Solar panels on bodies of water in the northeastern U.S. might generate renewable energy but could also carry risks for birds, especially waterbirds. Now a new study provides a data-informed approach to siting floating solar that could protect waterbirds and others, without sacrificing the potential for energy generation.
In the study, published Dec. 23 in Environmental Science & Technology, researchers used data from a previous Cornell-led project that assessed the energy potential of lakes and ponds in the Northeast, finding more than 16,000 suitable locations based on size and proximity to infrastructure. They overlaid that map with a map of bird abundances from the Cornell Lab of Ornithology's eBird Status and Trends tool.
Using the datasets, they were able to identify bodies of water with the highest likelihood of potential interaction between floating solar facilities and birds, finding that high energy potential didn't often overlap with high bird interaction.
"Based on our findings, it could be possible to reduce risk to birds via ecologically informed siting, and that might not instill a reduction in energy production," said Steven Grodsky, assistant professor of natural resources and the environment in the College of Agriculture and Life Sciences (CALS). "This study is the best available science to understand potential interactions, and it can point us towards areas of synergy or conflict, areas where we might want to focus for field studies or conservation."
With the Lab of Ornithology data, the researchers also drilled down on morphological traits, conservation status and habitat requirements of 291 bird species to determine species that might be most vulnerable in a given area, which could be a "real boon" for wildlife management, Grodsky said. The horned grebe, for example, is decreasing in population already and has low maneuverability and vision, which could make interactions with solar panels more treacherous.
Researchers - including first author Alison Binley, former Edward W. Rose Postdoctoral Fellow at the Lab of Ornithology - also assessed the risks the birds might pose to panels. A gaggle of Canadian geese, for example, might defecate so much on the panels that energy production would be compromised - an incentive for industry to avoid bodies of water with a high abundance of birds. Lakes and ponds with high avian biodiversity were also correlated with higher recreational value, so avoiding them could avert disruption of activities like boating and birdwatching, as well as pushback from residents.
"We're trying to look at it holistically, to understand how floating solar can affect birds, how birds can affect floating solar," said Grodsky, who is also assistant unit leader of the U.S. Geological Survey New York Cooperative Fish and Wildlife Research Unit housed in CALS and a faculty fellow at the Cornell Atkinson Center for Sustainability. "The overarching goal is to operationalize sustainability outcomes and an ecologically informed energy transition."
The study focused on the northeastern U.S. - stretching from New England and New York to Virginia and Washington, D.C. - which constitutes a significant portion of the Atlantic flyway and where an abundance of water and above-average energy needs make floating solar an attractive option.
But within the results was also a note of caution: Currently, floating solar in the U.S. has largely been deployed on ponds or smaller lakes, and the researchers found that smaller bodies of water, especially in the Great Lakes and coastal areas, are at highest risk of interactions with birds. Grodsky said the research provides an opportunity to get ahead of potential conflicts.
"With terrestrial solar, buildout is well underway, but floating solar is a relatively nascent technology, and there's opportunity to inform siting with biodiversity, social values, energy production in mind - all of these components that are connected," Grodsky said.
The study provides a framework to assess birds' interactions with solar installations more broadly; in the near term, Grodsky and his team plan to use the approach to map potential bird interactions with land-based solar in New York state. Grodsky also hopes the study will identify locations for field studies as floating solar emerges in the Northeast.
"From here, we can implement field studies and target particular species for study in the region," Grodsky said. "Then with those pieces of the puzzle in place, we can better contextualize the tradeoffs and make more informed decisions about siting, management and sustainable development."
Co-authors of the study include Amanda Rodewald, Garvin Professor, senior director of the Lab of Ornithology's Center for Avian Population Studies and faculty director at Cornell Atkinson; and former postdoctoral researcher Adam Gallaher.
Funding from the study was provided by the Cornell Lab of Ornithology and Cornell Atkinson.
