Energy performance analysis of tracking floating photovoltaic systems.

Floating photovoltaic systems (FPV) are an innovative technology, in which photovoltaic modules are installed on water surfaces with the aim of reducing land occupation and at the same time increasing its efficiency and creating synergies with aquaculture and hydroelectric plants. The purpose of this study is to evaluate the energy performance on an annual basis of a fixed G/FPV (ground/floating photovoltaic) system, with vertical, horizontal or two-axis tracking, with mono or bifacial modules. The simulated data for FPV (floating PV) systems are compared with those of a GPV (ground PV) system through performance indexes. The analysis of the energy output is carried out depending on the geometric variables of the plant. The energy production of PV systems is highly dependent on the local climate. Therefore, the study was developed for two locations characterised by different components of diffuse solar radiation, one at high latitudes and the other at mid-latitudes. The two locations are: Anapo Dam in Sicily (Italy) and Aar Dam in the Lahn-Dill district (Germany). As for the gain due to the bifaciality of the systems with bifacial modules, it can be stated that for the analyzed configurations, a gain greater than 3% can be obtained for Anapo Dam in Sicily and greater than 4% for Aar in Germany. As for the gain due to the natural cooling of the modules, it can be stated that for the analyzed configurations, a gain of more than 5% can be obtained for Anapo Dam in Italy and greater than 4% for Aar in Germany. If the overall gain due to bifaciality tracking and cooling is considered, the following gains are obtained for the two locations Anapo and Aar respectively: 16.9% and 14.4% for Horizontal E-W system; 27.6% and 23.3% for Horizontal N-S system; 31.3% 27.8% for One Axis Vertical system; 47.4% and 42.5% for Dual axis system.