Drilling of hot-dry-rock geothermal-energy extraction well EE-3
The drilling of EE-3, the production well of the hot dry rock geothermal energy-extraction engineering system at the Fenton Hill site, was finished August 25, 1981. EE-3 was designed to be directionally drilled in the inclined reservoir section to be parallel to and spaced vertically 370 m (1200 ft) above EE-2, the injection well, which was drilled at 35/sup 0/ to the vertical. The reservoir heat transfer area will be formed by creating and extending several vertical parallel hydraulic fractures from EE-2 to EE-3. EE-3 required precision directional drilling because the borehole trajectory had to be drilled within specified tolerances with respect to EE-2. Well EE-2 was drilled with a packed (stiff) bottom-hole assembly that held the 35/sup 0/ inclination, but permitted the borehole to turn in azimuth. Directional drilling experience in EE-2 provided the basis to optimize the directional trajectory of EE-3 to within the desired tolerances. The EE-3 well was drilled into hot granite reservoir rock to total depth of 370 m (1200 ft) parallel and above EE-2 at a measured (drill-string) depth of 4.25 km (13,933 ft), with a maximum lateral deviation of about 60 m (180 ft). A bottom-hole static temperature of 280/sup 0/C (550/sup 0/F) is estimated. Two severe drill-pipe twist-offs extended the drilling time of EE-3 to 461 days. These, and other drilling problems, are recorded and solution approaches are discussed. Drilling costs of EE-2/EE-3 are shown to be comparable to commercial drilling of hydrothermal wells and to the US Department of Energy sponsored geothermal projects when these cost trends are extrapolated to 4.5-km (15,000-ft) depths.
- Research Organization:
- Los Alamos National Lab., NM (USA)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 6858700
- Report Number(s):
- LA-9512-HDR; ON: DE83001954
- Country of Publication:
- United States
- Language:
- English
Similar Records
Precision directional drilling of hot dry rock geothermal production well EE-3
Directional drilling operations Hot Dry Rock well EE-2
Related Subjects
150901* -- Geothermal Engineering-- Drilling Technology & Well Hardware
COMMINUTION
COST
DIRECTIONAL DRILLING
DRILL PIPES
DRILLING
DRILLING EQUIPMENT
DRILLING FLUIDS
ENERGY SYSTEMS
EQUIPMENT
FEDERAL REGION VI
FLUIDS
FRACTURING
GEOTHERMAL SYSTEMS
GEOTHERMAL WELLS
Geothermal Legacy
HEAT EXTRACTION
HOT-DRY-ROCK SYSTEMS
HYDRAULIC FRACTURING
NEW MEXICO
NORTH AMERICA
PIPES
USA
WELLS