Mitigating water evaporation and enhancing renewable energy with floating photovoltaic systems: An integrated approach to resource sustainability

• The study assesses the impact of Floating Photovoltaic (FPV) technology on reducing water evaporation and generating renewable energy at five dams in the study area. • Climatic and hydrological data from 1994 to 2023 were analyzed using the FAO Penman-Monteith method for evaporation and the SPEI index for drought assessment. • The study explored FPV deployment at 5%, 10%, and 20% coverage, finding significant reductions in evaporation with 80% FPV efficiency. • the study evaluated the economic benefits, highlighting substantial reductions in CO 2 emissions and demonstrating the economic viability of FPV in enhancing water conservation and supporting sustainable energy solutions. Floating Photovoltaic (FPV) systems offer a new solution for managing water resources and producing sustainable energy. This study evaluates the impact of FPV technology on reducing water evaporation at five key dams supplying Tehran and nearby areas. Analysis of evaporation data and climatic conditions in the region from 1994 to 2023 showed that the cumulative evaporation during this period reached 2356.37 millimeters, and the SPEI index confirms a trend of increasing drought during this time. Using the FAO Penman-Monteith method, the 2023 evaporation rates were calculated, showing Taleghan Dam with the highest evaporation loss at 19,591,093 cubic meters and Mamlu Dam with the lowest at 7,117,110 cubic meters. The study explored FPV deployment at 5%, 10%, and 20% coverage for each dam. Estimates indicate that with 80 percent FPV efficiency, evaporation reduction could be significant, with Taleghan Dam’s losses decreasing to 16,456,518 cubic meters and Mamlu Dam’s losses decreasing to 5,978,372 cubic meters under 20 percent coverage. Furthermore, the potential for electricity generation was assessed, revealing that 10 percent FPV coverage of Latyan and Amir Kabir Dams could generate 72,064 MWh and 80,180 MWh of energy, respectively, while reducing CO 2 emissions by over 44,000 tons at each site. The economic analysis shows that FPV systems improve environmental sustainability by cutting evaporation and greenhouse gas emissions, while also supporting the economic feasibility of water and energy projects. This study underscores the importance of FPV technology in promoting integrated water conservation and renewable energy solutions amid climate change.