Detailed Axial Symmetrical Model of Large-Scale Underground Thermal Energy Storage

A. Dahash [1], M. B. Janetti [1], F. Ochs [1],
[1] Unit of Energy-Efficient Buildings, Institute of Structural Engineering and Material Science, University of Innsbruck, Innsbruck, Austria
Published in 2018

Seasonal thermal energy storage (STES) systems are key components for expanding the renewables share in the energy scheme as they offer the dispatchability and flexibility. Therefore, thermal behaviour of such systems is of interest. STES can influence the surroundings causing a violation to the hydro geological standards (e.g. groundwater’s temperature exceeding 20°C to 25°C). In this work, an underground tank and pit thermal energy storage (TES) are numerically modelled. The model considers the storage system and the surroundings around the TES. Then, the temperature distribution in the TES and the ground is investigated. In particular, thermal stratification in the TES is examined and, finally, interaction between TES and the surrounding ground is illustrated.