Evaporation. It seems insignificant to our senses, but it is a force more powerful than wind and waves. It resists gravity and deposits snow on Mt. Everest.
Now we are able to harness this incredible force, adding it to the list of clean, renewable energy sources than can replace fossil fuels. It will allow self-sustaining power in places devoid of sunlight, such as the ocean floor. Sensors can be powered by an evaporation unit, giving us real-time monitoring of natural resources.
Researchers at Columbia University say the energy could one day be made strong enough to power full-sized vehicles and create giant floating power stations.
Ozgur Sahin and his team created two devices that are powered by evaporation alone, as demonstrated in this mesmerizing video.
The first is an artificial muscle that continually opens and closes a set of shutters, making a self-sustaining cycle of motion. This evaporation-driven piston was coupled to a generator and caused a small light to flash.
The second device—the Moisture Mill—contains a plastic wheel that sits halfway in dry air and halfway in humidity. The evaporative force causes the wheel to rotate continuously and serve as a rotary engine. It produced enough power to move a small toy car.
The technology is beautiful in its simplicity. Bacterial spores shrink and swell with changing humidity. This miniscule phenomenon pushes and pulls other objects with a force greater than some current engineering materials. Concentrating this on “spore tape” in certain ways, while controlling their exposure to humidity, creates the self-sustaining motion which is turned to useful energy.
As Peter Tertzakian described in his book, “A Thousand Barrels A Second,” we are at the dawn of a new energy age. While fossil fuels contributed to some of our achievements in the Industrial Age, the costs to environmental health and human health are too great. Fossil fuels are also finite and localized, fueling conflict around the world.
Evaporative energy joins the host of rapidly advancing renewable technologies that will propel us into that cleaner, more peaceful era.