Study: Floating Solar Panels on Reservoirs Show Great Potential

Solar is a rising source of clean, reliable energy, but there has been some opposition to its growth because large-scale photovoltaic installations require large amounts of land. One possible solution is what is known as “floatovoltaics,” or floating solar panels. These panels, anchored with buoys, can be deployed on bodies of water.

A recent study, conducted by the U.S.  Department of Energy’s National Renewable Energy Laboratory (NREL) looked at the potential of federal reservoirs throughout the country to contribute to meeting U.S. energy needs. The study concluded that floating solar panels on these water bodies have the potential to “generate up to 1,476 terawatt hours, or enough energy to power approximately 100 million homes a year,”  a release states.

This “technical potential” considers that each suitable reservoir has the maximum number of panels possible. While the study authors recognize that scale is highly unlikely, using just a portion of these reservoirs would generate a lot of power. “Even in the most conservative scenario considered for this subset of federally owned and regulated reservoirs, the estimated potential for FPV (floating photovoltaic panels) is more than half the PV capacity estimated to be required for a decarbonized U.S. electricity grid in 2050,” the study states.

One important note is that there are many other reservoirs and bodies of water across the country, however only federal reservoirs were included in the study. The authors were also able to develop more accurate data about which reservoirs might be suitable for solar development.

A number of reservoirs were identified as being unsuitable due to cold-weather locations, size, lack of depth, or sloping bottoms that would prevent mooring buoys. The study also excluded reservoirs that are used for shipping, so the solar panels would not be in the way of important routes.

One issue that has yet to be addressed is the possible impact of floating solar panels on human and wildlife activities. Solar panels would shade and cool bodies of water, but the effects of that must be studied. Also yet to be considered is the effect of solar installations on recreational use of these reservoirs. However, NREL plans to address this in future studies.

Another major upside to implementing floating solar panels is that they can readily be combined with hydropower generation. Hydropower “uses the natural flow of moving water to generate electricity” and a number of federal reservoirs are hydropower dam projects, which already have transmission infrastructure. Co-location of these projects could yield more energy throughout the entire year, especially during droughts that make hydropower less effective in producing energy.

Overall, floating solar panels show potential to be beneficial in producing more energy, while also not taking up any valuable land, but more study is needed.