Geothermal resources of the USSR and prospects for their practical use

Abstract

Planning of geological exploration for thermal waters and exploitation of geothermal fields should be preceded by: — establishment of bulk possible reserves of thermal waters all over the country — rating of technical-economical efficiency of thermal waters utilization and their share in the fuel-power budget of any particular district. Studies of main principles governing the area extent of thermal waters all over USSR territory; together with the estimation of their heat potential, mineralization and composition, have allowed us to distinguish over ten promising territories of thermal waters for practical utilization. Among them are the platform regions, where the thermal waters are in stratified position, as well as folded areas, where fissurevein type hot waters are found. Within these promising regions possible reserves have been estimated for thermal waters with a mineralization not exceeding 35 g/l and a temperature above 40°C, and associated to thermal aquifers occurring at a depth not exceeding 3000 m (for fissure-vein type waters no deeper than 300–500 m). These reserves seem to be over 250 m 3/sec. A primary condition for a paying exploitation of thermal resources to the end of geothermal heat supply (as a main kind consumption) to be obtained is a combined utilization of thermal waters, together with adequately selected and arranged consumers, application and working through of most progressive technical problems favouring and increasing the operation effect of heat potential. The mass introduction of geothermal heat supply should be preceded by large-scale experimental construction and checking of various heat-supply schemes on pilot-exploitational plants. This testing should be carried out within a wide range of hydrothermal, heat-engineering and climatic conditions. Some power-engineering characteristics are suggested (a geothermal heat-supply system efficiency factor, ratio of wells utilization), which allow us to characterize the efficiency of a particular devised scheme.