permeability enhancement at habanero egs...
TRANSCRIPT
Permeability Enhancement at
Habanero EGS Project
PROGRESS UPDATE FOR IEA-GIA
SEPTEMBER 2013
Robert Hogarth
3
Habanero Project Update
• Granite temperature of 241°C at 4,130m depth;
consistent with earlier well results
• Open flow tests achieved rates of ~38 kg/s
• Indications of >40 kg/s � Much higher than
previous wells flow tests of 25-30 kg/s
• Pilot Plant commissioned April 30; results meeting
or exceeding expectations in all key areas
• Circulating 17.6 kg/s in closed-loop (10 Sep 2013)
• Flowing temperature of 211°C and increasing
• Power station generating power to run brine pump,
auxiliaries and camp – excess capacity, but no load
available
Over the past 12 months Geodynamics has achieved
significant progress in its Habanero EGS Project
culminating in the commissioning of the 1 MWe Pilot
Plant in April.
Habanero 4 seismicity
4
Plan view with
Habanero 1 at 0,0
Colour indicates time
of event;
Size indicates event
magnitude;
Seismicity from earlier
stimulations shown as
grey dots
5
Habanero fault within seismic cloud
View from the north showing seismic cloud, top granite and wells
Habanero reservoir is an overthrust fault, dipping ~10° to the west
Truncated to the east by a reverse boundary fault
Stimulations of Habanero Producers
• Habanero 3 (drilled into seismic cloud from H01)–Short (local) stimulation with 2.2 ML water (no additives)
–Generated 475 seismic events around the well
–Productivity tripled post-stimulation
– k.h improved from ~1 D.m to ~3 D.m and skin reduced
• Habanero 4 (drilled into seismic cloud from H01)–Short (local) stimulation with 2.5 ML water (no additives)
–Generated 1,900+ seismic events around the well
–Productivity doubled post-stimulation
– k.h improved from ~5 D.m to ~10 D.m and skin reduced to zero
6
Stimulations of Habanero Injectors
• Habanero 1–Two massive stimulations with total 37 ML water (some NaCl for weight)
–Generated 40,000+ seismic events extending up to 1,950 m from well
– Injectivity remained low throughout at ~ 1 kg/s/MPa
–Steady improvement with continued injection in closed-loop mode
–Most likely explanation is mud damage in fault zone
• Habanero 4–One short and one massive stimulation with total 36 ML water
– Injectivity ~ 4.5 kg/s/MPa which is 3 times the best achieved at H01
–Generated 27,000+ seismic events extending up to 1,550 m from well
–Shows benefit of managing bottom hole pressure during drilling to avoid
mud losses into fractures/faults
8
Lessons learned at Habanero
• Habanero reservoir is a fault which is critically stressed and prone to
slip, triggered by stimulation
• The fault was already hydraulically conductive, water saturated,
overpressured, and critically stressed when H01 was drilled
• Mud losses into the fault system were extremely damaging and must
be avoided
• Small volume (local) stimulations have delivered significant
productivity improvements
• Large volume (extended) stimulations have created a seismic cloud
of ~ 4 km2 area
10