Bioengineers, through the exceptional utilization of engineered artificial muscles, have invented the world’s very first engine that runs on one of the most common processes we witness in our everyday lives: evaporation.
The small device made by researchers at the Columbia University, is a completely functional engine that can make 1.8 microwatts of energy, which is the ample amount of energy for powering LED lights or even a tiny car- at the cost of 5 dollars. It works by drawing power from a source which was never even considered as a proper power source capable of being harnessed.
“Engineered systems rarely, if ever, use evaporation as sources of energy, despite myriad examples of such adaptations in the biological world,” a paper published in Nature by a team of authors, including researchers Xi Chen, Ozgur Sahin and others, claimed.
While seeming to violate the laws of physics by creating energy from nothing, the engine, which measures less than four inches on each side, is able to generate energy from extremely small temperature differences in ambient evaporation.
Thanks to HYDRAs or Hygroscopy-driven artificial muscles, which are termed by the researchers as the engines ‘living parts’, which expand and contract with infinitesimal alterations in moisture content. The breakthrough came when Columbia researchers discovered that some bacterial spores increase in size when they absorb moist air and shrink when they are dry.
“And HYDRAs change shape in really quite a dramatic way: they can almost quadruple in length,” Ozgur Sahin, leader of the Columbia University team, told Popular Mechanics.
Making use of this process, the team created ‘evaporation engines’ to put the force to work. A set of shutters were put into place so as to lift when the artificial muscles extend, expel air and return to their starting position. This principle was applied to a rotary engine which spins when only one side is shown to the moist air and the other side expels it.
“This is a very, very impressive breakthrough,” Peter Fratzl, a biomaterial researcher at the Max Planck Institute of Colloids and Interfaces in Potsdam, Germany said. “The engine is essentially harvesting useful amounts of energy from the infinitely small and naturally occurring gradients near the surface of water. These tiny temperature gradients exist everywhere, even in some of the most remote places on Earth.”