In the first analysis of using evaporation as renewable energy, Columbia University scientists have found that evaporation-to-power devices on lakes and reservoirs could generate 325 gigawatts of electricity—about 70 percent of current U.S. production.”The method also could save large amounts of water in drought-prone regions and be available around the clock, getting around the cyclical challenges of solar and wind, they said.

“We have the technology to harness energy from wind, water and the sun, but evaporation is just as powerful,” said biophysicist Ozgur Sahin, a co-author of the study published today in Nature Communications. “We can now put a number on its potential.” Because evaporation occurs continuously from water sources—even at night—the technology, in theory, could provide a constant source of power. Manipulating shutters on the system would allow it to be turned on and off. “Evaporation comes with a natural battery,” said lead author Ahmet-Hamdi Cavusoglu.

Jordan Macknick, an environmental analyst at the National Renewable Energy Laboratory who did not participate in the research, noted that the study did not address the potential environmental and health impacts of such technologies placed at reservoirs. “There are many complicating factors,” he said.”