Energy-Harvesting Device Turns Wi-Fi Signals into Usable Power

Any device that sends out a Wi-Fi signal also emits terahertz waves — electromagnetic waves with a frequency somewhere between microwaves and infrared light. These high-frequency radiation waves, known as T-rays, are also produced by almost anything that registers a temperature including human bodies and inanimate objects. If harnessed, the concentrated power of terahertz waves could potentially serve as an alternate energy source; however, to date, terahertz waves are wasted energy, as there has been no practical way to capture and convert them into any usable form.