This is an excerpt from EERE Network News, a weekly electronic newsletter.
Geodynamics Proves Viability of Enhanced Geothermal Systems
Geodynamics Limited has claimed success in creating a geothermal reservoir at a geological "hot spot," proving the feasibility of so-called Enhanced Geothermal Systems (EGS). The company's Habanero project in South Australia's Cooper Basin involved injecting high pressure water into a geologic formation where high temperatures were known to exist, thereby fracturing the rock and forming an underground geothermal reservoir. To tap that reservoir required drilling a second nearby well, allowing water to be injected into one of the wells, where it would pass through fractures in the hot rock and be steadily heated until it was extracted again through the second well. In late March, Geodynamics completed a successful flow test using two of its Habanero wells, leading the company to announce that it has successfully achieved its proof of concept. See the EGS page on the DOE Geothermal Technologies Program Web site for an illustration and detailed description of the EGS concept.
Geodynamic's closed-loop testing between two of its wells—Habanero 1 and 3—reached a maximum flow of 15.5 kilograms per second (kg/s), and modeling of the reservoir indicated that at flows of 70 kg/s, it would be capable of generating more than 40 thermal megawatts for 20 years with only a slight drop in temperature. The flow loop test is the result of six years of work, and the next step is to install a pilot power plant that will generate 1 megawatt of power. Geodynamics intends to install that pilot plant by mid-year, providing power to the nearby town of Innamincka. The company plans to follow that with Australia's first commercial-scale geothermal power plant, which should be operating by 2012. See Geodynamic's announcement of its completion of the flow test (PDF 277 KB), which includes an independent contractor report, and the company's accompanying press release (PDF 59 KB). Download Adobe Reader.