Innovative glazing systems composed of photovoltaic cells and monolithic aerogel layers: Electrical and thermal experimental characterization and simulation analysis

Building-Integrated Photovoltaic (BIPV) solutions enable full utilization of a building envelope for clean electricity generation. This study investigates an innovative photovoltaic (PV) glazing system capable of producing energy that addresses the thermal weaknesses of windows through the use of an integrated silica aerogel layer (translucent material with low thermal conductivity). The performance was evaluated for three types of PV cells. For each of these cells, I-V and P-V curves were constructed from experimental data taken from the cells with and without the aerogel layer. Numerical simulations were used to assess the electrical productivity and the surface temperatures under different climate conditions. Results show that the aerogel layer slightly decreases the cell peak power (by 7.0% for a bifacial monocrystalline cell) for perpendicular irradiation, with a more significant decrease (up to 30%) when solar radiation is not perpendicular to the panel. For this reason, cold climates with short daylight hours could most benefit from this solution. Bifacial cells showed the best performance, with only a 7–8% decrease in energy production, compared to polycrystalline cells, with a decrease of 18–22%. Although the peak power of the cells is slightly reduced, the presence of aerogel contributes to a 4–7°C reduction in the average surface temperature. In Mediterranean and continental climatic conditions, the total annual number of hours with temperatures higher than 40°C is reduced by 60–74%. The effect of the aerogel is also more pronounced in the northern regions.