Japan Geoscience Union Meeting 2022

Presentation information

[J] Oral

M (Multidisciplinary and Interdisciplinary) » M-ZZ Others

[M-ZZ48] Renewable energy and earth science

Mon. May 23, 2022 3:30 PM - 5:00 PM 103 (International Conference Hall, Makuhari Messe)

convener:Hideaki Ohtake(National Institute of Advanced Industrial Science and Technology), convener:Daisuke Nohara(Central Research Institute of Electric Power Industry), convener:Teruhisa Shimada(Graduate School of Science and Technology, Hirosaki University), convener:Fumichika Uno(Nihon University, College of Humanities and Sciences), Chairperson:Hideaki Ohtake(National Institute of Advanced Industrial Science and Technology)

3:30 PM - 3:45 PM

[MZZ48-06] Technical Issues for Increasing Geothermal Power Generation in Japan

*Yota Suzuki1, Hiroshi Asanuma1 (1.National Institute of Advanced Industrial Science and Technology)

Keywords:Geothermal, Supercritical, Resource assessment, AI, Hot spring, Monitoring

The Agency for Natural Resources and Energy has set the estimated amount of geothermal power generation capacity to be introduced in Japan at 1,400–1,550 MW in 2030, but the installed capacity of geothermal power generation was only 593 MW at the end of March 2020; therefore, a significant increase in the amount of geothermal power generation is essential to achieve the target. In this presentation, we discuss the technical issues necessary to increase the amount of geothermal power generation in Japan, focusing on the following three themes: next-generation technology development, geothermal resource assessment, and social acceptability.

Next Generation Technology Development
To significantly increase the amount of geothermal power generation, it is important to steadily promote conventional geothermal development as well as research innovative geothermal development technologies. Supercritical geothermal systems, which originate from the subduction of oceanic plates, are located at or below the brittle-ductile transition (BDT) region and contain supercritical fluids (T > 374 °C and P > 22.1 MPa for pure water and T > 406 °C and P > 29.8 MPa for seawater), which are expected to significantly increase the amount of geothermal power generation and reduce CO2 emissions. In addition, supercritical geothermal power generation technology is considered to be an important innovative technology to significantly reduce greenhouse gas emissions in the "Green Growth Strategy through Achieving Carbon Neutrality in 2050". In this presentation, the current status and future issues related to the development of supercritical geothermal power generation technology in Japan are discussed.

Geothermal Resource Assessment
Muraoka et al. (2008) developed Japan's first GIS-based geothermal potential map and estimated a shallow hydrothermal resource of 23,470 MW, which is important for steam-flash geothermal power generation. This value is the third largest in the world, which is why Japan is regarded as a geothermally resource-rich country. The geothermal potential map in Japan has provided many insights, such as that 81.9% of geothermal resources are located in the Special Protection Areas of national parks, but it does not always provide the necessary information for new geothermal development. In this presentation, we outline the geothermal potential map for Japan and discuss the necessity of updating it.

Social acceptability
Japan is not only a geothermal resource-rich country but also a hot spring resource-rich country. Japan's hot spring industry is the largest market in the world, and forms the basis of the domestic tourism industry. Because of this background, the evaluation of the impact of geothermal development on the surrounding hot springs is considered important in Japan, and there have been cases in the past where development was halted due to a lack of understanding from local hot spring operators. Continuous observation and analysis of hot spring quality data through monitoring is effective for estimating the hydraulic characteristics of hot springs and promoting the understanding of hot spring operators. In this presentation, we discuss the social acceptability of geothermal development, focusing on the importance of hot spring monitoring and technical issues.