Supercapacitors accumulating energy harvesting from stacked sediment microbial fuel cells and boosting input power for power management systems

Supercapacitors, are commonly connected to the sediment microbial fuel cell (SMFC) and then serves as the input source for the power management system (PMS). To compare and analyze functions of supercapacitors in SMFC energy harvesting, PMSs (PMS I and PMS II) are powered by SMFC stack or charged supercapacitors as the input source. Tests indicate that the charged supercapacitor results in a higher input power and a larger output power. In addition, the overall efficiency of PMSs is rarely affected by the capacitance, but the initial voltage of the supercapacitor. By charging supercapacitors connected in parallel and then discharging them in series, the overall power efficiency of PMS II is increased from 44.33% to 69.52%. In conclusion, supercapacitors firstly storing SMFC energy is beneficial to provide sufficient energy, resulting in an improved PMS performance. Further, these results can be useful and informative to PMS design for efficiently harvesting and utilize MFC energy.