Recolector de micro energía Recolector de micro energía térmica térmica de baja temperatura

Abstract

The implementation of a micro energy harvester capable of powering commercial ultra low power electronics devices from small temperature gradients is described in this work.Commercial thermoelectric generators are suitable for high temperatures and gradients, therefore they are not adequate for extracting power from low temperature gradients sources like solar radiation or the human body heat. Exists wide interest on generating power from these sources, but the low generated power levels make difficult to couple them to commercial standard devices. In this work, Peltier effect modules are proposed as thermoelectric generators, coupled to a commercial low power conditioning circuit in order to extract as much energy as possible and couple its output to the operating voltage of commercial devices.Three Peltier modules were characterized, obtaining their internal resistance, generated power and Seebeck coefficient values, related to the power generation from temperature gradients. These values were used as guidelines for selecting the most appropriate module; also components for the power conditioning circuit were chosen by simulation and experimentally for interfacing the output of the module for boosting the low voltage generated in modules to standard regulated voltages, achieving conversion efficiencies of 18 to 30% with delivered power from 5 to 8 mW with gradients of 10 to 25 °C, generating 6 to 9 times more power than the required for a wireless network node.