The study, published in the journal Solar Energy, represents the first comprehensive assessment using advanced geospatial analysis to determine exactly where floating solar installations could be viable on federally managed waterways. Rather than relying on broad assumptions, researchers developed novel methods to evaluate specific site conditions including water depth, temperature, and current patterns.
Beyond Simple Estimates
“Even in our most conservative scenario, the estimated potential for floating photovoltaics is more than half the PV capacity estimated to be required for a decarbonized U.S. electricity grid in 2050,” the researchers note in their findings. This conservative estimate amounts to 861 gigawatts of potential capacity.
The analysis reveals surprising variability in how much of each reservoir could potentially host floating solar installations. While previous studies typically assumed a flat percentage of reservoir area would be suitable, the new research shows developable areas can range from as little as 2% to as much as 81% of a reservoir’s surface, depending on specific site conditions.
Regional Distribution
The potential for floating solar development isn’t confined to any single region. However, the largest opportunities are concentrated in three states: Texas leads with 137 gigawatts of potential capacity, followed by California with 102 gigawatts and Oklahoma with 84 gigawatts. These three states alone could host nearly 40% of the nation’s total floating solar potential on federal reservoirs.
Technical Innovations
To determine viable installation areas, the researchers developed sophisticated criteria accounting for multiple factors that could impact floating solar development. Key considerations included:
- Water depth requirements of at least 1 meter to support the floating infrastructure
- Surface current limitations of 2 meters per second to prevent stress on mooring systems
- Temperature thresholds to avoid areas prone to ice floes that could damage installations
- Bottom slope requirements to ensure stable anchoring
Practical Limitations
The researchers emphasize that their findings represent technical potential rather than what might actually be built. The study specifically focused on technical feasibility without considering other crucial factors such as environmental impact, regulatory requirements, or economic viability.
Of the 846 reservoirs analyzed, 85 were found to have no viable potential for floating solar development due to technical limitations. Among those with development potential, system sizes varied dramatically—from small installations of just 10 kilowatts to massive potential facilities of up to 76.6 gigawatts.
Future Implications
The research opens new pathways for renewable energy development that doesn’t compete for limited land resources. Floating solar installations could offer additional benefits beyond power generation, including reduced water evaporation through surface shading and potential synergies with existing hydropower infrastructure.
As the United States pushes toward ambitious clean energy goals, this research provides crucial data for policymakers and developers to identify the most promising sites for floating solar deployment. The findings suggest that federal reservoirs could play a pivotal role in the nation’s renewable energy future, though realizing this potential will require careful consideration of environmental impacts and regulatory frameworks.
The study was conducted by researchers from the Department of Energy’s National Renewable Energy Laboratory and published in the journal Solar Energy.
