This document summarizes key learnings from various studies and theses related to geothermal energy development. It notes that geothermal projects have different economics than oil and gas due to their localized nature. Reducing costs and optimizing production are important to lower break-even prices. Innovation and knowledge sharing are also crucial to advance geothermal energy. Several challenges were identified, including well integrity, interference management, seismic risk analysis, and permitting processes.

1. The learning curve in
geothermal operations:
Finding silver bullets to
combat the challenges
Hydreco Geomec
Barbara Cox
December 4, 2019
Silver
bullets
December 4:
Santa Barbara day

2. The energy transition:
from global commodity to local solutions
Global Oil transportation
Oil&Gas Storable
Local heat networks
Heat and electricity not so storable

3. This makes a geothermal project different:
• A geothermal project can only be realised if local demand and supply match
• A geothermal project often requires a tailor made solution with many stakeholders
The energy transition:
from global commodity to local solutions
Geothermie Alliantie Zuid-Holland

4. Economics:
CAPEX+OPEX: 2 wells required for a geothermal doublet
Revenues:
The energy transition:
from global commodity to local solutions
1 m3 oil
€380
10MWh
1 m3 hot water
€1+ €2 subsidies = €3
0,050MWh
Note: 300m3/h can be produced
Break even price reduction (lower cost, higher production):
Upscaling, repetition (portfolio and play-based)
Efficiency and standardization
Innovation and knowledge sharing
• New exploration strategies
• Shallow- and Ultra Deep Geothermal
• HT-ATES

5. Hydreco Geomec: geothermal development by
combining global operational knowledge with
local project development expertise
Current play-based scope
of HG’s concessions
Repeat potential#
Exploration Feasibility Preparation Realisation
& testing
Start-up Work-over Clean up
Project development
Production
(sub)surface management
Project management Plant management
Project
management
Engineering and change management
VG documentation and risk management
Licenses and environmental management
Supplier and contract management
Document and data management
Long term committed operator
Geothermal development is core business
Financial participation in projects
In house experience and expertise (team ~30 professionals)
Involved in all fases of the project: development, realisation, and long term
operations & management
Active contribution to maturing the geothermal sector

6. Resources & services from the hydrocarbon industry
Reservoir Simulation for Play-based Development of Low Enthalpy
Geothermal Resources: Application to the Delft Sandstone
MSc Thesis Duncan Perkins
October 2019
Different economics for geothermal development: cost reduction required
Geothermal Tools available (DoubletCalc, DoubletCalc2D, gemech.xls)
What’s the value of using basic versus advanced tools?
Temperature change versus time curves
which demonstrate the influence of
thermal recharge from non-reservoir
lithologies on breakthrough time.
3D porosity model viewed from the South.
Red represents 25% porosity whilst pink is
1% porosity
Comparison between an ideal conceptual
meander belt system (top) and the
distribution of porosity in the grid
(bottom)
DoubletCalc2D
(T after 15yrs)

7. The importance of chemistry
Injectivity reduction in geothermal wells:
Investigating the causes
MSc Thesis Tim van der Hulst
August 2019
Examples of carbonate scale (left) and sulfate scale (right). Geothermal Museum Lardello, Italy Example of sampling at a geothermal installation
• Correlation between microbial growth and injectivity reduction
• Corrosion inhibitor enhances microbial growth
• Biocide prevents microbial growth
• Also, scaling is possible in small amounts before(calcite) and after (barite) the heat exchanger.
• Additionally, the quantity of suspended solids is not problematic high. At the same time, it is also
not proven to be sufficiently low to exclude TSS as possible cause of injectivity reduction.
Avoid use of corrosion inhibitors in wells
Corrosion
Injectivity reduction

8. Well integrity: for sustainable production of
sustainable energy
GRE lined well design
HydrecoGeomec-Veegeo-WEP
2019

9. Seismic Risk Analysis for geothermal activities?
MSc Thesis Bas Nieuwstad
January 2020
Geothermal Seismic Risk Analysis
methods exist, but do not take all
the physics into account
New method required: EZK will start
a study in 2020
In the meantime (2019) Bas
Nieuwstad has worked out an
analytical Geothermal SRA tool
with/for HydrecoGeomec
SodM
Qcon/IF
TNO
Qcon/IF

10. Well interference: laws & permitting
Pressure and Temperature Interference
for Geothermal Projects in
Dense Production Areas
MSc Thesis Patrick Reinhard
September 2019
Conclusions chapter 8 MSc thesis Patrick Reinhard:
Policy measures for P&T interference poorly defined;
reservoir modelling specs defined
Extraction license boundary defined by well distance only
dP of 1 bar and dT of 1C allowed at boundary: not realistic
No policy to mitigate injection pressure exceedance in
case of interference
Gradient that defines max allowable injection pressure
should be customized for different geological settings
In general: Challenges on law & permitting:
Based on mining law
Permitting process is often on the critical path
Geothermal law & permitting process are being changed

11. Main take-aways
Geothermal energy is not a commodity; economics are different than in the hydrocarbon industry
Geothermal project development is a local activity and often complex with many stakeholders
Reduction of the break-even-price in geothermal developments requires lowering costs and optimizing production
Innovation and knowledge sharing play a key role in making geothermal energy a viable option with a significant
contribution into the sustainable energy mix: Delft University of Technology can play an important role