Energy-Harvesting Power Supply

The design team was charged with finding an overlooked energy source and harvesting it to extract usable electric power. The team chose the magnetic field created by overhead power distribution lines, which yielded enough energy to power small electronics such as a Wi-Fi hotspot, a communications repeater, a phone, or a light that could be easily deployed in rural areas. The team built a device that clamps onto a 14kV power line. Using a current transformer, the device is able to induce usable alternating current in a circuit that is then rectified, smoothed, and regulated out to direct current via a secondary circuit. It is then able to provide 12 watts of power for the user’s consumption. The device is equipped with a metering chip and a radio frequency communications module managed by a microcontroller. This circuitry relays the appropriate metrics to the user. The device information is transmitted to a computer equipped with a communications receiver module and displayed on a custom graphical user interface. Data made available to the user reflects voltage, current, and power levels being consumed. The harvested power is available to the user through multiple outlets, including a USB plug and general two-prong/barrel DC connectors.