In what is believed to be the first analysis of evaporation as a renewable energy source, researchers from Columbia University have determined that US lakes and reservoirs could generate a whopping 325 gigawatts worth of clean energy, which would account for approximately 70% of current US electricity production.
Researchers from Columbia University have this week published their findings evaluating the potential of evaporation as a renewable energy source in the September 26 issue of the journal Nature Communications. The study, Potential for natural evaporation as a reliable renewable energy resource, was designed to test how much power can be generated by using what the researchers call the Evaporation Engine, a machine developed by Columbia University biophysicist Ozgur Sahin which controls humidity with a shutter that opens and closes, prompting bacterial spores to expand and contract.
“We have the technology to harness energy from wind, water and the sun, but evaporation is just as powerful,” Ozgur Sahin, the study’s senior author. “We can now put a number on its potential.”
The researchers further conclude that evaporation can be generated only when necessary, compared to traditional renewable energy sources which are variable and reliant upon outside sources such as wind and sunshine. The normal solution to variable energy generation is to combine it with battery storage, which while efficient, nevertheless requires the use of expensive and sometimes toxic materials in manufacturing.
“Evaporation comes with a natural battery,” said study lead author, Ahmet-Hamdi Cavusoglu, a graduate student at Columbia. “You can make it your main source of power and draw on solar and wind when they’re available.”
The study also found that evaporation technology can also save water, with the researchers estimating that half of the water naturally lost from lakes and reservoirs through evaporation could be saved during the process of harvesting evaporation for energy — which came to around 25 trillion gallons of water a year, or about a fifth of the water Americans consume in a year.