The Cost Effectiveness of Fracture Stimulation in Increasing the Flow from Geothermal Wells

Abstract

The cost effectiveness of fracture stimulation at The Geysers, the Iqwrial Valley, and other geothermal resource areas in the United States vas studied using GEOCOM, a conputer code for analyzing the ivpact of completion activities on the life-cycle costs of geothermal vells. Technologies for fracturing the reservoir near the wellbore involve the creation of a pressure pulse in the wellbore by rncaps of either hydraulic or explosive force. The cost of a single fracture stimulation job can vary frorr $50,000 to over $500,000, with a typical cost of around $300,000. The code shows that additional flow achieved by fracture stimulation must exceed 10,OCO pounc)s per hour for each $100,000 invested in stipulation in order for a fracture treatment to te cost effective. In some reservoirs, this additional flow must be as great as 30,000 pounds per hour. The cost effectiveness of fracturing has not yet been demonstrated in the field. The Geothermal Well Stimulation Program achieved an overall average of about 10,000 pounds per hour for each $100,000 invested.