Impact of permeability heterogeneity on geothermal battery energy storage

Abstract

In the emergence of new technologies to harness renewable energy, industrial-scale storage of heated water in a geothermal system is a promising technique. A porous, permeable medium, bounded by a poorly thermally conductive/convective overburden and underburden, can be used for transient subsurface thermal storage. The reservoir in this concept forms a geothermal battery. As a very simplified scenario, consider a single well injecting and producing hot water diurnally or seasonally. The source of the hot water could be solar-heated water, for example, or possibly even water heated from the excess regional electricity supply. For that situation, this study investigates the influence of spatial permeability heterogeneity on heat recovery, and the distributions of temperature and pressure inside the reservoir. Four heterogeneous models are created from lognormal distributions of permeability by varying the standard deviations while keeping the mean absolute permeability at 100 mD. The injection pressure experienced while pumping into a candidate formation is affected by heterogeneity; higher bottom hole pressure is required to inject water into a more heterogeneous reservoir. The spatial distribution of temperature is less affected by permeability heterogeneity. In the simulations carried out, 91% of the heat is recovered after the 30 th cycle of injection/production operation in all cases proving less impact of heterogeneity on heat recovery for fixed injection and production rates.

A Full-Scale Experimental Investigation of an Advanced Geothermal Energy Storage System

“…The thickness of the reservoir affects the thermal front evolution, where the temperature will advance farther for a thinner formation. Regarding the flow rate, the thermal front will move farther for a high injection flow rate [1,2,3]. Similar studies are also performed, and the results are consistent with these findings [4,5].…”

Effect of Pore-Throat Heterogeneity on Gas–Water Flow in Tight Gas Reservoirs: From Micro- to Centimeter Scale

“…Figure shows the geometry and meshing results of the homogeneous, weakly heterogeneous, and complex strongly heterogeneous microfluidic models. The homogeneous model was filled with a single spherical skeleton particle (1.8 μm), and the heterogeneous model was filled with spherical particles with sizes of 0.7 and 1.8 μm, , respectively. Figure gives the results of gas–water saturation distribution and interface area visualization in the homogeneous, weakly heterogeneous, and complex strongly heterogeneous models during the gas flooding process.…”

Feasibility analysis of storing solar energy in heterogeneous deep aquifer by hot water circulation: Insights from coupled hydro-thermo modeling

“…However, horizontal and vertical permeability anisotropies in layered sedimentary rocks may lead to asymmetric temperature and pressure profiles away from a production/injection well, which needs to be considered when planning the optimal spacing between production and injection wells (Panja et al, 2021a). Numerical simulations indicate formation heterogeneity has insignificant impact on huff-puff type thermal storage system (Panja et al, 2021b). Winterleitner et al (2018) found that meter-scale heterogeneities and density-driven flow significantly influence the performance of high temperature aquifer thermal energy storage.…”