Numerical investigation of energy piles for thermal energy storage applications

In the context of increasing energy demand for heating, cooling, and domestic hot water production, Thermal Energy Storage (TES) is crucial for optimizing resource utilization, reducing grid dependency, and facilitating the transition towards sustainable energy systems. Energy geostructures (EGs), particularly energy piles (EPs), present a promising opportunity not only for conventional building heating and cooling but also for long-term thermal energy storage, effectively transforming the subsurface into a “thermal battery”[1]. This study utilizes numerical modelling to investigate the potential use of an energy pile group for seasonal thermal energy storage (STES) sourced from solar thermal collectors. Different configurations were analyzed by varying pile spacing, pipe circuit type, and charge/discharge temperatures. Preliminary results indicate the system's feasibility from the perspective of thermal performance, highlighting the potential need for initial ground preheating.