A study published in Solar Energy by a team led by researchers from the National Renewable Energy Laboratory determined that the number of floating solar panels on federally owned reservoirs around the nation can keep 100 million homes yearly. In aid of renewable energy planning, these researchers mapped out the potential by applying highly developed geospatial criteria.
Unlocking the Power of Water
Researchers leading the effort, geospatial scientists Evan Rosenlieb and Marie Rivers, estimated that reservoirs could support upwards of 77,000 megawatts of floating solar capacity with the help of a senior legal analyst, Aaron Levine. If deployed, this can yield 1,476 terawatt-hours annually-equivalent to powering one out of every three U.S. households.
This is the technical potential,” Rosenlieb said. “While it is unrealistic that every reservoir can be fully harnessed, tapping just 10% of this potential would go a long way toward the renewable energy targets.
Floating solar panels offer several advantages, also titled as photovoltaic systems, which are that in making use of water surfaces, the systems do not compete with agricultural or urban uses. The panels contribute to resource savings by reducing water evaporation and keeping water temperature relatively cooler.
Challenges and Next Steps
While the study does offer some promising data, the researchers are quick to list several challenges that exist. “Reservoir conditions-water depth and temperature, but also human use, such as shipping traffic-can limit development in certain areas. Concerns about impacts to local wildlife and recreation will have to be borne with care.”.
Levine highlighted the lack of large-scale installations in the U.S., with no single project exceeding 10 megawatts. “Other countries have embraced floating solar, but we’re still in the early stages here. This research aims to provide a roadmap for scaling up.”
A Hybrid Future
One of the most intriguing prospects involves the marriage of floating solar with conventional hydropower. In these hybrid systems, for instance, panels could supplement the supply when drought or other low-water conditions lower hydropower production to maintain the same level of power production more consistently.
“These combinations could strengthen grid resilience and reliability,” said Rosenlieb. “Hydropower and solar are a natural fit. This synergy presents new opportunities.”
Looking Ahead
The NREL team says that it will flesh out its analysis with additional determinants, like proximity to transmission lines, development costs and regulatory hurdles. The team also aims to evaluate other potential sites, including smaller reservoirs, estuaries and offshore sites.
The research, led by the Department of Energy’s Solar Energy and Water Power Technologies Offices, has also resulted in the development of AquaPV: an openly available tool providing detailed information for specific reservoirs.
Bright Future for Floating Solar
As the U.S. continues to develop its renewable energy, floating solar panels may become imperative. With innovative tools like AquaPV and an ever-improving understanding of technical feasibility, the potential impact of floating solar on the energy landscape is immense.
