The development of high-temperature geothermal fields with supercritical conditions are emerging as a new hot topic in various parts of the world since a significantly higher power output seems feasible with less drilling required. However, superhot geothermal systems (SHGS) with temperatures over 350°C require novel and innovative exploration and exploitation concepts, adapted to the special conditions encountered at depth. Therefore, considerable research efforts are necessary for (i) an improved understanding of the conditions at depth (e.g., fractures, rock properties, stress field, chemistry, risks) at a sufficient confidence level, and (ii) the development of novel concepts for a successful development of such resources, which may differ from well-established methods currently used for conventional hydrothermal systems. This includes advancements in drilling technologies, well integrity, installation materials, and well logging, as well as development of risk mitigation and management concepts adapted for higher temperatures and pressures. In this context, the application of Engineered Geothermal Systems (EGS) technologies may be part of the solution.
The aim of this special issue is to merge experiences gained in past and ongoing international projects (e.g., IDDP, DEEPEGS, DESCRAMBLE, GEMex, JBBP, NEWGEN and others) with a major focus on the development of concepts for the use of high-temperature geothermal fields. This special issue attempts to (i) present novel ideas and possible solutions, and (ii) pose future research questions to the geothermal community to make use of a powerful resource at great depth in a sustainable manner.
Lead Guest Editor
Egbert Jolie, GFZ German Research Centre for Geosciences
Guest Editors
Hiroshi Asanuma, AIST, Japan
Guðmundur Ómar Friðleifsson, IDDP, Iceland