National Renewable Energy Laboratory (NREL) researchers estimate that installing floating solar photovoltaics on the more than 24,000 man-made U.S. reservoirs could generate about 10 percent of the nation’s annual electricity production. Their findings, published in the journal Environmental Science & Technology, reveal for the first time the potential for floating PV to produce electricity in the United States.

While the United States was the first to demonstrate floating PV panels—with the first installation occurring 10 years ago on pontoons on an irrigation pond in Napa Valley, California—the idea has not received widespread national acceptance. The U.S. focus has primarily been on installing large-scale, ground-mounted solar panels, and only had seven floating PV sites as of December 2017. Floating PV sites are being deployed more overseas, however, with more than 100 sites as of the end of last year. Japan, for example, is home to 56 of the 70 largest floating PV installations.

 Floating PV being installed in Walden, Colorado. (Photo by Dennnis Schroeder/NREL)