Researchers at the Energy Department's National Renewable Energy Laboratory (NREL) said that installing floating solar photovoltaics on the more than 24,000 man-made U.S. reservoirs could generate about 10% of the nation’s annual electricity production.

Their findings were published in the article "Floating PV: Assessing the Technical Potential of Photovoltaic Systems on Man-Made Water Bodies in the Continental U.S.” in the journal Environmental Science & Technology.

NREL said that the US was the first to demonstrate floating PV panels around 10 years ago using pontoons on an irrigation pond in California. However, the idea has not received widespread national acceptance, and only seven floating PV sites were installed as of December 2017. Floating PV sites are being deployed overseas, however, with more than 100 sites, including Japan, which hosts 56 of the 70 largest floating PV installations.

(Read "Snapshot of the state of floating solar energy systems.")

The NREL researchers said that about 2.1 million hectares of land could be saved if solar panels were installed on bodies of water instead of on the ground. Floating PV may come with additional benefits, including reduced water evaporation and algae growth on bodies of water.

Floating solar may emerge as a new industry enabled by the drop in the price of solar PV modules, the NREL research team said. In particular, the cost of acquiring and developing land is becoming a larger part of the cost of a solar project.

Funding for the analysis came from NREL’s Laboratory Directed Research and Development program, an internal source of research money.