Electrical Energy Harvesting from Pot Plants

In recent years, energy harvesting studies have grown significantly. Energy recovery for low power applications is assuming considerable importance for powering non-essential auxiliary circuits. Among the various sources of energy that can be found in nature, in this paper we consider the Plant-Microbial Fuel Cell (P-MFC), fed by bacteria present in the roots of plants. We show a preliminary study for the optimization of P-MFC energy harvesting. The system considered is a collection of series and parallel connected pot plants. The main principle of operation is the one of a microbial cell. Plants through photosynthesis produce sugars that are subsequently released into the soil through the roots. Bacteria present near the roots consume these sugars and produce ions. Therefore, thanks to an redox process, by introducing two electrodes into the ground (anode and cathode) it is possible to obtain a potential difference that can be exploited as an energy source for indefinitely feeding electronic devices, even where it is not possible to have a direct connection to an outlet.