A recent research indicates that federal reservoirs might significantly contribute to meeting the solar energy demands of the country, as outlined in Solar Energy.
This study, conducted by geospatial experts Evan Rosenlieb and Marie Rivers, along with Aaron Levine, a senior legal and regulatory analyst at the U.S. Department of Energy National Renewable Energy Laboratory (NREL), provides the first-ever estimate of energy generation potential from floating solar installations on federally managed reservoirs. Developers can find detailed information about each reservoir on the AquaPV website.
The solar energy production potential is substantial: these bodies of water could support floating solar installations capable of generating around 1,476 terawatt hours each year—enough to supply power for about 100 million households.
“That showcases the maximum energy potential,” Rosenlieb noted, mentioning the output that would be achievable if all reservoirs were outfitted with the highest feasible number of floating solar panels. “While we acknowledge that not all this potential will be tapped, even attaining just 10% of our projections could lead to a significant impact.”
As of now, Levine and Rosenlieb haven’t evaluated how human activities and wildlife might influence the deployment of floating solar projects at specific reservoir sites, but they plan to investigate this further in their upcoming studies.
This research provides more accurate insights regarding the feasibility of floating solar energy in the U.S., which may aid developers in strategizing projects on federal reservoirs and assist researchers in assessing the integration of these technologies into national energy frameworks.
Floating solar panels, commonly known as floating PV, offer multiple benefits: they generate electricity without occupying valuable land and also provide shade over the water bodies, which helps to minimize evaporation and preserve critical water resources.
“However, we have not yet witnessed any large-scale implementations, particularly at major reservoirs,” Levine highlighted. “In fact, there are currently no U.S. projects exceeding 10 megawatts.”
While past research has attempted to estimate solar energy potential from floating installations, Levine and Rosenlieb are the first to pinpoint which water sources provide optimal conditions for such energy solutions.
For instance, in some reservoirs, shipping activities can generate waves that may harm mooring systems or disrupt the floating infrastructure. Other areas might be too cold, shallow, or have steep banks, making it challenging to securely install solar panels.
Nonetheless, certain hydropower reservoirs might be particularly suitable for floating solar energy systems. Merging solar power with hydropower can enhance energy supply reliability and resilience. For instance, during a drought, even if water levels drop at a hydropower reservoir, solar panels could continue to generate electricity while waiting for water levels to restore.
Moreover, when establishing new pumped storage hydropower projects—where water is moved to a higher reservoir for storage—developers frequently create new, isolated water bodies that are not connected to flowing rivers and currently do not serve any immediate human or wildlife needs.
Looking forward, the researchers plan to examine potential sites based on their proximity to transmission infrastructure, electricity demand, anticipated development expenses, environmental protection requirements, and strategies for navigating applicable state and federal regulations. They also aim to investigate additional locations including smaller reservoirs, estuaries, and possibly offshore regions.
This research received support from the Solar Energy Technologies Office and the Water Power Technologies Office under the DOE’s Office of Energy Efficiency and Renewable Energy (EERE).
