If a storm rolls in while you’re at work, and you’re wondering if you left your bedroom window open, you can tell via an internet connection – ifthat window is equipped with a contact sensor. Ordinarily, such sensors require electrical wiring, and a battery or mains power. A new window system developed by Germany’s Fraunhofer Institute for Integrated Circuits, however, works without wires, and draws its power from the environment around it. .. Continue Reading Wireless, battery-less system designed to alert users to windows left open