By Abbas Nazil
A new study by Oregon State University and the U.S. Geological Survey shows that floating solar panel systems offer significant clean-energy potential but can affect aquatic ecosystems in ways that vary widely depending on the reservoir in which they are installed.
Researchers modeled the deployment of floating photovoltaic systems on 11 reservoirs in six U.S. states and found that while the panels consistently cooled surface waters and altered temperature layers, they also created increased variability in habitat suitability for aquatic species.
Lead author Evan Bredeweg explained that reservoir depth, circulation, and key fish species all influence how these systems impact local ecology, making it clear that no universal design approach exists for floating solar development.
Interest in floating solar is growing in the United States, though adoption remains limited compared with Asia. A recent U.S. Department of Energy assessment estimated that American reservoirs could produce up to 1,476 terawatt-hours of electricity each year through floating solar, enough to power around 100 million homes.
Floating solar technology offers multiple benefits, including improved panel efficiency from water-based cooling, potential reductions in evaporation, and the ability to integrate with existing hydropower and transmission infrastructure.
However, the environmental implications are still not fully understood. Bredeweg emphasized that assessing ecological risks is essential to ensure floating solar supports clean-energy goals without harming freshwater ecosystems.
The study examined summer and winter conditions and found that temperature and oxygen shifts influence habitat availability for both warm-water and cold-water fish.
Cooler summer temperatures tended to favor cold-water species, especially when more than half of a reservoir’s surface was covered by panels.
Researchers stressed the need for continued study and long-term monitoring, noting historical examples where large-scale modifications to freshwater systems—such as hydroelectric dam construction—produced unforeseen consequences.
Co-authors from Oregon State University and the U.S. Geological Survey contributed expertise in fisheries, conservation science, marine ecology, and freshwater research to the project.