METHOD OF EXTRACTING AND UTILIZING GEOTHERMAL ENERGY AND GEOTHERMAL PLANT

摘要

PURPOSE: To raise extracting efficiency of geothermal energy by forming penetrating passages in the bottom zone of a vertical bore hole dug deep into the ground, filling a heat-conducting substance in the passages and inserting a supply line and a return line for a heat transmission medium to flow in the vertical bore hole. CONSTITUTION: After a vertical bore hole 3 of a depth of above 1500 m is dug in a rack base 1, penetrating passages 7 formed by cracks and the like are formed surrounding the rock in a bottom zone 5 of the vertical bore hole 3. The penetrating passages 7 are formed by a blowing or the like in the bottom zone 5. A substance S with high heat-conduction is forced into the bottom zone 5. The substance S is embedded in the penetrating passages 7 and coated on the inner wall of the bottom zone 5. After that, a casing 9 with a closed end is inserted into the vertical bore hole 3 with the lower portion thereof thermally connected to a compound M including a thermal conducting substance S in proportion of appropriate amount. A return line 11 is inserted into the casing 9 to allow a heat transmission medium W to flow, so that geothermal energy can be absorbed and extracted to ground surface.