Articles

Induced seismicity in EGS reservoir: the creep route

Observations in enhanced geothermal system (EGS) reservoirs of induced seismicity and slow aseismic slip ruptures on related faults suggest a close link between the two phenomena.

Authors: Jean Schmittbuhl, Olivier Lengliné, François Cornet, Nicolas Cuenot and Albert Genter

Hydrochemical properties of deep carbonate aquifers in the SW German Molasse basin

The Upper Jurassic (Malm) limestone and the Middle Triassic Muschelkalk limestone 18 are the major thermal aquifers in the southwest German alpine foreland. The aquifers 19 are of interest for production of ge...

Authors: Ingrid Stober

Discussion on `Spectral analysis of aeromagnetic data for geothermal energy investigation of Ikogosi Warm Spring - Ekiti State, southwestern Nigeria’

The recent paper by Abraham et al. (2014) `Spectral analysis of aeromagnetic data for geothermal energy investigation of Ikogosi Warm Spring - Ekiti State, southwestern Nigeria’ applied spectral analysis in th...

Authors: Levi Ikechukwu Nwankwo

The significance of hydrothermal alteration zones for the mechanical behavior of a geothermal reservoir

The occurrence of hydrothermally altered zones is a commonly observed phenomenon in brittle rock. The dissolution and transformation of primary minerals and the precipitation of secondary minerals affect rocks...

Authors: Carola Meller and Thomas Kohl

A simplified model for the estimation of life-cycle greenhouse gas emissions of enhanced geothermal systems

The development of `enhanced geothermal systems' (EGS), designed to extract energy from deep low-enthalpy reservoirs, is opening new scenarios of growth for the whole geothermal sector. A relevant tool to esti...

Authors: Martino Lacirignola, Bechara Hage Meany, Pierryves Padey and Isabelle Blanc

Physical property relationships of the Rotokawa Andesite, a significant geothermal reservoir rock in the Taupo Volcanic Zone, New Zealand

Geothermal systems are commonly hosted in highly altered and fractured rock. As a result, the relationships between physical properties such as strength and permeability can be complex. Understanding such prop...

Authors: Paul A Siratovich, Michael J Heap, Marlène C Villenueve, James W Cole and Thierry Reuschlé

Mapping the low enthalpy geothermal potential of shallow Quaternary aquifers in Finland

EU member states have concluded an agreement that renewable energy will cover 20% of the total energy production by 2020. To achieve this target, it is essential to investigate all possibilities for renewable ...

Authors: Teppo Arola, Lari Eskola, Jukka Hellen and Kirsti Korkka-Niemi

Inferring the in situ stress regime in deep sediments: an example from the Bruchsal geothermal site

Knowledge of the ambient state of stress is of crucial importance for understanding tectonic processes and an important parameter in reservoir engineering. In the framework of the 2,500-m deep geothermal proje...

Authors: Jörg Meixner, Eva Schill, Emmanuel Gaucher and Thomas Kohl

Spectral analysis of aeromagnetic data for geothermal energy investigation of Ikogosi Warm Spring - Ekiti State, southwestern Nigeria

Aeromagnetic data of the Ikogosi warm spring region was used to calculate the basal depth of the magnetic layer (Curie point depth) in the region. The warm spring issues from a crossing of fractures from a met...

Authors: Ema Michael Abraham, Kolawole Muideen Lawal, Amobi Chigozie Ekwe, Owens Alile, Kehinde Ayofe Murana and Aminu Ahmed Lawal

High-heat-producing granites of East Dharwar Craton around Gugi, Karnataka, and their possible influence on the evolution of Rajapur thermal springs, Deccan Volcanic Province, India

The thermal springs of Rajapur situated along the west coast of Maharashtra and parts of high-heat-generating granites of Gugi in Karnataka (India) seem to be genetically related. The present investigation inv...

Authors: Hemant K Singh, Yadvendra Kumar, Dornadula Chandrasekharam, Trupti Gurav and Banambar Singh

Thermal effect of a borehole thermal energy store on the subsurface

The thermal effect on the subsurface of a large borehole thermal energy store (BTES) has been investigated by coupling measured rock properties with an enhanced FEFLOW simulation.

Authors: Philipp Mielke, Dan Bauer, Sebastian Homuth, Annette E Götz and Ingo Sass

Thermodynamic pre-determination of power generation potential in geothermal low-temperature applications

Small capacity, low temperature, geothermal heat sources provide significant opportunities for distributed, small scale power generation. Project definitions and pre-dimensioning however require advanced therm...

Authors: Henrik Öhman and Per Lundqvist

Hydrochemistry and geothermometry of an Albian aquifer from Oued Righ region in northeastern Algerian Sahara

The area of Oued Righ is one of the important geothermal areas in northeastern Algerian Sahara. It is characterized by a hot arid climate with intense dryness and very high evaporation rates. These various cli...

Authors: Warda Chaib and Nacer Kherici

A systematic review of enhanced (or engineered) geothermal systems: past, present and future

Enhanced (or engineered) geothermal systems (EGS) have evolved from the hot dry rock concept, implemented for the first time at Fenton Hill in 1977. This paper systematically reviews all of the EGS projects wo...

Authors: Katrin Breede, Khatia Dzebisashvili, Xiaolei Liu and Gioia Falcone

Three-dimensional thermal sensitivity analysis of cooling of a magma chamber in the Los Azufres geothermal field, Michoacán, Mexico

We present three-dimensional simulation of cooling of 63 models of a magma chamber in the Los Azufres geothermal field by varying the top of the chamber depth between 5 and 9 km (centroid from about 7 to 13 km...

Authors: Surendra P Verma and Efraín Gómez-Arias

Thermal response test numerical modeling using a dynamic simulator

Borehole heat exchangers are a growing technology in the area of house/building air conditioning, most of all in northern Europe.

Authors: Sara Focaccia

Performance analysis and working fluid selection for geothermal energy-powered organic Rankine-vapor compression air conditioning

To utilize geothermal energy from hot springs, an organic Rankine cycle/vapor compression cycle (ORC/VCC) system was employed for air conditioning and a thermodynamic model was developed.

Authors: Xianbiao Bu, Lingbao Wang and Huashan Li

Geothermal Energy: a glimpse at the state of the field and an introduction to the journal

Authors: Olaf Kolditz, Leslie A Jakobs, Ernst Huenges and Thomas Kohl