Low-Level Kinetic-Energy-Powered Temperature Sensing System

Powering modern nanowatt sensors from omnipresent low-level kinetic energy: This study investigates the power levels produced by a varying-capacitance kinetic energy harvesting system. A model system consisting of a uniformly driven rotating capacitor was built to develop an accurate output power performance model. We found a quantitative linear relationship between the rectified output current and the input applied bias voltage, driving frequency, and capacitance variation. We also demonstrate that our variable capacitor system is equivalent to a fixed capacitor driven with an alternating current power source. Both the fixed-capacitance and varying-capacitance energy harvesting systems recharge a three-volt battery, which in turn powers a custom ultralow-power-consuming temperature sensor system.