EnergyHarvester
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MIT researchers develop chip that can harvest energy from multiple sources
We've seen a number of different devices that can harvest energy from various sources, but none quite like this new chip developed by a team of MIT researchers. It's able to harvest energy from three different sources simultaneously: light, heat and vibrations. The key to that is a sophisticated control system that's able to rapidly switch between the three sources at all times to prevent any of that energy from going to waste (and not draw too much power itself), with energy from the secondary sources stored in capacitors to be picked up later -- as opposed to existing systems that simply switch between sources based on what's most plentiful. As doctoral student Saurav Bandyopadhyay explains, efficiently managing those disparate sources could be a "big advantage since many of these sources are intermittent and unpredictable," and it could in turn lead to the chip being used in a range of different applications where batteries or existing energy harvesting methods just aren't enough: everything from environmental sensors in remote locations to biomedical devices.
Georgia Tech engineers pull energy out of atmospheric hat, go on electromagnetic scavenger hunt
Mankind's about to plunge into the depths of a wireless sensor-powering ether binge -- braincell annihilating vapors not included. Spearheaded by Georgia Institute of Technology's professor Manos Tentzeris and his engineering team, this ambient energy scavenging tech harnesses electromagnetic frequencies in the 100MHz - 15GHz range -- anything from your FM car radio to radar -- and converts it into a useable DC power source. So, it's free energy -- kind of. The cheap, self-powering paper or flexible polymer-based sensors are created using standard inkjet printers and Tentzeris' "unique in-house recipe" of circuit-building silver nanoparticles. Current testing hasn't yet yielded significant enough wattage to power your PS3 Slim, but it could soon via the help of supercapacitors and future solar cell integration. Imagine clothing embedded with health-monitoring biometric sensors, airport security run by something other than aloof TSA agents, or even spoilage-aware drink cartons -- milk that tells you when it's gone sour. The invisible radio band-charged possibilities are endless, but with storage still in the microwatt to one milliwatt range, it's more concept than solid vaporware reality.
Tiny, energy-scavenging generators could have big impact
They're far from the only ones working on tiny, energy-harvesting generators, but a group of researchers from the University of Michigan may well be farther along than most. Unlike some similar devices, their generator is able to scavenge even the slightest bits of energy from arbitrary, non-periodic vibrations in everything from bridges to the human body. That may not add up to a huge amount of energy, but the researchers say the generators are able to scrape together enough to keep a wrist watch or a wireless sensor running, or potentially power even a pacemaker by the person's own body movements. Of course, the device likely won't be powering anything beyond the lab anytime soon -- the researchers are still going through various prototypes using different types of energy conversion, and are naturally working to patent it as well.
Researchers develop tiny, autonomous piezoelectric energy harvester
Folks have long been using piezoelectric devices to harvest energy in everything from dance floors to parking lots, but a group of European researchers have now shown off some novel uses for the technology at the recent International Electron Devices Meeting that could see even more of the self-sufficient devices put to use. Their big breakthrough is that they've managed to shrink a piezoelectric device down to "micromachine" size, which was apparently possible in part as a result of using aluminum nitride instead of lead zirconate titanate as the piezoelectric material, thereby making the devices easier to manufacture. Their first such device is a wireless temperature sensor, which is not only extremely tiny, but is able to function autonomously by harvesting energy from vibrations and transmit temperature information to a base station at 15 second intervals. Of course, the researchers say that is just the beginning, and they see similar devices eventually being used in everything from tire-pressure monitoring systems to predictive maintenance of any moving or rotating machine parts.
EnOcean harvesting power from the environment, not batteries
Remember EnOcean's batteryless / wireless light switches on display last year? Don't sweat it, neither did we. Still, that hasn't stopped EnOcean from experimenting with battery-less sensors which harvest electricity from vibrations (pictured) and temperature differentials. According to EnOcean, their prototype thermal-differential sensor attached to say, a water pipe, can harvest up to 50-milliwatts as long as one surface is 3-degrees Celsius higher or lower than the immediate environment. While that pales in compaison to batteries, it's still enough power to transmit a tweaked RF signal as far as 300-meters in an open warehouse or 30-meters through walls. Nearby sensors can also act as relays to extend signal transmission. Link the sensors with a thermostat and you can create micro-climates around the home; link 'em to a home automation system and control your house without the need to run power and Cat 5 / WiFi everywhere. Now someone get those X10 spammers home automators on the horn, we smell a business op.
