Wyborn, D. (2010) Update of Development of the Geothermal Field in the Granite at Innamincka, South Australia. In: Proceedings World Geothermal Congress 2010. International Geothermal Association:.
Full text not available from this repository.Abstract
Geodynamics Limited is developing a geothermal field in unusual geological conditions using the principles of stimulation and circulation currently advocated for Enhanced Geothermal Systems (EGS). A granitic body of about 1000 km2 is located beneath sedimentary rocks 3.5 to 4 km thick. High heat flow and high temperature gradients in the sedimentary rocks have long been established over the granite. The granite is elongated meridionally and is about 50 km by 20 km. To date three areas within the central part of the granite have been explored each about 10km apart. These three areas have been named the Habanero, Jolokia and Savina geothermal developments. Each of the developments is characterised by the presence of natural fractures within the granite with high fluid overpressures manifesting in the five wells drilled so far at surface with a value around 34 MPa. The cause, extent and significance of this regionally extensive overpressure will be discussed. The fracture networks discovered and enhanced by stimulation will be described and a general crustal model of fracture development proposed. The overall aim is to build geothermal power stations as modules spread throughout the area with one station every 4 km2 . Each power station will likely be based on nine wells, 5 production wells and 4 injection wells, with a down-hole well spacing of about 1 km. The wells for each module could be drilled from the one drill pad located beside the power station. The potential to build several hundred power stations of this module size exists, however an initial commercial project is expected to provide around 50 MWe net based on projected flow rates of 70-100 kg/sec and wellhead temperatures of 240-270ºC at each production well. At full development this would amount to around 12,500 MWe potential for the granite with extraction of stored heat down to a depth of 5 km.
| Item Type: | Book Section |
|---|---|
| Uncontrolled Keywords: | Enhanced geothermal system, EGS, granite, stimulation, overthrust stress, overpressures, Habanero, Innamincka. |
| Subjects: | Methodology > Other-additional study Region > Australia Inducing technology > Geothermal energy production |
| Project: | SHEER project > COOPER BASIN: geothermal energy injection experiment |