Harvesters gather energy from the ether, power lightweight systems

There’s no free lunch, right? Your mom and dad probably told you as much. So surely we can’t extract energy from thin air. Or can we? Actually, the human body, factory machines, radios of various types, and many other things emit energy in the form of heat, vibration, or RF waves. And it’s looking increasingly plausible that designers can devise systems that scavenge the stray energy and convert it for use in powering systems—albeit very low-power ones. You won’t soon see a mobile handset powered from the ether, but potential realistic applications include portable medical monitors and even home-automation devices.
Energy harvesting or scavenging is more about enabling compelling new applications than about saving money on power. Tech-industry visionaries have for some time been speaking of an era of ubiquitous processors embedded into the fabric of our lives. Borrowing a passage from our 50th anniversary issue, Texas Instruments Principal Fellow Gene Frantz said, “You can almost say that we are on the path to the vanishing product—where the product will be so small and insignificant in size, but so significant in capability, that we really don’t know where we have it; we just know we have it.” It’s easy to imagine many such microprocessor-based devices both on our persons and in places such as a smart light switch or thermostat.

EDN