Floating photovoltaics, a new frontier

Our quest for increasingly advanced solutions to produce renewable and sustainable energy has reached a new frontier: that of the hybridization of hydropower and solar energy. The project was developed back in 2020 at our Innovation Lab in Catania, thanks to our collaboration with NRG, and then adopted at the Venaus power plant in Piedmont.

Venaus is in the Susa Valley, not far from the French border: here Enel Green Power has built the first floating photovoltaic plant, using part of a large service reservoir at a hydroelectric power plant that has been in operation since the late 1960s. 

This is what is called hybridization between solar and hydro, a solution that offers advantages for both technologies. Compared to a classic photovoltaic plant, the efficiency of solar panels improves due to the relatively low temperatures, on account of the proximity of the water on which they float: as the temperature increases, the solar panels gradually become less efficient. The water the panels float on can be used for their cleaning, thus saving on water resources; and the presence of the plant also acts in turn as a “screen” for heat, thereby limiting evaporation. Last but not least, this also reduces land consumption and there is no impact on the landscape, because the photovoltaic plant floats on an artificial reservoir, as opposed to a lake. 

The hybridization of the plant also enables more accurate remote monitoring, thanks to the SCADA (Supervisory Control And Data Acquisition) system. This is normally adopted for photovoltaic systems and is now integrated with the hydropower plant, thus enabling real-time monitoring of the status and performance of the various components.

With a capacity of about 1 MW and an expected annual output of about 1,200 MWh, the installation of new-generation photovoltaic modules manufactured by the Catania-based 3Sun factory takes advantage of the so-called “bifaciality” of the panels. They are equipped with solar cells that can absorb light on both sides, and thus capture direct and reflected solar radiation, thereby generating more electricity for the same amount of surface area occupied.

Catania is also the location of our Innovation Lab. Here, thanks to our collaboration with NRG, an Italian company specializing in energy efficiency, the process of hybridization was initially developed in 2020, with the installation of the first experimental floating platform, a small 30 kW “photovoltaic island.”

The success of the Venaus project is a significant example of our Group’s excellence and also of the role of “Made in Italy” in the field of renewable energy. The integration of solar and hydropower not only highlights our innovative and technological capacity, but also our commitment to pursuing sustainable and cutting-edge solutions. This floating plant shows how ingenuity and creativity can turn environmental challenges into opportunities, thus consolidating our role as a world leader in the renewable energy sector.