Impacts of Fishing-Solar Complementary Photovoltaic Power Generation on Microclimate and Aquatic Ecosystems

The fishing-solar complementary (FSC) model, which integrates photovoltaic (PV) power generation with aquaculture, offers a promising approach for China to achieve its dual carbon goals while promoting sustainable fish farming. However, its environmental impacts remain underexplored. This study investigates the Liubao FSC PV station, a national “PV+” pilot project in the Gaoyou Lake area of the Huai River Basin. Combining field data with a water surface energy absorption model, we assess FSC effects on microclimate and aquatic ecology. Key findings include (a) the FSC system raised near-surface air temperature and relative humidity over fishponds by 0.89 ± 0.63 °C and 1.80 ± 2.11%, while reducing wind speed and solar radiation at the water surface by 1.75 ± 0.29 m·s −1 and 63.90 ± 97.19 W·m −2 ; (b) PV panel installation increased surface albedo, reducing net solar energy absorption by 105.76 ± 114.76 W·m −2 ; and (c) water temperature rose by 0.64 ± 0.08 and 0.40 ± 0.06 °C at depths of 0.25 and 0.5 m. Water quality improved, with dissolved oxygen up by 4.09 ± 1.10 mg·l −1 , pH by 0.64 ± 0.12, and chlorophyll a by 167.78 ± 42.95 μg·l −1 , while conductivity, turbidity, and oxidation–reduction potential decreased. The findings of this study provide important practical insights for establishing regional ecological impact assessment frameworks and promoting the coordinated development of the PV and aquaculture industries.