A new study has revealed that government-managed reservoirs have the potential to generate enough solar energy to power about 100 million homes in the US annually.
For the first time, a survey done by the US Department of Energy National Renewable Energy Laboratory (NREL), has applied more precise factors, such as water depth and temperature, to estimate better the number of floating solar panels US reservoirs could support.
Officials at NREL claim that reservoirs have the potential to support enough floating solar panels to generate up to 1,476 terawatt hours, enough to power around 100 million homes annually. The figure represents the maximum energy output possible if each reservoir utilized its full capacity for floating solar panel installations.
According to the report, even under conservative projections, these reservoirs present significant potential for development, with the capacity to host projects totaling up to 77,000 megawatts.
“Accuracy could help developers more easily plan projects on U.S. reservoirs and help researchers better assess how these technologies fit into the country’s broader energy goals,” said NREL in a statement.
Floating solar potential
The global floating photovoltaics (FPV) industry is growing rapidly, with installations increasing by an average of 142 percent annually from 2014 to 2022.
FPV offers benefits over traditional ground-mounted solar, like better efficiency from cooling effects, co-benefits when paired with hydropower, and reduced water evaporation. “But we haven’t seen any large-scale installations, like at a large reservoir. In the United States, we don’t have a single project over 10 megawatts,” said Aaron Levine, a senior legal and regulatory analyst at NREL, in a statement.
Some countries, like South Korea, consider FPV vital for meeting solar energy goals. However, understanding FPV’s role in future energy systems is still in the early stages.
The technology faces challenges like water currents and ice. Researchers have started estimating FPV’s “technical potential,” or how much can realistically be developed. While some studies focused on specific reservoirs, few have used detailed, location-based methods to assess FPV potential.
The study aims to develop a more precise method for estimating FPV’s potential in US reservoirs, focusing only on technical limitations without considering other factors like regulations or environmental impacts. The effort specifically looks at federally managed US reservoirs.
Assessing solar viability
NREL states that while previous studies have concentrated on estimating the energy generation potential of floating solar panels, this study is the first to assess which water sources are suitable for such systems.
Some reservoirs have circumstances like frigid temperatures, shallow depths, or steep bottoms that make it difficult to secure solar panels, or shipping traffic that causes wakes that could harm the floating infrastructure.