In a transient state of heat transmission, the spatio-temporal variability of thermal properties needs to be addressed. To this end, the present study introduces a new experimental approach.

Responding to the modernization society, an alternative energy resource is required. Particularly, the geothermal system, which can provide an efficient cooling/heating to the building, is one of the most desirable technologies as an eco-friendly renewable energy. This study contributes to the accomplishment of a development on numerical modeling which contained the same condition as the field investigation, that was implemented in COMSOL Multiphysics of the Finite Element Method (FEM) based. Consequently, the effect of the long-term performance of the geothermal system and thermal recovery in the ground and the ground temperature through the residual thermal energy were estimated.

• An experimental platform made up of 4 BHEs is used to monitor the long term evolution of the ground temperature field around a thermally activated BHE and highlights the impact of groundwater flows • A methodology to characterize the main hydro-geothermal parameters of the ground is developed, based on an finite line source model-based analytical solution and that considers conductive, advective and dispersive heat transfers • A good agreement is observed between predicted and measured ground temperature evolutions.

Based on in-situ temperature measurements and computational simulations, the present study estimates the geothermal gradients and recoverable energy potential available in a high-organic content landfill cell after 11 years of closure. A total of 190 in-situ subsurface landfill temperature measurements were available with temperatures of up to 52.9°C. A two-dimensional heat transfer in porous media finite-element model was constructed to simulate a representative cross section of the landfill, assuming no unsaturated flow during up to 100 years of heat production.

TRT is the international standard method to characterize thermal properties required for energy geo structures design. Routine TRTs are performed in small diameter boreholes. However, their application in large diameter energy piles is continuously increasing. The implementation of these tests faces many logistic challenges, which affect the accuracy of results. This paper applies a stochastic method based on Bayes’ Theorem to determine thermal properties from a TRT executed on a large diameter energy pile in Mexico. The results highlight the potential of the Bayesian Framework to provide reliable estimations and quantify uncertainties coherently. This approach allows obtaining more realistic results.