In a world where tireless efforts are being made to save on energy and also generate more, researchers have developed a device with a mechanism to capture and harness energy transmitted by sources such as radio and television transmitters, cell phone networks and satellite communications systems. This energy though has been with us, has never been well utilised or thought as a major source of energy until recently.
The device features a five cell meta-material array made up of five fiberglass and copper conductors on a circuit board which is responsible for the energy conversion process. The device is made using inkjet printers which combine sensors, antennas and energy-scavenging capabilities on paper or flexible polymers.
Communication devices transmit energy in many different frequency ranges. This energy is captured converting it from AC to DC and then stores it in capacitors and batteries.
The technology can utilise frequencies from FM radio to radar, a range spanning 100 megahertz to 15 gigahertz or higher.TV bands are also a good source of energy that can give energy amounting to hundreds of microwatts with multi-band systems expected to generate one millliwatt or more. This amount of power is enough to operate many small electronic devices.
Scavenged energy could assist a solar element to charge a battery during the day. At night, when solar cells don’t provide power, scavenged energy would continue to increase the battery charge or would prevent discharging.
Utilizing ambient electromagnetic energy could provide a form of system backup. If a battery or a solar-collector/battery package failed completely, the scavenged energy could allow the system to transmit a wireless distress signal while also potentially maintaining critical functionalities.
By scavenging this ambient energy from the air around us, the technique could provide a new way to power networks of wireless sensors, microprocessors and communications chips.