Harvesting thermoelectric energy to power CO2 sensor includingcharging smaller devices

Sammanfattning

This Bachelor thesis investigates the feasibility of developing a self-sustainingsafety system by harvesting electrical energy from waste heat in wood-burningstoves. Harnessing the Seebeck effect, the thermal gradient between the stove’s hot surface and the surrounding air is converted to electricity via thermoelectric generators (TEGs). The project addresses the need for reliable air quality monitoring in crisis situations, such as blackouts, where the power grid is unavailable and conventional batteries have limited lifespans. The core solution is a printed circuit board (PCB) integrating an energy efficient ESP32-S3 microcontroller. To manage the unstable voltage from the TEGs, Maximum Power Point Control (MPPC) is employed for dynamic impedance matching to ensure maximum power extraction.The system includes a linear charge management controller for a battery buffer to ensure operation when the stove is not in use. A major emphasis has been placedon making the energy harvesting analogue, enabling cold starts if the integrated battery bank is empty. Experimental results from testing on a Contura 510 stove demonstrate that the system can generate a stable 5V output, meeting the requirements for charging mobile phones with USB-C and powering integrated sensors. The thesis emphasises the importance of thermal management. By simulating airflow with passive cooling, a sufficient temperature gradient was maintained for continuous harvesting. This work proves that thermoelectric harvesting is a viable method for creating autonomous safety systems in domestic environments.