Note: Intro -- Preface -- Contents -- 1 Thermal Structure of the Earth -- 1.1 Renewable Energies, Global Aspects -- 1.2 Internal Structure of the Earth -- 1.3 Energy Budget of the Planet -- 1.4 Heat Transport and Thermal Parameters -- 1.5 Brief Outline of Methods for Measuring Thermal Parameters -- 2 History of Geothermal Energy Use -- 2.1 Early Utilization of Geothermal Energy -- 2.2 History of Utilization of Geothermal Energy in the Last 150 years -- 3 Geothermal Energy Resources -- 3.1 Energy -- 3.2 Significance of "Renewable" Energies -- 3.3 Status of Geothermal Energy Utilization -- 3.4 Geothermal Energy Sources -- 4 Applications of Geothermal Energy -- 4.1 Near Surface Geothermal Systems -- 4.2 Deep Geothermal Systems -- 4.3 Efficiency of Geothermal Systems -- 4.4 Major Geothermal Fields, High Enthalpy Fields -- 5 Potential Perspectives of Geothermal Energy Utilization -- 6 Geothermal Probes -- 6.1 Planning Principles -- 6.2 Construction of Ground Source Heat Exchangers -- 6.3 Dimensioning and Design of Geothermal Probes -- 6.3.1 Heat Pumps -- 6.3.2 Thermal Parameters and Computer Programs for the System Design of Ground Source Heat Pump Systems -- 6.4 Drilling Methods for Borehole Heat Exchangers -- 6.4.1 Rotary Drilling -- 6.4.2 Down-the-Hole Hammer Methods -- 6.4.3 Concluding Remarks, Technical Drilling Risks -- 6.5 Backfill and Grouting of Geothermal Probes -- 6.6 Construction of Deep Geothermal Probes -- 6.7 Operating Geothermal Probes: Potential Risks, Malfunctions and Damages -- 6.8 Special Systems and Further Developments -- 6.8.1 Geothermal Probe Fields -- 6.8.2 Cooling with Geothermal Probes -- 6.8.3 Combined Solar Thermal: Geothermal Systems -- 6.8.4 Geothermal Probe: Performance and Quality Control -- 6.8.5 Geothermal Probes Operating with Phase Changes -- 7 Geothermal Well Systems -- 7.1 Building Geothermal Well Systems. , 7.2 Chemical Aspects of Two-Well Systems -- 7.3 Thermal Range of Influence, Numerical Models -- 8 Hydrothermal Systems, Geothermal Doublets -- 8.1 Geologic and Tectonic Structure of the Underground -- 8.2 Thermal and Hydraulic Properties of the Target Aquifer -- 8.3 Hydraulic and Thermal Range of Hydrothermal Doublets -- 8.4 Hydrochemistry of Hot Waters from Great Depth -- 8.5 Reservoir-Improving Measures, Efficiency-Boosting Measures, Stimulation -- 8.6 Productivity Risk, Exploration Risk, Economic Efficiency -- 8.6.1 Exploration Risks -- 8.7 Some Site Examples of Hydrothermal Systems -- 8.7.1 High-Enthalpy Hydrothermal Systems -- 8.7.2 Low-Enthalpy Hydrothermal Systems -- 8.7.2.1 Paris Basin (France) -- 8.7.2.2 Bavarian Molasse Basin, Unterhaching (Germany) -- 8.7.2.3 Bruchsal Research Site in the Upper Rhine Rift Valley (Germany) -- 8.8 Project Planning of Hydrothermal Power Systems -- 8.8.1 Phase 1: Preliminary study -- 8.8.2 Phase 2: Feasibility study -- 8.8.3 Phase 3: Exploration -- 8.8.4 Phase 4: Development -- 9 Enhanced-Geothermal-Systems, Hot-Dry-Rock Systems, Deep-Heat-Mining -- 9.1 Techniques, Procedures, Strategies, Aims -- 9.2 Historical Development of the Hydraulic Fracturing Technology, Early HDR Sites -- 9.3 Stimulation Procedures -- 9.4 Experience and Dealing with Micro-Seismicity -- 9.5 Recommendations, Notes -- 10 Environmental Issues Related to Deep Geothermal Systems -- 10.1 Seismicity Related to EGS Projects -- 10.1.1 Induced Earthquakes -- 10.1.2 Quantifying Seismic Events -- 10.1.3 The Basel Incident -- 10.1.4 Observed Seismicity at Other EGS Projects -- 10.1.5 Conclusions and Recommendations Regarding Seismicity Control in Hydrothermal and Petrothermal (EGS) Projects -- 10.2 Interaction Between Geothermal System Operation and the Subsurface -- 10.3 Environmental Issues Related to Surface Installations and Operation. , 11 Drilling Techniques for Deep Wellbores -- 12 Geophysical Methods, Exploration and Analysis -- 12.1 Geophysical Pre-drilling Exploration, Seismic Investigations -- 12.2 Geophysical Well Logging and Data Interpretation -- 13 Testing the Hydraulic Properties of the Drilled Formations -- 13.1 Principles of Hydraulic Testing -- 13.2 Types of Tests, Planning and Implementation, Evaluation Procedures -- 13.3 Tracer Experiments -- 13.4 Temperature Evaluation Methods -- 14 The Chemical Composition of Deep Geothermal Waters and Its Consequences for Planning and Operating a Geothermal Power Plant -- 14.1 Sampling and Laboratory Analyses -- 14.2 Deep Geothermal Waters, Data and Interpretation -- 14.3 Mineral Scales and Materials Corrosion -- References.