Sustainability trade-offs across modeled floating-solar waterscapes

Expansion of floating photovoltaic (FPV) solar energy on water could provide a low-conflict renewable energy option to help mitigate climate change while sparing land, but potential sustainability trade-offs of FPV siting have not been quantified. We compared technical potential of maximum, utility-scale (≥1 MW) FPV deployment to address the climate crisis with FPV buildout scenarios that prioritize biodiversity and social benefit across a waterscape. Maximum FPV buildout in the northeastern United States could provide nearly a quarter of regional solar energy generation and offset all the land needed for utility-scale, terrestrial solar by 2050, but trade-offs, including maintenance of freshwater biodiversity in lakes and ponds and social values, exist. Avoidance of socioenvironmental interactions yields an FPV-energy generation potential equal to a 5% increase in regional solar energy generation, but possibilities for co-location make this a conservative estimate. Consideration of trade-offs can guide siting of FPV to achieve multiple sustainability goals.