In a 2017 study published in the journal Nature Communications, Columbia University biophysicist Dr. Ozgur Sahin and colleagues assert that evaporation from reservoirs and lakes in the U.S. could produce 325 gigawatts of energy. That’s almost 70 percent of the average annual amount of energy the U.S. produces now.
This research marks the first time evaporation’s capacity as a renewable energy source has been studied. Although the new findings come from experiments conducted in a lab, researchers said they were excited about the real-world possibilities.
How Evaporation Creates Power
Evaporation can create usable power with the help of some microscopic friends. Sahin and his colleagues have developed a machine that uses a shutter to control humidity. The fluctuations in humidity encourage bacterial spores to contract and swell.
The energy from the movement of the spores is then transferred to a generator, where it is converted into electricity. Sahin and team call the machine they’ve invented the Evaporation Engine. Their new study was meant to examine how much energy the machine could produce in the U.S.
Solving Renewable Energy Problems
As the U.S. and the world try to offset the climate changing effects of burning fossil fuels, solar and wind energy have become key players in the energy industry. However, opponents of these renewable energy sources often point out that these methods cannot generate sufficient electricity when the sun isn’t shining or the wind isn’t blowing.
And while the go-to solution has been large batteries that can store solar and wind power, these batteries must be manufactured using dangerous chemicals. They also create an additional financial hurdle for those who want to generate solar and wind power.
Evaporation, however, wouldn’t require a battery, Sahin and colleagues pointed out. And evaporation tech would be able to generate electricity on demand.
As drought concerns grow in the Western U.S. and other regions, saving water has become a priority for state governments. Those same state governments might be eager to get their hands on evaporation technology if Sahin’s findings ring true.
Roughly half of the water that evaporates could be saved during the process of harvesting energy, according to this study. In the scenario Sahin and his research team modeled, that could come to an estimated 25 trillions gallons of water each year. That’s around 20 percent of the water used in the U.S. annually.
Where It Could Work Best
Although Sahin and team said evaporation could be useful anywhere, they noted that places with hotter weather would likely see the most benefit from evaporation tech. They specifically mentioned California, Nevada, and Arizona.
These states also happen to struggle with water loss and drought. That means they could also benefit from the water-saving potential of evaporation technology.
The Future of Evaporation
Sahin said in a press release that evaporation tech could be used as a primary power source in the U.S. And when the conditions are right, solar and wind energy could supplement it.
This technology is still in its infancy, but Sahin and colleagues are refining the process to improve its efficiency. They said they hope to test evaporation tech in a greenhouse or on a lake or reservoir in the near future.
If you’re looking to reduce your energy footprint, one thing you can do is use ENERGY STAR rated appliances that do a better job of using energy. For small air conditioners, this could mean using a double hose model that funnels warm air outside of the home in order to better cool the air inside.