The Japanese islands are located on the Pacific Ring of Fire and are blessed with geothermal resources. In spite of this, the use of geothermal energy in Japan is still limited, mainly because of legal, social and socio-economic barriers. The three major barriers are; 1) regulations on natural parks, 2) cost and development risk, and 3) social acceptance. After the nuclear accident in 2011, however, the government changed several regulations on natural parks and put new economic incentives to promote geothermal energy utilization. The government also started several actions to raise social acceptance for geothermal development. Given such support from the government, private sectors moved toward geothermal development drastically.
The total installed capacity of geothermal power plants in Japan was approximately 555 MWe at the end of 2019. The annual electricity production in FY 2017 was about 2,409 GWh (Yasukawa et al., 2020).
Figure 1: Location of geothermal power plants.
Ground-Source Heat Pump
The installation of GSHP in Japan has been rapidly increasing these years, although the total number is still rather small. The total number of facilities that use GSHPs was 2,662 and the installed capacity of all the GSHPs was 163 MWt at the end of FY2017. The annual energy use was 765 TJ in FY2017 (Yasukawa et al., 2020).
Figure 2: Installation of GSHP in Japan
Figure 3: The number of installations of GSHP for different facilities
The majority of the direct use of geothermal resources in Japan is bathing by mostly utilizing natural hot spring or artificially drilled hot spring wells. Other major direct uses are for space heating, greenhouse, fish farming, agricultural drying, and snow melting (Yasukawa et al., 2020).
Table 2: Direct use of geothermal water in Japan
Kasumi Yasukawa, Nobuyasu Nishikawa, Masakatsu Sasada and Tadahiko Okumura (2020), Country Update of Japan, Proceedings of World Geothermal Congress 2020, Reykjavik, Iceland, 7p.
Thermal and Nuclear Power Engineering Society (TENPES) (2018), Current status of geothermal power generation in Japan 2017, 144p (in Japanese).