Near-Surface Geothermal Energy Harvesting: A Study on Available Energy Budgets and Temperature Gradients

This study reports on the design of a precision temperature soil probe and on its first application to assess the thermal profile of shallow subsurface environments, in order to evaluate the potential of near-surface geothermal-thermoelectric systems. The aim is to accurately monitor temperature gradients and temperature trends in the soil vs. the ambient over extended periods of time and under harsh environmental conditions. This knowledge is essential for reducing complexity in geothermal soil probe design and for optimizing the thermal coupling of soil and ambient to a thermoelectric generator (TEG), thereby improving system efficiency in real-world deployment.