Field optimization for bifacial modules

Bifacial modules are gaining more and more interest in PV market applications and strategies of major manu-facturers. The bifacial photovoltaic module is able to generate energy from both sides of the photovoltaic cell, thus increasing the energy production compared to a standard photovoltaic module. In order to obtain the maximum production from a bifacial panel, all the characteristics that influence its performance must be studied and optimized. The specific aim of this research work is the design of a bifacial photovoltaic field optimized for the exploitation of the albedo of the soil. The study for minimizing losses due to light reflection on the ground was conducted considering the following aspects: identification of suitable materials, optical simulations of possible configurations, field measurements on a small-scale system. To improve the RetroReflectivity (RR) of the ground the optimal RR material is the one with a diameter of microspheres of 200-300 mu m regardless of density. From the optical simulations the best configuration is a mixed ground with diffusive parts and a RR part. The results of the measurements show that once the ground is prepared in an appropriate way, we can have more than a 10% improvement in maximum power achieved and 2/3 of the light that hits the ground can be recovered.