Resource evaluation of global geothermal energy and the development obstacles

Abstract

According to the technically mining depth of 5 km, the global recoverable geothermal resource extent reaches up to 3.4×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">15</sup> toe, of which, the economically recoverable resource extent reaches 1.19×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sup> toe in the future 40~50 years, equivalent to about 10 times of global annual total primary energy supply. Nevertheless, the low temperature geothermal resources which feature with high development costs occupy the majority, while the high temperature ones are merely 1.9×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">9</sup> toe. Currently, the percentage of geothermal energy in world energy consumption structure is still quite low, equal to only 0.1%, far lower than that of other types of renewable energy such as solar, wind and biomass. In this paper, the geothermal resources were evaluated, and the obstacles in the process of exploitation and development were analyzed, drawing the conclusion that geothermal energy would possibly become a type of “complement” energy rather than “mainstream” energy.