The use of Microbial Fuel Cells as power sources in rural or remote locations can solve issues related with power
availability and wastewater cleaning. Furthermore, the application of such technology in wireless smart sensors
applied to wastewater treatment plants can also help in water quality monitoring, increasing the process autonomy and reliability. A trustworthy power source needs to have a predictable and repeatable behavior, which
cannot be achieved without adequate models and supporting hardware for energy regulation and storage. The
work herein described proposes a steady-state model, represented by an electric circuit made of passive components. This model was first applied to a specific 28 mL air-cathode Microbial Fuel Cells working with artificial
wastewater and using graphite brush anodes. Afterwards, the model was further validated by applying it to a
larger reactor and to other bibliographic records. The goal of the study is to propose a method for finding a
Microbial Fuel Cell model to be used with maximum power point tracking research, guaranteeing the best-case
scenario for Microbial Fuel Cell operation as a power source. The reactors used in this study were analyzed by
relating time and voltage development, both in colonization and in polarization studies. A mathematical relationship model was developed and proposed allowing to separate MFC’s behavior, concerning energy production, in to meaningful components. From the experimental data the method was used to obtain a two-component
circuit model that describes the power behavior of this specific Microbial Fuel Cell topology. The same method
can be used to described other MFC.