1. Dr. Pri Utami
Geothermal Research Centre
Faculty of Engineering
Gadjah Mada University
Jalan Grafika 2, Yogyakarta 55281, Indonesia
Geothermal Energy in Indonesia & Western Pacific Region:
Scientific and Technological Challenges for Development
2. TALK OUTLINE
Introduction to Geothermal Energy
High-temperature Geothermal Systems in
Western Pacific Region
Tectonic settings
Natural characteristics
Changes in time and space
Challenges for Exploration and Development
Update on R&D and Capacity Building
UGM Milestones
3. What is geothermal ?
Heat energy from the Earth
Geothermal System
A general term that describes natural
heat transfer within a confined volume
of the Earth's crust where heat is
transported from a “heat source” to a
“heat sink,” usually the free surface.
6. Map of geothermal sites of Indonesia. Total potential of > 20,000 MW
(40% of world total potential), scattered in 250 locations
7. The type of geothermal system that is economically most feasible for development in
Indonesia is where magmatic intrusions are emplaced high enough in the crust that
they induce the convective circulation of groundwater
There are other types of geothermal system (a-magmatic) such as those occurring due
to heat sweep through deep-reaching fractures, or deep basin brines, but these are too
cool, too deep, or too saline to allow the economic generation of electricity at this time
in Indonesia
9. (Adapted from Corbett & Leach, 1994)
Hydrothermal system
A type of geothermal system where heat transfers from a heat source
(often a cooling pluton) to the surface by “free convection,” involving
meteoric fluids with or without traces of magmatic fluids.
Liquids discharged at or near the surface are replenished by meteoric
water derived from the outside (“recharge”) that is drawn in by the
rising fluids.
10. 1. ENVIRONMENT-FRIENDLY
Geothermal power
generations discharge
very significantly much
lower pollutant
compared to that of
fossil fuels.
ADVANTAGES OF GEOTHERMAL ENERGY
(cyclic, high-temperature, magmatic related systems)
CO2 emission (Fridleifsson, 2000)
H2S emission (Hunt, 2001)
11. Geothermal fluid whose heat has
been extracted is re-injected into
the deep reservoir, such that no
thermal fluid is let to contaminate
the surface/near surface
environment.
12. 2. RENEWABLE
Its heat source and recharge fluids are both naturally renewed.
3. SUSTAINABLE
Geothermal systems are long-lived (Western Pacific: ~300 - 500 ka)
and the produced thermal fluids is naturally recharged.
There is engineering strategy to ensure their sustainability, i.e., re-
injection of the extracted fluids for maintaining the heat and mass
balance of the geothermal reservoir.
13. 4. INDIGENEOUS
5. RELIABLE
Being renewable, sustainable
and indigenous therefore,
geothermal energy is reliable,
because its supply is
INDEPENDENT from season
and energy market situation
outside the country.
Geothermal is an indigeneous energy, meaning that it can only be directly utilized in
place, and can not be transported elsewhere before being converted into electricity.
Being indigenous energy resource, its development must be prioritized in order to
elevate the prosperity to their surrounding community.
(Illustration by W. Dimwani, 2001)
14. With the increasing demand of energy in one hand and the
shortage of fossil energy resources in another, we are now
facing a challenge to the increase utilization of renewable
energy, including geothermal, to ensure our energy security.
Geothermal energy development requires a continuous effort
for ensuring sustainable cultivation of the resource.
Consequently, we have to accelerate our human resource
capacity building as well as activities in Research and
Development (R&D) in geothermal.
EXPERTISE MATTERS !
15. GENERAL MODEL – High Temperature Geothermal System in Western Pacific
Historically inactive volcano, spatially associated with active volcano(es)
High-relief terrain; long lateral outflows
Upflow often associated with magmatic fluid conduits
Complex fluid flow patterns
(Utami, 2011)
17. Natural Changes of Geothermal System in Time and Space
(adapted from Browne, 1995)
18. System Notable change(s) – Indicator(s) Related event – Timing
LAHENDONG
1. Shift of the focus of activity – Shift of the focus of the shallowest
occurrence of the mineral geothermometers
Eruption centered at Lake Linau – (?)
(Utami et al, 2007) 2. Cooling – ∆(T mineral – T measured) Incursion of groundwater – since LGM (?)
TIWI
1. Discharge and recharge cycle:
a. Deep fluid discharge – silica sinter
b. Upwelling and boiling – (Quartz ± adularia ± epidote ± pyrite ±
base metal sulfide)
c. Heating of recharge fluids – (calcite and anhydrite)
Tectonic and subvolcanic intrusion – (?)
(Moore et al, 2000)
2. Renewed heating – thermal modeling
Igneous intrusion – 10 to 50 ka
3. Incursion of sea water – sea water component in fluid inclusions Regional subsidence along Bicol Arc – (?)
KAMOJANG
Change from liquid to vapor-dominated –
a. Altering fluid VS present-day fluid phases
b. Reduced permeability due to mineral deposition
Unknown
(Utami, 2000)
KARAHA –
T. BODAS
Change from liquid to vapor-dominated –
a. Field-wide deposition of chalcedony
b. Fluid inclusions microthermometry
Rapid depressurisation due to flank
collapse of Mt. Galunggung – 4.2 ka
(Moore et al, 2004)
ULUMBU 1. Local heating and cooling – ∆(Th fluid incl – T measured) Unknown
(Utami et al, 1996)
2. Reopening of fluid channels – changes in optical properties of
minerals Deformation – (?)
Examples of Natural Changes in Some Geothermal Systems
in Western Pacific (exctracted from Utami, 2011)
19. EXPLORATION STAGE
Challenges: resource confidence (high-T & permeability, benign fluid
chemistry), reduction of exploration risk and cost !
Exploration design
Execution
Data interpretation
Exploration drilling
Field delineation
(Photograph by W. Warmada, 2012)
20. EXPLORATION STAGE
Facing the challenges – The power of
3G!
Geological Surveys
To map geologic features and thermal
manifestations
Geochemistry Surveys
To sample and characterize the
surface fluid and to interpret the
subsurface temperatures, process and
flow paths
Geophysical Exploration
To identify heat sources and
permeability structure
Resource assessment
Well targeting
Reservoir characterization
Environmental baseline
Pre-commissioning micro-seismicity,
groundwater quality, ground
deformation, surface manifestations
21. DEVELOPMENT STAGE
Challenges:
Correct understanding on thermal, chemical and hydrological
structures and behavior of reservoir
Correct design and construction of surface facilities
(Courtesy of GNS Sciene, 2011)
(Courtesy PT PGE, 2012)
22. DEVELOPMENT STAGE
Facing the challenges:
Rig geology
petrology & mineralogy of cores and drill cuttings, assessment of
reservoir temperature, permeability, reservoir fluid chemistry
Borehole Imaging
interpretation & integration of borehole image with wireline data,
lithology and drilling data
3-D Geological Modelling
comprehensive modelling of field geology
Reservoir Simulation
reservoir dynamic under fluid withdrawal and re-injection
Experimental Geochemistry
laboratory and computer-based simulation studies of mineral
saturation & scaling
Surface Facility Design & Construction
well, pipelines, power station, condensers, etc
23. PRODUCTION STAGE
Challenges:
Ensure the sustainability of energy production
Improved effectiveness
Mitigation of environmental impact
Facing the challenges: Resource management
Photograph: courtesy of PT. Geo Dipa Energy (2010)
24. RESEARCH & DEVELOPMENT
Multidisciplinary scientific research programs to support
environmentally sustainable growth of geothermal resource
Exploration and utilization of deep (>> 3 km) high temperature
resources
Development of new ideas and innovative tools
Exploration & extraction of valuable geothermal by-products
minerals
Biodiversty and ecology research to assist management of
geothermal ecosystems
Development of field management protocols
Development of community partnership
Building economic and policy framework that support
geothermal development
Development of of international partnership for Research &
Development and capacity buliding
25. HUMAN RESOURCE CAPACITY BUILDING
Formal training in geothermal geoscience & technology at universities
Specialized training for geothermal industry staff
Geothermal induction for Government staff & policy makers
Geothermal “training the trainers”
Geothermal education for everyone !
