Garden soil‐based microbial fuel cell equipped with an amplification system coupled with a secondary PV ‐assisted module: Utilization as eco‐sustainable electrical power supply for carbon monoxide gas sensor

Abstract Autonomous environmental telemetry requires continuous, maintenance‐free power sources capable of driving commercial sensing electronics. This study reports the development of a self‐powered bio‐electrochemical sensing platform utilizing a garden soil‐based microbial fuel cell (s‐MFC) coupled with a hybrid power management system (PMS) to drive a commercial off‐the‐shelf (COTS) carbon monoxide (CO) gas sensor. Operating under a sub‐volt thermodynamic limit, the raw s‐MFC generated a steady‐state open‐circuit voltage of 0.5 V, governed by the extracellular electron transfer of indigenous electroactive bacteria. To overcome this voltage bottleneck and satisfy the 3.0 V nominal operating threshold of the commercial sensor, an ultra‐low‐power DC/DC boost converter was engineered. The PMS incorporates a high‐efficiency switching network driven by an operational amplifier and an NE555 timer configured in an astable multivibrator topology, synergistically integrated with a miniature photovoltaic (PV) solar module to sustain the active control loop and mitigate internal power overhead. Continuous 15‐day galvanostatic testing demonstrated that the hybrid PMS successfully achieved a 6‐fold voltage amplification, delivering a regulated 3.0 V rail to the gas‐diffusion sensor while yielding a 70% increase in overall energy harvesting efficiency. These findings validate the scalability of soil bio‐electrochemical systems combined with hybrid solid‐state power conditioning to achieve long‐term energetic autonomy for terrestrial micro‐telemetry networks.