Giuseppe Pio Costa

Photovoltaic farms in peri-urban and rural areas are spreading all around the world. The presence of photovoltaic panels can cause several effects on the environment matrixes (i.e., soil, water, air, vegetation), mainly due to the shield-like effect that panels exert against both sunrays and rainfall. Often, such installations produce a decrease in the soil temperature and potential evapotranspiration, whereas an increase can be observed in the soil moisture, bringing to better growing conditions for the vegetation, especially in arid climate areas. Moreover, panels induce a spatiotemporal redistribution of the rainfall, which can lead to a less homogeneous distribution of the rainfall on the ground, and to the reduction of distributed erosion and sealing of the soil at the plant scale. Right now, it is not well understood whether the panels cause modification of flood propagation and, thus, a greater hazard downstream the installation area, as well as whether their presence imply more localised erosion below the panel lowest boarder.

Ongoing research aims to develop a comprehensive methodology able to address the best design practices, including eventual mitigation measures, that ensure the hydraulic compatibility between photovoltaic plants and both runoff waters and the local hydraulic network, meeting all the regulation constraints in the meantime.

Coupling numerical models with field measurements, more reliable models can be created. These can be useful to analyse and compare different solutions to mitigate hydraulic related impacts. To this aim, a huge catalogue of case studies in Sicily is considered, in which different slope, soil type, land use, and other environmental conditions are investigated.

The main expected outcome of the present research is to make the design process of hydraulic impact mitigation interventions more reliable, reducing at the same time the impact on the environment due to photovoltaic installations.