日本地球惑星科学連合2019年大会

講演情報

[E] ポスター発表

セッション記号 S (固体地球科学) » S-TT 計測技術・研究手法

[S-TT42] Recent Advances in Exploration Geophysics 2019

2019年5月26日(日) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 8ホール)

コンビーナ:三ケ田 均(京都大学大学院工学研究科)、飯尾 能久(京都大学防災研究所)、島 伸和(神戸大学大学院理学研究科惑星学専攻)、武川 順一(京都大学大学院工学研究科)

[STT42-P05] 超臨界地熱環境下における人工貯留層の造成による地熱資源開発の実現可能性

*植田 樹1三ケ田 均1武川 順一1 (1.京都大学)

キーワード:超臨界地熱発電、数値シミュレーション、差分法

Japan has many volcanoes and large potential of geothermal energies. However, since 1996, the construction of large-scale geothermal plants in Japan has been stopped, and the amount of electricity generated by the geothermal plants decreased by about 30 percent compared to the peak time in 1997. Existing geothermal energy development has mainly targeted shallow geothermal resources. However, shallow geothermal resources are eccentrically located so we can generate power at narrow area and obtain the limited amount of energy. On the other hand, geothermal power generation using supercritical water is expected to increase power output with one power plant than the conventional geothermal power plants. Moreover, by constructing artificial reservoir, it becomes possible to introduce it in wide area and it is expected to contribute to reduction of development and attenuation risk. However, the feasibility of the geothermal power plants using supercritical water has not been fully investigated yet. In this research, we focus on artificial geothermal reservoir under supercritical environment, and quantitatively investigate its feasibility using numerical simulations. Specifically, artificial supercritical geothermal power generation with a downhole coaxial heat exchanger and a single U-shaped pipe method are considered as the heat exchanger method. We solve the unsteady thermal conduction problem using the finite-difference method with various flow rate and injection pressure conditions. As the result of numerical simulation, it was confirmed that in the case of both the double pipe system and the single U-shaped pipe, it is possible to extract supercritical water. Moreover, it was also found that high-performance heat insulating tubes are required for the inner pipe or the production well in either the double pipe type or the single U-shaped pipe type.