Analysis of water environment on the performances of floating photovoltaic plants

There is an increasing interest in Floating PV (FPV) plants thanks to their advantages compared with ground and rooftop PV systems, mainly related to very limited land use, evaporation reduction, and improvement of the energy performance. The PV modules installed on water surfaces have a natural cooling due to the microclimate in which they operate, which reduces thermal power losses. Furthermore, they can be equipped with simple and effective forced active water cooling systems which further improve FPVs performance. The objective of this study is to develop and validate mathematical models capable of estimating the performance of bifacial and monofacial PV modules installed on water surfaces. Starting from the energy balances of the PV modules, different scenarios are simulated, such as mono and bifacial systems installed on the rooftop, mono, and bifacial FPV systems in presence of natural (or passive) and forced (or active) cooling. The models are validated against experimental data acquired in FPV systems installed in the Enel Innovation Lab by Enel Green Power, Catania (Italy). The obtained results show an energy gain due to bifaciality of 5.24%. The passive cooling in the FPV increases the energy collected by 3% (maximum obtainable of 6.4%) and 2.6% for the bifacial and monofacial technology respectively. Active cooling in FPVs increases the collected energy by 9.7% (maximum achievable of 13.5%) and 9.5% for the bifacial and monofacial respectively.