Publications related to Enhanced geothermal system

Solar-assisted clean steam generator, a cleaner production approach for sustainable healthcare facilities

Fernando Porté Agel, Mohammad Jamshidmofid, Ahmad Arabkoohsar

Healthcare sector buildings, particularly hospitals, significantly contribute to global energy consumption and greenhouse gas emissions. Hospitals require a substantial amount of steam, including the essential hygienic or " clean steam, " that is currently ...

Elsevier Sci Ltd2024

Reactivation of variably sealed joints and permeability enhancement in geothermal reservoir rocks

Alexandra Roma Larisa Kushnir, Michael Heap

Hydraulic stimulation of enhanced deep geothermal reservoirs commonly targets pre-existing joint networks with the goal of increasing reservoir permeability. Here, we study the permeability and strength of joint-free and jointed Buntsandstein sandstones fr ...

2023

A fully-coupled highly-parallelized geomechanical simulator for assessing induced seismicity

Jean-François Molinari, Brice Tanguy Alphonse Lecampion, Guillaume Anciaux, Nicolas Richart, Emil Gallyamov

Induced seismicity caused by anthropogenic modification of the subsurface effective stress state has been observed in a number of industrial applications -- from hydrocarbon extraction (e.g., Groningen [1]), drilling waste-water disposal (e.g., [2]) to the ...

2023

Single-Well Pore Pressure Preconditioning for Enhanced Geothermal System Stimulation

Marie Estelle Solange Violay, Mathias Alexandre David Lebihain, Barnaby Padraig Fryer

The stress state is an important parameter in terms of both earthquake nucleation and rupture. Here, a new stimulation technique is proposed for Enhanced Geothermal Systems (EGSs), which have previously been burdened with a number of high-profile incidence ...

2023

Fluid flow through microcracked and fractured granitic reservoirs

Marie Estelle Solange Violay, Lucille Jocelyne Nadine Carbillet, Michael Heap

The permeability of crustal rocks and rock-masses dictates the efficiency of hydrothermal circulation and therefore the productivity of geothermal resources. In this study, we find by monitoring P-wave velocity that thermal microcracking in Lanhélin granit ...

2023

Three-dimensional fluid-driven frictional ruptures: theory and applications

Alexis Alejandro Sáez Uribe

Fluid-driven frictional ruptures are important in a broad range of subsurface engineering technologies and natural earthquake-related phenomena. Some examples of subsurface operations where borehole fluid injections can induce frictional slip are deep geot ...

EPFL2023

Three-dimensional hydraulic fracture propagation in homogeneous and heterogeneous media

Carlo Peruzzo

Hydraulic fractures are tensile fractures that occur in solid materials due to the natural intrusion or anthropogenic injection of a viscous fluid into a fracture channel. The deliberate creation of hydraulic fractures is part of an industrial technology h ...

EPFL2023

Bounding the localized to ductile transition in porous rocks: implications for geo-reservoirs

Marie Estelle Solange Violay, Gabriel Gérard Dominique Meyer

Porous rocks have long been the focus of intense research driven by their importance in our society as host to our most essential resources (oil, gas, water, geothermal energy, etc), yet their rheology remains poorly understood. With increasing depth, poro ...

2023

Propagation of planar three-dimensional buoyant hydraulic fractures

Andreas Möri

Hydraulic fractures are driven by an internal fluid pressure exceeding the minimum compressive stress, propagating in a direction perpendicular to the latter. This class of tensile fractures has gained interest over the last fifty years due to the developm ...

EPFL2023

Geomechanics for Energy and the Environment: Current Developments

Lyesse Laloui, Roba Houhou

Geomechanics is advancing our understanding of the multi-physical processes encountered in engineering practices involving energy storage and production and environmental protection for which the characterization of the behavior of relevant materials is es ...

2022

Machine learning enhancement of thermal response tests for geothermal potential evaluations at site and regional scales

Lyesse Laloui, Benoît Claude Henri Cousin, Alessandro Francesco Rotta Loria

This study explores and validates a machine learning approach for the practical, effective, and precise prediction of the thermo-physical characteristics that are essential for the analysis and design of shallow geothermal systems, including borehole heat ...

2021

On the effects of fluid pressure variations on rock-mass and fault mechanical behaviour

Corentin Jean-Marie Rémi Noël

In the past 20 years, the growing interest in deep geo-reservoirs for purposes such as carbon storage, waste water disposal, or geothermal energy exploitation have led to large-volume fluid injections into the upper continental crust. These fluid injection ...

EPFL2021

Experimental studies of hydro-mechanical couplings in Enhanced Geothermal Reservoirs

Mateo Alejandro Acosta

Enhanced Geothermal Systems (EGS) allow for worldwide geothermal electricity production. They target deep (3-5 km), fractured rock reservoirs whose permeability is artificially increased through hydraulic stimulations (fluid injections). The injections mod ...

EPFL2020

Hydraulic stimulation of pre-existing discontinuities in tight rocks

Federico Ciardo

Hydraulic stimulation is an engineering technique whose aim is to enhance the permeability of fractured rock masses at depths ranging from one to five kilometers. It consists in the injection of fluid at sufficiently high pressure in order to shear pre-exi ...

EPFL2020

Stress management in the context of induced seismicity in subsurface reservoirs

Barnaby Padraig Fryer

The stress state of the subsurface has been shown to have an influence on a number of key processes. For example, the criticality of the stress state indicates how large stress changes need to be before a fault begins to slip, the mean effective stress con ...

EPFL2020

Mechanical and hydraulic transport properties of transverse-isotropic Gneiss deformed under deep reservoir stress and pressure conditions

Marie Estelle Solange Violay, Mateo Alejandro Acosta

In central Europe, many geo-energy reservoirs have revealed to be hosted in transverse isotropic crystalline rock, where the rock's mechanical and hydraulic transport properties are poorly constrained. Here, we performed triaxial experiments on Cresciano G ...

2020

Effect of Fluid Viscosity on Earthquake Nucleation

Marie Estelle Solange Violay, Chiara Cornelio

Injection of fluids in geo-reservoirs can reduce the effective stresses at depth, lubricating the nearby faults, promoting slip and, potentially, earthquakes. High-viscous fluids are often used during hydraulic fracturing and production phases in geo-reser ...

2020

Extension of Winkler’s solution to non-isothermal conditions for capturing the behaviour of plane geostructures subjected to thermal and mechanical actions

Lyesse Laloui, Qazim Llabjani, Alessandro Francesco Rotta Loria, Jacopo Zannin

Before this study, no analytical models had been made available for describing the behaviour of plane geostructures subjected to thermal and mechanical actions. This knowledge gap notably represented a limitation for investigations about the behaviour of s ...

2020

Dynamic response of a compressible binary fluid mixture

Ignacio Pagonabarraga Mora

Binary fluids are present in a wide variety of systems at microscales, such as microfluidic devices containing drops, fluids with air bubbles trapped in them, and devices designed to mix fluids or to make two fluid substances react. Microfluidics devices a ...

2020

Mineral equilibria and thermodynamic uncertainties in the geothermometrical characterisation of carbonate geothermal systems of low temperature. The case of the Alhama-Jaraba system (Spain)

Javier Reguera Gomez, Maria Pilar Asta Andres

Geothermometrical characterisation of low-temperature, carbonate-evaporitic geothermal systems is usually hampered by the lack of appropriate mineral equilibria to successfully use most of the classical geothermometers and/or by the thermodynamic uncertain ...

2019