High frequency monitoring for impact assessment of temperature, oxygen and radiation in floating photovoltaic system.

Floating photovoltaic (FPV) systems are designed for free water surface installations to provide a feasible solution for places with no availability of land areas and to avoid land-use conflicts caused by conventional solar energy farms. However, lakes and reservoirs are essential for ecosystem services like water supply and biodiversity support. In this regard, there was a lack of long-term and high-frequency monitoring data of important parameters influenced by FPV installation such as photosynthetically active radiation (PAR) and dissolved oxygen (DO). Temperature, despite being more reported, there is no consensus on increase or decrease values below the FPV. In this study, we conduct a comprehensive field assessment to accurately quantify temperature variations (at the weather station, modules, between the modules and the water surface and within the water), DO, and PAR of a FPV installed in a water supply reservoir. High-frequency monitoring sensors indicated that despite the 94.7% of radiation reduction below the FPV compared to the lake reference station, slight differences in water temperature and dissolved oxygen were found between measurements in monthly and daily averages in a system that covers less than 1% of the reservoir water surface. In addition, a microclimate due to the module warming is created between the module and water surface with temperature 12% greater than the weather station measurements. The fluctuation throughout the different time frequencies showed that the processes of the reservoirs are influenced by the FPV according to complex interactions among meteorological conditions, FPV configuration, and site-specific factors.