You might have not notice that your surrounding is full with large amount of electromagnetic energy transmitted from various electronics sources including mobile phones networks, radio broadcast, wireless broadband, television transmitters, and even satellite communications systems.
A team of researchers at Georgia Tech School of Electrical and Computer Engineering has made experiments using inkjet printing technology to put together sensors, antennas and energy scavenging capabilities on a thin piece of paper using flexible polymers.
And according Manos Tentzeris, a professor in the Georgia Tech School of Electrical and Computer Engineering, currently, the scavenging technology can take advantage of frequencies from FM radio to radar, offering a range of 100 Mhz to 15 GHz or higher. The sensors on the thin paper will capture the frequencies and convert it from AC to DC current and then store it in capacitors and batteries.
The team at Georgia Tech School of Electrical and Computer Engineering has able to generate hundreds of milliwatts by harvesting the energy from TV bands alone, while it is expected that by perfecting the technology into multi-band harvester, by exploiting a range of electromagnetic bands to generate even more electricity to self powered small electronic devices, including a variety of sensors and microprocessors.
The team is also looking at combining the energy scavenging technology with supercapacitors and cycled operation so that the energy builds up in a battery-like superconductor and is utilized once the required level is reached. The team expects this approach would be able to power devices requiring over 50 milliwatts.
The researchers have already successfully operated a temperature sensor using electromagnetic energy captured from a television station that was half a kilometer away. They are now preparing another demonstration in which a microprocessor-based microcontroller would be activated simply by holding it in the air.
Furthermore, the team also clarify that the scavenged energy could also help a solar element to charge a battery during the day time, while at night, the scavenged energy would continue to harvest available electromagnetic energy for charging the battery, in this way, it will prevent any small mobile devices from discharging.
Alternatively, the scavenged energy could also be utilized as another system backup, whenever a battery failed to perform its duties due to unexpected technical errors, and thus allowing the system to transmit a wireless signal and keep maintaining critical functions.
The scavenged energy system should be one of the technology that could help to generate more alternative energy from untapped electromagnetical signal from our daily gadgets.
[ Source: Gizmag ]