Requirements for the development of EGS

Content:

1. Status: what we know/need

2. Identification of Obstacles

3. R+D Requirements

Dr. Th. MégelGEOWATT AG, CH-Zürich

ENGINE Launching Conference, 13-15 th February 06, F-Orléans

Session: How to improve exploitation and cost-effectiveness of geothermal energy

and manage environmental and social impacts?

Status: what we know/need

EGS-PMDAHandbook developed underIEA-GIA, Annex III

Generic project

Index of Suppliers

Collected Experiences

Bibliography

• Principal milestones• Data Matrix: Data requirement• Task Matrix: First point of data need(EXCEL) 

Register of suppliers (EXCEL)

Databases (ACCESS)Information to project documents and data• Fenton Hill • Rosemanowes• Soultz-sous-ForêtsEGS literature database (EndNote)

Project planning

Sources of Know-how

Chapters:

http://www.iea-gia.org/

Identification of Obstacles

Fact 1: R+D activities for EGS since over 35 years.

Obstacles:

1. Financially not attractive ?!

2. Too risky with regard to environmental andsocial impacts ?!

R+D Requirements

Fact 2: Still no commercial EGS power plant worldwide.

Will we have commercial EGS power plants in 35 years?

Identification of Obstacles

Costs Production Productioncosts

Investment costs + Operating costs

€ / year MWh / year € / MWh+

+

R+D Requirements

Minimising Maximising Minimiseduntil

Market(Politics)

€ / MWh<

Maximiseduntil

<

The economical rules are simple...:

Identification of Obstacles

Concept Exploration Development Production Abandonment

Phases of an EGS life cycle

?

Siteselected

Feasibility ofEGS at site

demonstrated

Installations andreservoir ready for

production

Productionlifetime reached

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-investmentfor this site:Deconstruction

Milestones

Identification of Obstacles

Concept phase

Exploration phase

Development/Production/Aban. phase

Data matrix (EGS-PMDA):Information and data required foreach project phase

Identification of Obstacles

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C Exp D Production A

Siteselected

Feasibilityevaluated

Maximising

Minimising

R+D requiredfor...

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C Exp D Production AFeasibilityevaluated

GO - NO GO ?

Identification of Obstacles

High risk phase Low risk phase

Principal obstacle: High risk money is expensive

The GO - NO GO decision must be taken as early as possible !

1. shortening of the high risk phase

2. reduction of the high risk investment

3. limiting impacts (social/ environ.)

R+D required to minimise costs by ...

Identification of Obstacles

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

Pro

du

ctio

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C Exp D Production A

Feasibilityevaluated

GO - NO GO ? Return of investment

Principal need: Production must be stable on a sufficient level to cover all investments and operating costs

1. maximise production

2. guarantee production

R+D required to...

R+D Requirements

Key task: • Technical productivity enhancement• Technical permeability enhancement

near-borehole domain + reservoir domain

Extended, systematic stimulation/enhancement R + D programme

Major problemso far:

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!

• mechanical• chemical• others...new...

!!

for different techiques:

R+D Requirements

Extended, systematic stimulation/enhancement R + D programme

Tasks:

I Stimulation R+D tests in existing boreholes,not necessarily deep!

II Stimulation R+D tests in new boreholes,not necessarily deep!

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

V ...

Methods:

A Identification of physical/chemicalprocesses of permeability enhancement

B Identification of leading parametersfor each stimulation method

C Productivity as a function of leading parameters

D What combination of subsurface parametersdo we find in Europe?

E Which combination of parameters excludesuccessful enhancement?

F Are there limits of permeability enhancementfor given subsurface conditions?

G Can a limited seismic magnitude be guaranteedfor given conditions?

H ...

Conclusions

• 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

If EGS power plants shall become commercial, then...:

Extended, systematic stimulation/enhancement R + D programme