Technologies for Deep Geothermal Energy

SpringerBriefs in earth system sciences, pp. 29–73

Abstract

Geothermal energy is currently harvested mainly from high-enthalpy resources, i.e. from resources located in regions with favorable geothermal conditions. Most of them are hydrothermal systems and so-called conventional geothermal reservoirs, such as the oldest geothermal field in Lardarello, Italy. However, technological innovation led to an increased exploration and development of low- to medium-enthalpy resources in hot sedimentary aquifers and petrothermal reservoirs. Especially the latter enables geothermal heat use in less favorable regions, thus circumventing geographical limitations. Firstly, this chapter introduces the typical development steps for geothermal projects and associated technologies and methods. Furthermore, it addresses specific requirements for petrothermal reservoirs, providing an overview of unconventional technologies, equipment, and methods, as well as related research and innovation (R&I) activities. For example, it covers innovative drilling technologies suitable for deep hard-rock formations. In addition, the development of petrothermal reservoirs would not be possible without the enhanced geothermal system (EGS) technology that aims at increasing the reservoir permeability by stimulation techniques. We introduce methods of developing petrothermal reservoirs deploying EGS and give an overview of existing large-scale EGS projects in Europe. Here, a main research focus lies on the development of advanced stimulation techniques for minimizing the risk of induced seismicity.

Authors 3

1. Johanna Fink corresponding Aachen Institute for Applied Geophysics and Geothermal Energy

   RWTH Aachen University

   Affiliation as printed

   Institute for Applied Geophysics and Geothermal Energy, RWTH Aachen University, Aachen, Germany

2. Elisa Heim Aachen Institute for Applied Geophysics and Geothermal Energy

   RWTH Aachen University

   Affiliation as printed

   Institute for Applied Geophysics and Geothermal Energy, RWTH Aachen University, Aachen, Germany

3. Norbert Klitzsch Aachen Institute for Applied Geophysics and Geothermal Energy

   RWTH Aachen University

   Affiliation as printed

   Institute for Applied Geophysics and Geothermal Energy, RWTH Aachen University, Aachen, Germany