Ernst Huenges www.gfzpotsdam.degeothermSan Diego GRC2006 September 12 1

1

• Current status of the EGS Gross Schönebeck
  project on the way to demonstrate sustainable
  brine production from deep sediments of the North
  German basin
• Ernst Huenges, Ali Saadat, Wulf Brandt, Inga
  Moeck, Heinz Holl, Günter Zimmermann, Guido
  Blöcher, Silke Köhler, Björn Legarth, Torsten
  Tischner,
• GeoForschungsZentrum Potsdam (GFZ)

2
(No Transcript)
3
Geology NE German Basin
NE German Basin
Scheck Bayer,1999
Poland Basin
Lamarche et al.,2005
4
Local geology Groß Schönebeck
Moeck et al., 2006
5
Integrated Geophysical Exploration Technologies
for Deep Fractured Geothermal Systems (I-GET)
Berlin
10
0
6
In-situ Geothermal Laboratory Groß Schönebeck
7
In-situ Geothermal Laboratory Groß Schönebeck

• research borehole in sedimentary rocks
• 4.3-km deep, 150 C with stimulated
  reservoir
• drilling 2. well and concept to enhance
  mass-flow rate from the reservoir using a
  doublet
• demonstration sustainable production with
  longterm circulation
• geothermal power production in the North German
  Basin

8
productivity enhancement by hydraulic fracturing

• creating zone of increased permeability
• enlarging apparent wellbore radius
• by-pass skin
• improve inflow conditions

9
Operations overview

• open hole fracs with packer(injecting 100 m³
  gel, 7 to proppants, cidric acid)

• open hole waterfrac (injecting
  11,575 m³ (pH5- acid) conditioned water)

• preparation 2. well
• injection test reservoir modelling
• EU-tender for drilling services
• Mining rights procedure
• Design of drilling program setup
  of the drillsite

10
waterfrac Nov/Dec 2003
? HP triplex pumps ? 80 l/s bei 500 bar ? 4000 kW
? wellbore completion ? frac string installation
? 1500 m³ storage ? acidization ? filter systems
11
production test Groß Schönebeck 1.12.03

• productivity index 14 m³/(h MPa) _at_
  fracture opening/closure pressure
• enhanced from 0.6 m³/(h MPa)

12
Injection pressure temperature around the wells
30 a
Production well
Injection well
thermal water loop with 75 m³/h
13
Ongoing Drill 2. well and realise the doublet

• 2006/2007
• Drill 2.well (directional, balanced)
• multifracturing
• Commitment of the energy provider Vattenfall
• 1. Primar productivity for 750 kW-power plant2.
  Demonstration of sustainibility (circulation
  test)

Directional drilling concept 2.well
14
Start of drilling 2.wellin Groß Schönebeck
15
Status 2. well in Groß Schönebeck
Status 2006 September 9th, 3827 m soon entering
the reservoir
16
Forthcoming tests in Groß Schönebeck
17
Step 2 Installation of the geothermal power plant
2007Demonstration of geothermal power production
(partner in industry Vattenfall Europe AG) -
demonstration - optimisation of the
processes- improving efficiency
18
Conclusions

• Experiences in a case study of a deep sedimentary
  reservoir with several hydraulic fracture
  treatmentsgt evaluation of a EGS reservoir
  created by hydraulic fracturing in sandstone and
  volcanic rocks
• Concept based on parallel fracs and
  transmissibility within the formationgt
  reservoir performance (not shown fracture
  mapping, geochemistry)
• on the way geophysical methods (I-GET funded by
  EU)
• Groß Schönebeck site since 2001, with 10 MW
  thermal power _at_ 140 C expected after drilling
  and enhancing the second borehole
• Groß Schönebeck research test site to develop
  deep sedimentary geothermal reservoirs