Hungary has decided to implement its first geothermal pilot power plant for electricity production. The site chosen is in South-West-Hungary and is positioned on a fractured limestone reservoir. The reservoir’s depth is about 3000m and the temperature is 142oC. Two existing petroleum-prospecting dry holes were chosen to implement a doublet for the geothermal energy supply with a separation of approximately 1000m. The projected flow rate of the circulating water is 5000 m3/d. The lifespan of this production-injection system is one of critical concern to the industry. During a recent pre-feasibility study, an analytic model was developed to determine the propagation of the cooled region between the two wells. In this model, the reservoir is replaced by a plain equivalent fracture with a Hele-Shaw flow. The Hele-Show flow can be viewed as a quasi-potential motion. After applying complex variable functions, a theoretical flow pattern can be determined. The heat transfer between the water and the rock is calculated with a transient overall heat transfer coefficient. The cold front is not obtained as an abrupt temperature drop but, as an extended moving region with a very slight temperature gradient.

Press the Back button in your browser, or search again.

Copyright 2009, Stanford Geothermal Program: Readers who download papers from this site should honor the copyright of the original authors and may not copy or distribute the work further without the permission of the original publisher.