Comparison of two hot dry rock geothermal reservoirs

Conference · Tue Jan 01 00:00:00 EST 1980

OSTI ID:6718668

Murphy, H D; Tester, J W; Potter, R M

Two hot dry rock (HDR) geothermal energy reservoirs were created by hydraulic fracturing of granite at 2.7 to 3.0 km (9000 to 10,000 ft) at the Fenton Hill site, near the Valles Caldera in northern New Mexico. Both reservoirs are research reservoirs, in the sense that both are fairly small, generally yielding 5 MWt or less, and are intended to serve as the basic building blocks of commercial-sized reservoirs, consisting of 10 to 15 similar fractures that would yield approximately 35 MWt over a 10 to 20 yr period. Both research reservoirs were created in the same well-pair, with energy extraction well number 1 (EE-1) serving as the injection well, and geothermal test well number 2 (GT-2) serving as the extraction, or production, well. The first reservoir was created in the low permeability host rock by fracturing EE-1 at a depth of 2.75 km (9020 ft) where the indigenous temperature was 185/sup 0/C (364/sup 0/F). A second, larger reservoir was formed by extending a small, existing fracture at 2.93 km (9620 ft) in the injection well about 100 m deeper and 10/sup 0/C hotter than the first reservoir. The resulting large fracture propagated upward to about 2.6 km (8600 ft) and appeared to Rave an inlet-to-outlet spacing of 300m (1000 ft), more then three times that of the first fracture. Comparisons are made with the first reservoir. Evaluation of the new reservoir was accomplished in two steps: (1) with a 23-day heat extraction experiment that began October 23, 1979, and (2) a second, longer-term heat extraction experiment still in progress, which as of November 25, 1980 has been in effect for 260 days. The results of this current experiment are compared with earlier experiments.

• Research Organization: Los Alamos Scientific Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6718668
• Report Number(s): LA-UR-80-3496; CONF-801233-2
• Resource Relation: Conference: 6. annual workshop on geothermal reservoir engineering, Stanford, CA, USA, 16 Dec 1980
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
HOT-DRY-ROCK SYSTEMS
COMPARATIVE EVALUATIONS
CRACK PROPAGATION
HEAT EXTRACTION
GEOTHERMAL WELLS
GRANITES
HYDRAULIC FRACTURING
INJECTION WELLS
PERMEABILITY
COMMINUTION
FRACTURING
GEOTHERMAL SYSTEMS
IGNEOUS ROCKS
PLUTONIC ROCKS
ROCKS
WELLS
Geothermal Legacy
150906* - Geothermal Engineering- Reservoir Stimulation & Extraction Technology