In an announcement today, Japanese INPEX Corp. reported that it will conduct short-term flow tests to gauge the capacity of exploratory wells it has drilled in the Oyasu region of Akita Prefecture, Japan in partnership with Idemitsu Kosan Co., Ltd. and Mitsui Oil Exploration Co., Ltd., with which it has jointly pursued commercialization studies on geothermal power generation since 2011.
The short-term flow tests will be conducted on two exploratory wells drilled during the current fiscal year. The tests will evaluate production capacity based on a constant flow over a 1~2 week period using wells similar in size to actual production wells. Through these experiments, the companies will verify details concerning well production capacity (volume of steam), underground temperatures, chemical composition of geothermal fluids, water permeability in the vicinity of the well and other matters.
The exploratory wells are similar in size to actual production or injection wells, and are used to conduct production and injection tests over several weeks.
The State 1 of the project was completed in the financial year of 2011, with superficial surveys (ground-level geological surveys, gravitational exploration, electromagnetic exploration, etc.)
Stage 2 was completed in the financial year of 2017 with Drilling survey, building roads for equipment transportation, etc. – Drilling exploratory wells to study geological structures, underground temperatures and water permeability. Furthermore a monitoring survey of the hot spring was conducted, including monitoring hot spring temperatures, yields, and chemical composition at nearby hot spring wells.
INPEX and its partners will now conduct the third stage of studies including (1) production and injection experiments, (2) reservoir capacity assessments, (3) environmental impact studies, etc. from FY2018 to FY2021, as well as conduct short-term Flow Tests of Exploratory well.
Source: company release (pdf)