Recharging a cellphone every few days is a manageable task - just find an outlet. Recharging the trillions of devices expected to be deployed on the Internet of Things over the next 20 years is not. Adding to the complexity: Humans increasingly are linking devices together into wireless sensor networks, sensing information from their environments and communicating that information back and forth. To harness the full power of wireless sensor networks for tasks such as monitoring patients' health remotely, saving lives during an emergency, or sensing environmental conditions, the wireless devices will have to be self-charging. This means that they must not only be capable of scavenging their energy from their surroundings but also be small and efficient enough that their energy requirements won't outstrip their meager supply. And given the number of devices required, they better be inexpensive. Over the last decade, a group of University of Virginia School of Engineering researchers has moved to the forefront of those systematically knocking down the barriers to creating self-sufficient sensors, also called nodes. One of these researchers is Assistant Professor Steven Bowers of UVA's Charles L. Brown Department of Electrical and Computer Engineering. This year, the National Science Foundation presented Bowers one of its prestigious CAREER Awards, enabling him to concentrate on maximizing the efficiency of the systems used to transmit and receive data from one node to another while moving communications from the crowded sub-5 GHz part of the communications spectrum to the 24 GHz range.