Integration of Phase Change Material into PV Windows to Improve the Efficiency of Semi-Transparent Panels Based on Luminescent Solar Concentrator Technology

This research addresses the need for enhanced thermal management in building-integrated photovoltaic systems, specifically focusing on semi-transparent PV panels based on luminescent solar concentrator (LSC) technology. In pursuit of optimal thermal regulation, the cooling effect of a paraffin PCM was investigated via finite element simulations developed with COMSOL Multiphysics. The PCM was thermally coupled with the PV cells situated in the frame of a south-facing window. Due to the seasonal difference between winter and summer, the PCM latent heat capacity and melting temperature were optimized to ensure the maximum nominal operating cell temperature (NOCT) reduction during summer months. PCM latent heat capacities equivalent to 120 kJ/kg, 180 kJ/kg, and 240 kJ/kg have been investigated, whereas for the melting temperature a range from 20 °C to 42 °C was spanned. The combination of higher latent heat and 36 °C melting point showed the most significant thermal benefits, by reducing the NOCT from 42 °C to 36 °C, which led to an 11.80% increase in power output across the whole PV window. Considering the same latent heat, the other melting temperature resulted in more moderate benefits, namely an enhancement of 7.88% and 3.94%, for 38 °C and 40 °C, respectively. The lower latent heat capacities resulted in an NOCT reduction that ranged between 2.7 °C and 5.3 °C, according to the associated melting point. These results testify that the presented solution could significantly enhance energy production in semi-transparent PV applications based on LSC panels.