Global geothermal electricity potentials: A technical, economic, and thermal renewability assessment

Geothermal energy can play an important role in dispatchable power generation. However, no detailed global energy potential exists. This study calculates the global energy potential for enhanced geothermal power and determines its impact on the energy supply of countries. In this work, the first detailed land eligibility analysis for enhanced geothermal power is conducted, three reservoir models (Gringarten, Volume Method and Sustainable Approach) are compared. The results show that land eligibility is highly dependent on local conditions and varies from <5 to 72 % eligibility with a global average of 25 %. The Gringarten model is the only one to reach realistic production rates and thus economically feasible production plants. Global hotspots for geothermal power below 5 ct€/kWhel are found in 17 specific countries in the developing world, as well as in Russia, Iceland, Hungary and Japan. Below 10 ct€/kWhel, potential can be found throughout the Americas, Africa and Southeast Asia. Therefore, deep geothermal energy can be a cheap and reliable source of electricity for developing countries. However, its use for developing countries depends on the cost reduction for geothermal drilling by the developed nations. For countries such as USA, Japan, China, geothermal power can only partially supply their energy systems.