Installing floating solar photovoltaic panels on the more than 24,000 man-made reservoirs in the United States would generate about 10% of U.S. electricity production annually, according to the National Renewable Energy Laboratory (NREL). In an article in the journal “Environmental Science & Technology,” researchers of the organization revealed the energy potential for floating solar photovoltaics.
The first installation of floating solar panels was 10 years ago in Napa Valley, Calif., but the idea has yet to receive widespread acceptance in the United States. As of December 2017, the United States had seven installations of floating solar panels. Overseas, more than 100 sites have floating solar panel systems. Japan has 56 of the 70 largest floating solar panel systems.
“In the United States, it’s been a niche application; where in other places, it’s really been a necessity,” said Jordan Macknick, the lead energy-water-land analyst for NREL and principal investigator of the project that produced the paper published in the journal. “We’re expecting it to take off in the United States, especially in areas that are land-constrained and where there’s a major conflict between solar encroaching on farmland.”
About 2.1 million hectares of land could be saved if solar panels were installed on reservoirs instead of on the ground, according to NREL researchers. Some of the added benefits of installing the panels on lakes include reduced water evaporation and algae growth. Also, operating the solar panel systems near existing hydroelectric plants is expected lead to increased energy output and cost savings because of existing transmission infrastructure.
“Floating solar is a new industry enabled by the rapid drop in the price of solar (photovoltaic) modules,” said Adam Warren, co-author of the published paper and director of NREL’s Integrated Applications Center. “The cost of acquiring and developing land is becoming a larger part of the cost of a solar project. In some places, like islands, the price of land is quite high, and we are seeing a rapid adoption of floating solar.”