Flow Test At Fenton Hill HDR Geothermal Area (Brown, 1994)

Exploration Activity: Flow Test At Fenton Hill HDR Geothermal Area (Brown, 1994)

Exploration Activity Details
Location	Fenton Hill HDR Geothermal Area
Exploration Technique	Flow Test
Activity Date	1992 - 1993
Usefulness	useful
DOE-funding	Unknown

Exploration Basis

The LTFT of the Phase II reservoir was conducted in two phases, for 16 weeks from April to July in 1992 and again for 8 weeks concluding in May of 1993.

Notes

Two reservoirs were created to test the feasibility of extracting a thermal resource from hot rocks that lack in-situ geothermal fluids. The second, deeper Phase II reservoir was created by pressure-stimulation and hydraulic fracturing of jointed granitic rocks at a depth of 3500 m with an average temperature or 235°C. This reservoir was flow tested in 1986 during the Initial Closed-Loop Flow Test (ICFT), and again from 1992 to 1993 during the Long-Term Flow Test (LTFT). During the first phase of the LTFT, the Phase II reservoir was operated at approximately 6.8 L/s injection rate and 10 MPa backpressure. Between the two phases of the LTFT, a 6 week Interim Flow Test (IFT) was conducted at backpressures of 10 MPa and lower injection rates 4.3 L/s (22 MPa), in addition to two months of testing in November and December of 1992 where the reservoir was operated under injection rates of 7.1 L/s and backpressures of 12 MPa. The second phase of the LTFT was conducted using injection rates of 7.3 L/s and backpressures of 15 MPa. Injection pressures were only varied during the IFT-all other flow tests were run using 27 MPa injection pressure. The temperature of the injected water used during each test was approximately 18°C. During the first phase of the LTFT, waters were produced from well EE-2 at flow rates of 5.7 L/s and temperatures of 183°C. Under the reduced injection pressures of the IFT, production flow rates and temperatures were 3.9 L/s and 165°C, respectively. Further increasing the backpressure to 15 MPa resulted in a return to production flow rates of 5.7 L/s at temperatures of 183°C. During the second phase of the LTFT (the highest backpressure test), flow rates were 5.3 L/s at temperatures of 177°C.

References

Donald W. Brown (1994) Summary of Recent Flow Testing of the Fenton Hill HDR Reservoir

Donald W Brown (2009) Hot Dry Rock Geothermal Energy- Important Lessons From Fenton Hill

Timothy J. Callahan (1996) Reservoir Investigations on the Hot Dry Rock Geothermal System, Fenton Hill, New Mexico- Tracer Test Results

Donald Brown, Robert DuTeaux (1997) Three Principal Results from Recent Fenton Hill Flow Testing

Hugh Murphy, Donald W Brown, Reinhard Jung, Isao Matsunaga, Roger Parker (1999) Hydraulics and Well Testing of Engineered Geothermal Reservoirs

Donald W Brown, Robert DuTeaux, Paul Kruger, Daniel Swenson, Tsutomu Yamaguchi (1999) Fluid Circulation and Heat Extraction from Engineered Geothermal Reservoirs

Additional References