated PV panels at the roof top compared to room without PV panels.