A Portable Thermoelectric Energy Harvesting Unit to Power Up Outdoor Sensors and Devices

摘要

This paper describes the analysis and design of a TEH prototype for powering up outdoor sensors and devices. The device employs the heat gradient developed between a metal plate that concentrates the solar radiation and a dissipative material. First, TEG modeling is presented to favor the estimation of the available power; next, a design of experiments is carried out to determine the maximum solar radiation during a day. Then, a performance analysis demonstrates conversion efficiencies higher that 20%, which surpasses the efficiency of any commercially available solar panel; while keeping the same superficial area of only 16cm². Thus, given such performance metric, a complete power unit is devised complementing the TEG operation with a 3.7V 550mAh Li-Po battery. The complete unit is able to provide enough energy to power up an Arduino-like based sensing unit and charge an on-board battery guaranteeing in that way a continuous operation. The total energy available from the prototype allows maintaining a battery discharge percentage of 50% when powering up a maximum load of 133.61mW during selected ranges.