Nearly everywhere you go little Wi-Fi signals are bouncing off you. Just checking what Wi-Fi is available around your house or in your building likely reveals multiple networks quietly blasting away. More and more public places have Wi-Fi available, to the point I wasn’t really surprised when my mechanic offered Wi-Fi for waiting customers.
Relax! This article isn’t about the possible negative side effects of Wi-Fi on your health or your brain. It’s about the potential energy to be found in all those Wi-Fi signals, cell phone calls and even thunderstorms. All of those things create electromagnetic fields, and Dennis Siegel, a digital media student at the University of the Arts in Bremen, Germany, figured there should be some way to harness all those fields to produce something useful.
With that theory in mind, Siegel designed and built a device that taps into electromagnetic fields and harvests the potential energy. In fact, he built two. One device feeds on frequencies below 100Hz, produced by main electric lines, and the other siphons energy from higher frequencies, such as radio frequencies and Wi-Fi. The end result can recharge an AA battery in about a day.
As might be expected, the design behind the gadgets was “really time-consuming and expensive” for someone without an engineering background. “It was quite hard to find out the correct lengths and coil windings, especially to make the whole system suitable for a larger field of frequencies,” Siegel told Fast Company.
While a day to recharge a single AA battery doesn’t seem very impressive right now, the design might be improved if a trained engineer got his hands on it, particularly if the device turns out to have commercial applications. Consider how amazing it would be if the harvester could be miniaturized so that by using your cell phone, or even carrying it about, it continually recharges.
Below you’ll find a short video about the harvester.