| Title | The Overview of 5-years Study of the EGS Technology Development Using ScCO2 |
|---|---|
| Authors | Amane TERAI, Toshiyuki TOSHA, Takuya TERAOKA, Shoko WATANABE, Taro KABASHIMA, Kenji OSAWA |
| Year | 2026 |
| Conference | World Geothermal Congress |
| Keywords | |
| Abstract | JOGMEC has been conducting a research project of EGS technology development using supercritical carbon dioxide (ScCO2) from 2021 as an innovative geothermal power generation technology toward the goal of 2050 carbon neutral in Japan. This project aims to develop technology to generate electricity using ScCO2 as a heat transfer medium instead of water in areas where a mature hydrothermal system does not exist, including creating an artificial heat exchange layer in a high-temperature area by CO2 fracturing. The idea of using ScCO2 for EGS has been announced since around 2000 (e.g. Brown, 2000; Pruess, 2009) and the previous research show the possibility of ScCO2 to be a better heat transfer medium than water. However, the chemical properties of CO2 were not fully taken into the flow simulation and there is less paper about the experiment and the simulation about mineralization and fracturing using CO2 under the condition of high temperature and high pressure. For the first five years (2021-2025), we have been trying to understand the underlying technology of 3 themes by laboratory experiment, small size field experiment and simulation. The 3 themes are; 1.Overall system design for CO2 geothermal power generation, 2.Artificial geothermal reservoir formation technology using ScCO2 as the fracturing fluid, 3.Technology for understanding CO2 fluid behavior in geothermal reservoirs. In this paper, we describe the major achievements gained through the basic study over first 5-years. |