Landolt-Börnstein - Group VIII Advanced Materials and Technologies
8.2 Geothermal energy resources
This chapter talks about geothermal energy resources and provides an estimate of their global potential. Geothermal energy comprises the heat stored both in the solid rock and in the fluids of its voids, and distinguishes it from heat stored in surface water bodies such as rivers, lakes and oceans. Four types of geothermal resources are usually distinguished: hydrothermal, geopressured, hot dry rock (HDR) and magma. It is customary to classify energy resources according to the scheme proposed initially by McKelvey for mineral resources. The classification accounts for the varying degrees of geological assurance and economic feasibility. The chapter provide the definitions of geothermal resource categories and their estimated global potential. Accessible geothermal resource base by region is also tabulated.