Classification of geothermal heat extraction technologies

This article deals with the issue of developing a new classification of geothermal energy extraction technologies by generalizing and analyzing existing theoretical and experimental studies in this field. The existing approaches to the classification of geothermal systems are considered, distinguishing hydrothermal and petrothermal technologies, as well as their application depending on different conditions of their use. The paper emphasizes the importance of introducing new technologies and updating the classification of the existing ones to achieve sustainable development of the Russian energy system. It is emphasized that geothermal energy is an environmentally friendly resource, geothermal systems are scalable, and geothermal energy belongs to inexhaustible energy resources. The focus is on creating a systematic approach to classification that takes into account the diversity of technologies and their specific characteristics. The proposed classification includes five levels covering the heat sources, location of the extraction zone, depth of the heat source, principle of implementation and type of heat source extraction. The paper discusses advantages and disadvantages of different systems. The study evaluated and ranked the technologies according to the criteria of cost, environmental safety, reliability and potential for scaling. The proposed classification and evaluation criteria will make it possible to systematically describe and compare different types of technologies for geothermal energy extraction, which can help in selecting the most appropriate technology for specific regions and conditions. Based on the study, it is found that geothermal thermosyphons with natural circulation of the working medium are a rational choice when applied in petrothermal circulation systems