HEAT EXTRACTION EXPERIMENT AT HIJIORI TEST SITE

Abstract

NEDO (New Energy and Industrial Technology Development Organization) conducted a research on development of hot dry rock (HDR) that is a future geothermal resource of energy. As a verification of heat extraction capacity of artificial geothermal reservoir of HDR, a heat extraction experiment for long term was planed three years ago. Preparation, surface instruments, reservoir modeling, prediction of heat extraction behavior, a design of experiment and so on, took three years and the actual experiment of heat extraction was ready to be started. It was started from the late of November and it will last for two years. Though we met unexpected high injection impedance at the beginning and stop of production for 6-days caused by well logging, heat extraction test still continues now. Injection rate is 60t/h and injection pressure is about 8MPa Hot water and steam are produced from wells successfully and production temperature is around 180 deg. C at wellhead. Recovery is about 50% and thermal output is up to 9MW.