Requirements for the development of EGS
Session:
How to improve exploitation and cost-effectiveness of geothermal energy
and manage environmental and social impacts?
Content:
1. Status: what we know/need
2. Identification of Obstacles
3. R+D Requirements
Dr. Th. Mégel
GEOWATT AG, CH-Zürich
ENGINE Launching Conference,
13-15 th February 06, F-Orléans
Status: what we know/need
EGS-PMDA
Handbook developed under
IEA-GIA, Annex III
Chapters:
Project planning
Generic project
Index of Suppliers
• Principal milestones
• Data Matrix: Data requirement
• Task Matrix: First point of data need
(EXCEL)
Register of suppliers (EXCEL)
Sources of Know-how
http://www.iea-gia.org/
Collected Experiences
Databases (ACCESS)
Information to project documents and data
• Fenton Hill
• Rosemanowes
• Soultz-sous-Forêts
Bibliography
EGS literature database (EndNote)
Identification of Obstacles
Fact 1:
R+D activities for EGS since over 35 years.
Fact 2:
Still no commercial EGS power plant worldwide.
Will we have commercial EGS power plants in 35 years?
Obstacles:
1.
Financially not attractive ?!
2.
Too risky with regard to environmental and
social impacts ?!
R+D Requirements
Identification of Obstacles
The economical rules are simple...:
Costs
Production
Production
costs
MWh / year
€ / MWh
+
<
Market
(Politics)
Investment costs + Operating costs
€ / year
Minimising
+
Maximising
R+D Requirements
Minimised
until
<
€ / MWh
Maximised
until
Identification of Obstacles
Phases of an EGS life cycle
Concept
Exploration
Development
Production
Abandonment
?
General regional
planning:
• technical
• political
• financial
• environmental
• Pilot borehole
• Stimulation tests
• Production modelling
• Inj./Prod boreholes
• Intensive stimulation
• Production tests
• Surface installations
• Power/Heat production:
• Maintenance
If no re-investment
for this site:
Deconstruction
Milestones
Site
selected
Feasibility of
EGS at site
demonstrated
Installations and
reservoir ready for
production
Production
lifetime reached
Identification of Obstacles
Concept phase
Exploration phase
Data matrix (EGS-PMDA):
Information and data required for
each project phase
Development/Production/Aban. phase
Identification of Obstacles
C
Exp
D
Production
A
R+D required
for...
14
Investment
Investement
Minimising
12
10
8
6
4
2
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
Production
Production
Year
Maximising
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
Year
Site
selected
Feasibility
evaluated
Identification of Obstacles
C
Exp
D
Production
A
Feasibility
evaluated
14
GO - NO GO ?
Investment
Investement
12
10
8
6
4
2
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
Year
High risk phase
Principal obstacle:
High risk money is expensive
The GO - NO GO decision must be
taken as early as possible !
Low risk phase
R+D required to minimise costs by ...
1.
shortening of the high risk phase
2.
reduction of the high risk investment
3.
limiting impacts (social/ environ.)
Identification of Obstacles
Exp
D
Production
A
Production
C
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
Year
Feasibility
evaluated
GO - NO GO ?
Principal need:
Production must be stable on a
sufficient level to cover all
investments and operating costs
Return of investment
R+D required to...
1.
maximise production
2.
guarantee production
R+D Requirements
• Technical productivity enhancement
• Technical permeability enhancement
Key task:
!
Major problem
so far:
near-borehole domain +
reservoir domain
At all EGS R+D projects the success was always
coupled on an expected productivity for future production.
Hence the systematic development of stimulation techniques
was difficult. But this is what is needed!
Extended, systematic stimulation/enhancement R + D programme
for different techiques:
• mechanical
• chemical
• others...new...
!
R+D Requirements
Extended, systematic stimulation/enhancement R + D programme
Tasks:
Methods:
A Identification of physical/chemical
processes of permeability enhancement
I
Stimulation R+D tests in existing boreholes,
not necessarily deep!
B Identification of leading parameters
for each stimulation method
II
Stimulation R+D tests in new boreholes,
not necessarily deep!
C Productivity as a function of leading parameters
III
Laboratory test
•
•
•
•
•
different rock types
different stress regimes
different methods (mechanical, chemical)
different fracture fillings
sites with no limits for massive tests !
IV
Professionally managed, firmly concerted
D What combination of subsurface parameters
do we find in Europe?
E Which combination of parameters exclude
successful enhancement?
F Are there limits of permeability enhancement
for given subsurface conditions?
G Can a limited seismic magnitude be guaranteed
for given conditions?
H ...
V ...
Conclusions
If EGS power plants shall become commercial, then...:
•
Production must cover all capital costs
•
Either the production is such that an extended exploration phase
- including a lot of failures - can be financed, or the production can be
predicted early in a projects life cycle
•
Production must become predictable for conditions at a given site
•
Production is based on stimulation/enhancement techniques
•
Therefore:
Enhanced permeability for given conditions and technique used
must become predictable
Extended, systematic stimulation/enhancement R + D programme