Steam Production Activities, Utilization Factor, Cost Reduction, Ogiri Geothermal Power Plant Japan, Kirishima Geothermal Field Japan

Abstract

The Ogiri Geothermal Power Plant commenced the commercial operation on March 1, 1996. It is the joint project between the Kyushu Electric Power Co., Inc. and the Nittetsu Kagoshima Geothermal Co., Ltd., which are responsible for the power generation and the steam production, respectively. Concerning the cost reduction of geothermal power generation as one of the most important factors for the geothermal development, attention should be paid to the drilling costs of the steam wells and the improvement in utilization factor of geothermal power plant facilities. While the author submitted a report titled ëImprovement of Success Ratio of Drilling Wellsí to the WGC 1995, the present report is to make a supplementary statement from a point of view of the cost reduction of drilling. The Ogiri Geothermal Power Plant has been enjoying a satisfactory and stable work with the cumulative utilization factor of 94.84 % (against the national average of 76.1 % in 1989) for 39 months (as of the end of May 1999) since the beginning of the commercial operation. The report will not only give an outline of the situation of operation mainly of the steam producing division, the improvement in utilization factor of the plant facilities, and the cost reduction, but mention the future prospect.