Proceedings World Geothermal Congress 2010
Bali, Indonesia, 25-29 April 2010

The IEA Geothermal Implementing AgreementInternational Efforts to Promote Global Sustainable Geothermal Development andHelp Mitigate Climate Change
M. A. Mongillo, C. J. Bromley and L. Rybach
IEA-GIA Secretariat, GNS Science, Wairakei Research Centre, Private Bag 2000, Taupo, New Zealandmongillom@reap.org.nz

Keywords: IEA, GIA, international cooperation,
sustainable use, environmental issues, EGS, advanced
drilling, direct use, climate changemanner, including: by convening international workshops
on special topics like induced seismicity and sustainability,
by attempting to determine the global development
potential of geothermal energy (conventional, EGS, etc.)
and estimating the contribution it could make towards the
mitigation of climate change (useful as input for the IPCC
2010 renewable energy report), by producing a
Geothermics Special Issue on Sustainability (2009); and by
participating in international renewable energy conferences
and workshops to raise awareness of geothermal energy andeducate the public, government and finance decision
makers, etc.

ABSTRACTThe Geothermal Implementing Agreement (GIA) provides
a flexible and powerful framework for international
cooperation on geothermal research and technology under
the auspices of the International Energy Agency (IEA). It
connects national and industry programmes for exploration,
development and utilization of geothermal resources andestablishes direct cooperative links among experts in theparticipating countries, industries and organizations, thus
helping increase effectiveness. The GIA’s activities arechiefly directed towards the coordination of national andindustry geothermal programmes, with joint participation ofmembers on specific studies. Emphasis is on sharing of
information, developing techniques and best practices, andproducing and disseminating authoritative information.

The IEA-GIA, now well into its 3rd 5-year term and 12th
year of operation, is experiencing significant growth inmembership, having nearly doubled in the past 3 years, andas of May 2009, with 19 members, including: 12 countries(Australia, France, Germany, Iceland, Italy, Japan, Mexico,
New Zealand, Republic of Korea, Spain, Switzerland,
United States), the EC, 4 industries (Geodynamics, GreenRock Energy, ORME Jeotermal, Ormat Technologies) and2 national organizations (CanGEA and Geothermal Group[APPA]).

Current IEA scenarios indicate that unless governments
implement energy saving and renewable energy options,energy security problems and a sharp increase in CO2emissions with related significant climate change effects arelikely. The IEA recently extended the mandate of the GIA
for a 3rd 5-year term (to 2012), and the IEA-GIA embraced
these challenges in its new 3rd term mission: to promotesustainable use of geothermal energy worldwide by
improving existing and developing new technologies torender exploitable the vast and widespread global
geothermal resources, facilitating the transfer of knowhow, providing high quality information and widely
communicating geothermal energy’s strategic, economicand environmental benefits, and thereby contribute to themitigation of climate change. To accomplish this mission,
the GIA is concentrating its current efforts in four major
areas, pursued in the following Annexes: I- Environmental
Impacts of Geothermal Energy Development, II- Enhanced
Geothermal Systems, III- Advanced Geothermal DrillingTechniques and VIII- Direct Use of Geothermal Energy.
GIA’s activities within these topics have grownsignificantly in the past few years with the addition of:
induced seismicity studies associated with EGS reservoir
development/production; investigation of sustainable use
strategies; development of economic guidelines for EGS
reservoir economic models; development of recommended
procedures to create, test and evaluate EGS parameters, anddevelopment of new forms for geographic display of dataon the internet.

The current global energy scene and geothermal’s potential
contribution are outlined; brief reviews of the IEA and the
GIA operation and structure are presented; and the GIA’s
current activities and achievements for supporting
sustainable geothermal development and thereby aiding the
mitigation of climate change are described. Comments on
the GIA’s future plans are also included.
1. INTRODUCTION
This paper provides a major update and amplification of the
IEA-GIA paper presented at the WGC 2005 (Mongillo etal., 2005) and other recent papers by Bromley et al. (2008)
and Mongillo and Rybach (2007). More details about the
IEA and the recent work of the IEA-GIA can be found in
the GIA 2002-2007 End of Term Report (IEA-GIA EoT,
2006), Strategic Plan for 2007-2012 (IEA-GIA SP, 2006)
and in the comprehensive IEA-GIA annual reports available
on the IEA-GIA website. Note that all website addresses
are included in the Reference section.
2. CURRENT GLOBAL ENERGY SCENE
The growth in global demand for energy is expected tocontinue well into the future, with fossil fuel likely toremain the dominant providing source. The IEA has
recently examined several energy utilization and production
scenarios (IEA, 2007; 2008a; 2008b) in attempts to forecast
the situation to 2030, and beyond. The Reference Scenario,
which assumes the continuation of current (as of mid-2008)
government policies and measures, indicates that the total
global primary energy need will grow by 45% between
2006 (11,740 Mtoe [492 EJth]) and 2030, with demandreaching 17,010 million tonnes of oil equivalent (Mtoe)

Geothermal is gaining a growing recognition as one of the
major renewable energy options, with vast worldwide
potential and ability to make a significant contribution. As
a result, worldwide geothermal development is now in a
rapid state of growth. The IEA-GIA is increasing its efforts
to support and help accelerate this growth in a sustainable1Mongillo, Bromley and Rybach[712 EJth]; and the fossil fuel contribution reducing slightly
from 80.9% to 80%. Though it seems that there will be
sufficient fossil fuel to meet the 2030 demand, production
will be controlled by fewer countries, many of which will
be located in “unstable” parts of the world, thus causing
energy security problems. Further, energy-related CO2
emissions will increase from 28 Gt in 2006 to 41 Gt in
2030, an increase of 45%; with total greenhouse gas
emissions (GHG) increasing by 35%, from 44 billion
tonnes (Gt) CO2-equivalent (CO2-eq) in 2005 to 60 Gt CO2eq in 2030; leading to significant climate change effects.
These global energy trends are socially, economically andenvironmentally unsustainable.

thereby increasing technical and economic potentials.
Consequently, there are considerable uncertainties in
estimating worldwide geothermal resource potentials, andfuture revisions are likely as more information and newtechnologies become available.
In 2005, Stefansson (2005) estimated the most likely
worldwide total technical potential for geothermal resources
located along tectonic plate boundaries and near volcanic
hot spots to be about 6.5 TWth (205 EJth/yr), about 40% of
the 2006 worldwide average annual consumption. Of thistotal, hydrothermal resources capable of development forelectricity generation using conventional methods (T > 130°C) made up about 240 GWe (6.5 EJe/yr, or 65 EJth/yr),assuming a 10% electrical conversion efficiency. The
remaining 4.4 TWhth (140 EJth/yr), comprise lower
temperature resources (T ≤ 130 °C) considered usefulmainly for direct heat applications.
Incorporating
approximations for as yet hidden/unidentified resources
increases these estimates by factors of 5-10 (ibid.). In
addition, with current conversion efficiencies increasing,and now ranging up to 20%, power generation potentials
are increasing.

Urgent and strong action is needed to curb the GHG
emissions growth and resulting rise in global temperatures
predicted in the Reference Scenario (GHG concentration of
1,000 ppm and temperature increase of 6 °C relative to preindustrial levels, by the end of the century). The IEA has
developed two alternative climate-based scenarios tostabilize GHG concentrations at 550 ppm (550 Policy
Scenario) and 450 ppm (450 Policy Scenario) CO2-eq,
resulting in a 50% chance of restricting global temperature
increases to about 3 °C and 2 °C, respectively (ibid.). The
total global primary energy demand in 2030 reaches 15,500
Mtoe (32% increase relative to 2006) for the 550 Scenario,
and 14,400 Mtoe (23% increase) for the 450 Policy
Scenario. The CO2 and total GHG emissions in both ofthese scenarios are significantly less in 2030 than in the
Reference Scenario, vis. energy-related CO2 emissions:32.9 Gt for 550 Policy Scenario and 25.7 Gt for the 450
Policy Scenario; and total GHG emissions: 48.2 Gt for the
550 Policy Scenario and 39.3 Gt for the 450 Policy
Scenario. However, both of these climate-based scenarios
require major efficiency gains; CO2 capture and storage(CCS) deployment; a major decrease in the contribution offossil fuels, to be replaced by nuclear and renewables; aswell as considerable public and private RD&D spending.

In 2007, the worldwide geothermal installed power capacity
was ~10 GWe, distributed across 24 countries (Bertani,2007); with > 56.8 TWh generated (IEA-GIA AP, 2008).
Since the present installed capacity amounts to only 4% of
the estimated total global technically feasible potential of
240 GWe of identified hydrothermal resources (~0.5% if
estimates of as yet hidden/unidentified resources areincluded), there is certainly potential for a large increase inconventional (hydrothermal) geothermal development in
the future to meet growing demand for renewable energy inthe tectonically or volcanically active regions. In fact,
Fridleifsson et al. (2008) have recently estimated that by
2050, installed geothermal capacity from hydrothermal
resources could reach some 70 GWe, a 600% increase on
the 2007 value.

Awareness of these possible outcomes, and the knowledge
that energy-related CO2 emissions comprise >65% of total
global GHG emissions, provides a very strong incentive for
expanding the use of clean, renewable energy resources.
However, provision of such huge quantities of affordable,
reliable and clean energy presents an enormous challenge.
We are now truly at a global energy supply and climatechange crossroads, which only international cooperation
can overcome.

The total direct use installed capacity at the end of 2007
was estimated to be about 35,570 MWth, with a total
thermal energy usage of about 329,270 TJ/yr (IEA-GIA AP,
2008.). In 2007, an estimated 1.6 million geothermal heatpumps (GHPs) were installed in more than 30 countries,
and contributed > 19,000 MWth of capacity and > 105,000
TJ/yr utilization (ibid.). As for power generation, thepotential for increased direct use is huge, with only ~0.25%
of most likely direct use technical potential (140 EJth/yr)
currently used. Recent likely-case scenario estimates of
future direct use indicate that by 2050, the total use could
increase to 5.1 EJth/yr, with a GHP contribution of some 4.2
EJth/yr [83%] (Fridleifsson et al., 2008). The dominanceand expected significant growth in GHP use arises fromtheir ability to be used for both heating and cooling almost
anywhere on the earth’s surface.

3. GLOBAL GEOTHERMAL POTENTIAL AND
CURENT USE
Among the renewable energy options, geothermal resources
have the potential to contribute significantly towards
alleviating the world’s energy-climate predicament.
Geothermal resources essentially consist of the heat stored
beneath the earth’s surface and discharging from it. The
main sources for geothermal energy are the heat flow fromthe earth’s core and mantle (~40%), and that generated by
the gradual decay of radioactive isotopes in the earth’s crust(~60%); which together result in an average terrestrial heatflow rate of 44 TWth (1,400 EJ/yr). This natural heat flowrate is nearly three times the 2006 worldwide total primaryenergy use, 492 EJth (136,600 TWhth) (IEA, 2008c).
Though it is clear that the world’s geothermal heat
resources are enormous and ubiquitous, the fact that they
are, in the main, “hidden from view” (underground), makes
it difficult to accurately determine potentials on a global
basis.
This uncertainty is accentuated because thetechnologies used to develop geothermal resources are
evolving, extending capabilities and reducing costs, andIn addition to the abovementioned hydrothermal resources,
there are several other potential significant geothermal
sources capable of power generation and direct heat use,
including: 1) the binary generation from the utilization of
the hot water discharged from conventional plants (cogeneration) and that available from the lower temperaturegeothermal resources (75 - 130 °C); 2) the cascaded use of
hot water discharged from geothermal power stations for
direct heat applications; 3) the huge geothermal energy
potential available within drilling depths (3 - 10 km) in theearth’s crust via enhanced geothermal systems (EGS)
development; 4) the large energy resources in the form ofsuper-critical fluids inferred to exist deep (3 - 5 km)
2Mongillo, Bromley and Rybach.
beneath hydrothermal systems; 5) hot water produced fromoil and gas wells; 6) hot water present in deep sedimentarybasins and 7) off-shore (under-sea) hydrothermal resources
located along the submarine rifts and identified by thepresence of hydrothermal vents.

required to produce confident estimates of its possible
contribution.
4. THE INTERNATIONAL ENERGY AGENCY (IEA)
AND IMPLEMENTING AGREEMENTS
The International Energy Agency (IEA) is an autonomousintergovernmental organization based in Paris, France.
Formed in 1974, in response to the 1973-74 oil crisis, the
IEA now acts as an energy policy advisor to its 28 member
countries: Australia, Austria, Belgium, Canada, Czech
Republic, Denmark, Finland, France, Germany, Greece,
Hungary, Ireland, Italy, Japan, Korea, Luxembourg, The
Netherlands, New Zealand, Norway, Poland, Portugal,
Slovak Republic, Spain, Sweden, Switzerland, Turkey, theUnited Kingdom and the United States; with the aim ofhelping ensure the provision of reliable, affordable andclean energy to their citizens. The Commission of theEuropean Communities also participates in the work of the
IEA.

Of the above non-conventional resources, EGS is the firstthat has been identified as having an extremely large
theoretical potential. Recent estimates indicate that the
USA has over 200,000 EJth extractable heat via EGS
techniques (about 2,000 times its 2005 annual primaryenergy consumption), with approximately 100 GWe of costcompetitive generating capacity developable by 2050, given
reasonable R&D investment (MIT, 2006). Estimates of
EGS potential for the Rehai and Yangbajing geothermal
fields of China (Wan et al., 2005) and for regions acrossIndia (Chandrasekhar and Chandrasekharam, 2007) also
show capacities on the order of 100 GWe, with further
assessments of 35 GWe for Germany (Paschen et al. 2003),
12 GWe for 23% of Switzerland (Signorelli and Kohl,
2007) and 13 GWe for 3 project areas of South Australia(Goldstein, pers. comm., 2008), making a total of ≥ 360
GWe. A recent (2009) first-order estimate of global EGS
theoretical potential of ~ 2 TWe was obtained by assumingthat the USA EGS capacity of 100 GWe for the UScontinental area applied to the worldwide continental landmass. Comparison of this estimate with the ≥ 360 GWe
value suggests that the global estimate is low. However,Fridleifsson et al. (2008) have indicated that 70 GWe of
EGS could be available by 2050; and Rybach’s (2010)
recent discussion of geothermal potential and the challenges
facing large-scale EGS deployment argues for the lower
value. Hiriart et al. (2010) have recently examined thepossibility of power generation from geothermal(hydrothermal) vents associated with active oceanic ridges,
and with conservative assumptions, find a total potential
production of 160 GWe. Discussions at a joint GIA-GIA
Workshop held in May 2009 highlight the continued
uncertainties associated with the estimating geothermal
potentials (Mongillo, in prep.).

In addition to its initial role of coordinating measures intimes of oil supply emergencies, the IEA’s mandate has
broadened and now includes: energy security, economic
development and environmental protection- the major
components of balanced energy policy making. Significant
joint measures include developing alternative energy
sources, increasing efficiency of energy use and assistingwith the integration of energy and environmental policies.
IEA’s current work concentrates on market reform, energy
technology collaboration, climate change policies andoutreach to the wider global community, especially the big
energy consumers and producers: China, India, Russia andthe OPEC countries. The IEA pursues an extensive
programme of data compilation, energy research,
publications and public dissemination of the most current
energypolicyanalysisandgoodpractices
recommendations.
See the IEA website for further
information.
Only international technology cooperation can provide a
cost-effective way to help guarantee energy security andaddress climate change issues. The IEA encourages suchinternational energy technology collaboration in the areasof information centres and energy modelling, fossil fuels,
renewableenergytechnologies,
energyend-usetechnologies and fusion power through a network of 41
Implementing Agreements (IAs). The IAs provide amanagement framework and legal mechanism for guiding
the IEA’s collaborative program activities. IA Members
are of two categories: Contracting Parties (representing
countries), and Sponsors (industries and organizations); andtypically consist of research institutions, utilities, industries
and organizations.

Currently, geothermal development for electricity
generation and direct use is in a high-growth phaseworldwide (Figure 1), with future prospects looking very
positive. It is not clear how the global financial crisis willaffect geothermal in the near future, though USA President
Obama announced on 27 May 2009, the American
Reinvestment and Recovery Act to expand and accelerate
the development, deployment, and use of geothermalenergy throughout the United States, with a US$ 350 M
stimulation package. This should not be surprising, sincegeothermal is a major renewable global energy resource,with a multitude of valuable characteristics, including its:
extensive global distribution, environmentally friendly
character, independence of season, immunity from weather
effects, indigenous nature, contribution to development ofdiversified power, effectiveness for distributed application,
sustainable development capabilities and small foot-print.
Though geothermal usually operates as a baseload providerof electricity with availability and load factors typicallywell above 90%, it can also operate in a load-following
capacity, albeit at lesser efficiency.

IA activities, or tasks, are defined and organized in annexes,
which specify task objectives, schedules and funding
provisions (if any), and identify participants and define
their obligations.
An Executive Committee (ExCo),
consisting of one representative from each Member,manages the activities of the IA and is responsible fordisseminating results and reporting to the IEA. Each annex
is led by an Operating Agent, usually an institution.
Funding for IA annex activities can be of two types: tasksharing, wherein participants provide resources andpersonnel to conduct a portion of the annex work at theirown expense; or cost-sharing, whereby participants
contribute to a common fund that is used to pay for annex
operation. A combination of these funding mechanisms
may also be used.

Clearly, there is the potential for geothermal resources tomake a considerable contribution towards meeting theworld’s current and future energy needs well into the future,
while contributing to reduced future emissions and to themitigation of climate change. The global geothermal
potential is enormous; however, more detailed studies are3

In stalled C ap acity (M W e)

Mongillo, Bromley and Rybach

14,00013,00012,00011,00010,000
9,000
8,000
7,000
6,000
5,000
4,000
3,000
2,000
1,000
0
1970

1975

1980

1985

1990

1995

2000

2005

2010

2015

Year
Figure 1. Worldwide geothermal installed capacity 1975-2010 (red triangle is installedcapacity in 2007, yellow circle is Bertani (2007) estimate for 2010 and the blue circle
is Gawell and Greenberg (2007) estimate for 2010).

encouraged to attend. Country and Sponsor Members reporton the status of their geothermal activities; and prospective
new Members and invited guests describe their geothermal
pursuits and interests.
Separate Annex meetings are
frequently held in association with the ExCo meetings.
Members cover the travel expenses of their representatives
to attend the GIA meetings and associated workshops. etc..

5. THE IEA GEOTHERMAL IMPLEMENTINGAGREEMENT (GIA)
5.1 Overview
Founded in 1997, the GIA is now well into its 3rd 5-year
term of operation, which takes its activities to 2012. It
provides a flexible structure for comprehensive international
cooperation in geothermal R&D by linking national andindustry programmes for exploration, development andutilization of geothermal resources. The emphasis is onenhancing effectiveness through establishing direct
cooperative links among the geothermal experts in theparticipating countries, industries and organizations. The
general scope of the GIA’s activities consist of international
collaborative efforts to: compile and exchange improved
information on global geothermal energy R&D, develop
improved technologies for geothermal energy use, andimprove the understanding of the environmental benefits ofgeothermal energy utilization and ways to avoid or minimize
its environmental impacts. Collaboration through GIA
offers members the chance to participate in R&D projects,
and assist with the development of databases, models andhandbooks; as well as opportunities for informationexchange via meetings, workshops and networking; andprovides an international perspective on geothermal issues.

The GIA ExCo has a Secretariat, currently based in New
Zealand, which provides administrative and secretarial
services, assists with publications, maintains the GIA
website and provides other services as required for theorganization.
The operational expenses for the GIA
Secretariat, including the Secretary’s salary, and othercommon costs of the ExCo, are met from an ExCo common
fund. Contributions to support the common fund are madeby Members through a share apportionment system, witheach share currently valued at US$ 3,500/year.
GIA membership provides many valuable benefits,
including: increases R&D capabilities by combining theefforts of several nations and industry; helps avoid
duplication and unproductive research; develops skills andknowledge; improves R&D cost effectiveness by sharing
information, research costs and technical resources; provides
wider and easier access to key information, research results
and technological capabilities; provides impartial
information and analysis to help guide national policies andprogrammes; provides the opportunity to review current
issues, ongoing research and the need for future research;
investigates barriers to implementation; and contributes tothe development of energy policies.

As of May 2009, there were 19 Members in the IEA-GIA,
including: 12 countries (Australia, France, Germany,
Iceland, Italy, Japan, Mexico, New Zealand, Republic ofKorea, Spain, Switzerland, United States), the EC, 4industries (Geodynamics Limited, Green Rock Energy
Limited, ORME Jeotermal, Inc., Ormat Technologies, Inc.)and 2 national organizations (the Canadian Geothermal
Energy Association [CanGEA] and the Geothermal Groupof the Spanish Renewable Energy Association [GG-APPA]).

5.2 Initiating GIA Sustainable Development Efforts
The IEA-GIA identified sustainable utilization as animportant topic for consideration at the time of its formation;and in 2003, drafted Annex V- Sustainability of Geothermal
Energy Utilization. The efforts of this proposed Annex were
aimed at investigating alternative scenarios for energy
production from representative geothermal resources withThe GIA ExCo, which consists of one voting representativefrom each of the above 19 Members, supervises the overall
operation of the organization. It meets twice each year toreport on and discuss the organization’s activities, especiallythose pursued in the annexes; and Members are stongly4Mongillo, Bromley and Rybach.
the goals of (1) defining methods and requirements forsustaining production from these resources, and (2)estimating the long-term economic sustainability of suchproduction not only for representative resources but for theworldwide geothermal resource as a whole. To date, thisAnnex has remained inactive, awaiting two members tochampion it.

•

To collect, improve, develop and disseminate
geothermal RD&D policy information for IEA Member
and non-Member Countries•

To identify geothermal energy RD&D issues andopportunities, and improve/develop geothermal energy
technologies and methods to deal with them

In 2006, the ExCo decided to support an initial investigation
into developing a GIA sustainability policy with the possiblyof initiating the GIA’s geothermal sustainability efforts, anda review paper that examined geothermal’s renewablecharacteristics and its sustainable development withassociated identified research needs was prepared (Rybach
and Mongillo, 2006). This paper stimulated much useful
discussion, and along with a paper that examined geothermal
utilization strategies to promote beneficial environmental
effects and optimize sustainability (Bromley et al., 2006),
set the scene for the creation and official start-up of the
GIA’s sustainability studies in late 2006, in Annex I Task ESustainable Utilization Strategies.

•

To increase membership in the GIA•

To encourage collaboration with other internationalorganizations and appropriate IEA implementing
agreements•

To broaden and increase the dissemination of
information on geothermal energy and the GIA’s
activities and outputs to decision makers, financiers,
researchers and the general public

Though the above mission and objectives were developed inlate 2006 as part of the GIA’s 3rd Term Strategic Plan, they
still remain sound and continue to provide excellent
guidance for the GIA’s activities, even considering the moreominous IEA climate-based outlook (IEA, 2008b) and thefinancial crisis currently challenging the world.

The aim of Task E was to collate case histories of models ofgeothermal developments to see what strategies haveworked; undertake modelling of long term reservoir
behaviour to select optimum future strategies given different
recharge and resource size scenarios; compare
environmental gains with economic gains from different
sustainable development scenarios; compare different
conceptual and hypothetical reservoir model predictions, andinvestigate (with agreed scenarios) long term reservoir
behaviour, recharge factors, recovery times, and optimised
cyclic or staged operation strategies. Task E continues to bevery active and productive (see below).

6. CURRENT GIA ACTIVITIESTo help meet the above objectives and realize the GIA’s
mission, GIA participants take part in one or more of thecurrent four major research areas, or Annexes. In addition,
ExCo Members and the Secretary also contribute (seesection 6.2 below).
6.1 The Annexes
The GIA’s current major efforts are managed in thefollowing four Annexes, with specific studies conducted inseveral Tasks within each Annex (See Table 1 for Annex
information).

In the meantime, the ExCo had unanimously agreed to apply
to the IEA to continue its operations for a 3rd Term (20072012). It identified the importance of promoting sustainable
geothermal development for realizing geothermal’s huge
global potential as a clean, economic and secure energy
resource that could contribute to the mitigation of climatechange; and so adopted this goal as the core of its proposed
3rd Term mission.

Annex I: Environmental Impacts of Geothermal Energy
Development- to determine the environmental effects ofgeothermal development and develop and implement
methods to avoid or minimize their impacts. Five tasks
include: to examine the impacts on natural features; to study
the problems associated with discharge and reinjection ofgeothermal fluids; to examine methods of impact mitigationand produce environmental guidelines; to investigate seismic
risk from EGS fluid injection; and to develop sustainableutilization strategies (for further details, see Axelsson et al.
(2010), Bromley (2010)).

5.2 3rd Term Mission and Objectives
To continue and expand global geothermal development, it
is essential to improve and develop new technologies and toincrease awareness of geothermal energy and the benefits of
its sustainable utilization. The IEA-GIA sees itself as anorganization that can take the lead in these efforts, andembraced them its 3rd Term Mission:

Annex III: Enhanced Geothermal Systems (EGS)- toinvestigate new and improved technologies that can be used
to artificially stimulate a geothermal resource to allow
commercial heat extraction. Five tasks include: to develop
EGS economic models; to review/modify application of
conventional or new geothermal technologies; to collectinformation necessary for designing a commercial EGS
plant; to compile effective tools for reservoir evaluation thatcan be applied to new EGS sites; and to conduct EGS R&D
with emphasis on reservoir management and enhancement
technologies (for further details, see Baria and Wyborn.
(2010)).

To promote the sustainable utilization of geothermalenergy throughout the world by improving existing anddeveloping new technologies to render exploitable the vast
and widespread global geothermal resources, byfacilitating the transfer of know-how, by providing highquality information and by widely communicating
geothermalenergy’s
strategic,
economic
andenvironmental benefits.
To accomplish this mission, the following six strategic
objectives were designed:•

To actively promote effective cooperation in
geothermal RD&D through collaborative work
programmes, workshops and seminars

Annex VII: Advanced Geothermal Drilling Techniques- to
pursue advanced geothermal drilling research andinvestigate all aspects of well construction with the aim of
reducing costs. Three tasks include: the compilation ofgeothermal well drilling cost and performance information;
the production of a geothermal drilling “best practices”
5

Mongillo, Bromley and Rybach
handbook; and the exchange of information on drilling
technology development and new applications (for further
details, see Bauer et al. (2010)).

equipment; to develop engineering standards; and to develop
methods for presenting geothermal data on the internet using
Google Earth (for further details, see Gunnlaugsson et al.
(2010), Muraoka et al. (2010), Rybach (2010), Song(2010)).

Annex VIII: Direct Use of Geothermal Energy- to address
all aspects of direct use technology with emphasis on
improving implementation, reducing costs and enhancing
use. Six tasks include: to define and characterize geothermal
resources for direct use applications; to collect, analyze anddisseminate cost and performance data and validate
improvements; to initiate research to remove barriers,
enhance economics and promote implementation; toidentify, test and characterize performance of innovative

GIA Members must participate in at least one of the Annex
Tasks, though all current Members are participating in 2 ormore Tasks. Funding for GIA Annex work has been of thetask-sharing mode since the initiation of the GIA, and is
expected to remain so for the foreseeable future.

Table 1. Annex Title, Operating Agent and Status of GIA Annexes at May 2009.
Annex
Number

Title
Operating Agent (OA)
Task Leader (TL); Affiliation; Contact E-mailParticipants

StatusI

Environmental Impacts of Geothermal Development
OA: GNS Science (GNS), New Zealand
TL: Chris Bromley; GNS, New Zealand; c.bromley@gns.cri.nz
Participants: Australia, EC, France, Iceland, Italy, Japan, Mexico, New Zealand,
Switzerland, USA

Active since 1997,
Continuing through 2009

II

Shallow Geothermal Resources

ClosedIII

Enhanced Geothermal Systems
OA: Geodynamics Limited, Australia
TL: Roy Baria, MIL-TECH UK (for Geodynamics); roybaria@onetel.com
Participants: Australia, Canadian Geothermal Energy Association, EC, France,
Geodynamics, Geothermal Group-Spanish Renewable Energy Association,
Germany, Green Rock Energy, Italy, Japan, ORMAT, Spain, Switzerland, USA

Active since 1997,
Continuing through 2009

IV

Deep Geothermal Resources

ClosedSeptember 2006

V

Sustainability of Geothermal Energy Utilization

Draft

VI

Geothermal Power Generation Cycles

Draft

VII

Advanced Geothermal Drilling Techniques
OA: Sandia National Laboratories, United States
TL: Steven Bauer; Sandia National Laboratories, USA; sjbauer@sandia.gov
Participants: Australia, Canadian Geothermal Energy Association, EC, Iceland,
Mexico, New Zealand, USA

Active since 2001,
Continuing through 2009

VIII

Direct Use of Geothermal Energy
OA: The Federation of Icelandic Energy and Waterworks, Iceland
TL: Einar Gunnlaugsson; The Federation of Icelandic Energy and Waterworks,
Iceland; einar.gunnlaugsson@or.is
Participants: Canadian Geothermal Energy Association, France, GeothermalGroup-Spanish Renewable Energy Association, Iceland, Japan, New Zealand,
ORME Jeotermal, Republic of Korea, Spain, Switzerland, USA

Active since 2003,
Continuing through 2011

IX

Geothermal Market Acceleration

ClosedAnnex II- Shallow Geothermal Resources and IV- Deep Geothermal Resources, were closed after successful completion of
their major tasks; and Annex IX was closed before it was initiated as the result of the IEA starting a special Implementing
Agreement: Renewable Energy Technology Development.

6

Mongillo, Bromley and Rybach
others), and explain and discuss it with non-geothermal
participants, policy and decision makers, and the public. At
the exhibition booth, many posters were displayed andcomputer presentations were projected continuously;
hundreds of geothermal and GIA documents were
distributed; and the GIA’s work was discussed with amultitude of visitors, including scientists, business people
and students.

6.2 The ExCo and Secretariat
In addition to supervising the overall operation of the GIA
programme, the ExCo supports the IA’s efforts through its
Member’s, and the Secretary’s, general promotion andinformation dissemination on geothermal energy and the
GIA through their participation at international renewableenergy and geothermal conferences and workshops, withspecial effort made to support those sponsored by the IEA.
Other activities include: publication, in international
journals, of papers describing the GIA’s activities;
production of comprehensive GIA annual reports;
maintenance of the public GIA website; and sponsorship ofconference exhibition booths, where documents, posters andother material can be distributed.

The GIA has increased its participation in IEA workshops,
meetings and seminars, through direct participation and theprovision of GIA material for distribution. The GIA has
participated at the China (Mongillo and Rybach, 2007) andRussia (Mongillo, 2008) IEA Networks of Expertise in
Energy Technology (NEET) workshops designed toencourage these countries to increase their use of moreenvironmental-friendly renewable energy. Both China andRussia have geothermal power and direct use developments
and were interested in learning about the GIA’s activities
and how membership could help their geothermal
programmes. The GIA also provided posters and several
documents for the IEA Ministerial Fair held in Paris, France(2007), which many high-level government officials
attended.

7. RECENT GIA ACHIEVEMENTS IN SUPPORT OF
SUSTAINABLE DEVELOPMENTThe GIA’s sustainability activities have grown since the startof its 3rd Term in April 2007. A few examples which
demonstrate the range of work and major accomplishments
are presented here.
7.1 3rd Term Extension
The GIA identified sustainable geothermal development as
one of the industry’s most significant current, and future,
issues, and so designed its 3rd Term mission and strategic
objectives to deal with it. Following a rigorous review of
the GIA’s strategy, the IEA concurred and unanimously
extended the GIA’s activities for a 3rd 5-year Term, toMarch 2012.

Information and data are regularly provided for IEA reports,
thus raising the profile of the GIA and geothermal energy
within the IEA, as well as on a global scale, and among theother renewable energy technologies. An example is the
IEA bi-annual Energy Technologies at the Cutting Edge
reports, which included highlights of the GIA’s EGS
activities in 2007, and will cover the GIA’s sustainability
efforts in 2009. The GIA has also contributed articles to
IEA OPEN Bulletin, an electronic newsletter with over
12,000 subscribers, most recently dealing with induced
seismicity associated with EGS (Bromley and Mongillo,2008).

7.2 Membership Growth
The ExCo recognizes the importance of increasing
membership in order to enhance its expertise, extend its
efforts and increase its influence in support of sustainable
geothermal utilization worldwide; and so has emphasized its
membership growth effort. In 2006, the GIA also broadened
its membership base to include both industry and industry
organizations, thus providing direct industry contact,
perspective and input; thereby helping raise GIA’s
awareness of their concerns and needs. In the past 3 years,
membership has nearly doubled to a total of 19 Members,
with 12 Country Members, the EC and 6 Sponsor Members.
At present, there is also interest from five prospective
members: Norway, the European Geothermal Energy
Council (Belgium), China, Russia, and Ireland.

The GIA Annual Reports, and associated stand-alone
Executive Summaries (2005, 2006 and 2007), have become
the GIA’s premier forms of information dissemination.
They provide up-to-date information about the organization,member’s geothermal activities and Annex efforts; and sincethe 2005 issue, CD-Roms including all GIA Annual Reports(1997-2007) and Executive Summaries have been produced
for distribution at international conferences and uponrequest.
The GIA’s comprehensive public website went on-line inlate-2004 (www.iea-gia.org), and is being continuously
developed and updated. It provides an important and easily
accessible means for distributing and commenting on GIA
documents and other international publications, as wellmaking available up-to-date information about the GIA andgeothermal energy to GIA Members and the public

7.3 Significant Information Dissemination
The GIA ExCo and Annexes have been particularly active
and successful in their information dissemination
endeavours since the start of the 3rd Term, with participationin several major international conferences, meetings andworkshops, including: the European Geothermal Congress(2007), Unterhaching, Germany; and the 2008 New ZealandGeothermal Workshop (NZGW), Taupo, New Zealand,
which was held in association with the 50th Anniversary of
the commissioning of the Wairakei Geothermal Power
Station. These conferences provided valuable opportunities
for extensive discussion and information exchange withother geothermal professionals.

The GIA has also expanded its activities bysponsoring/hosting
severalinternational
technical
workshops since 2005. In November 2008, Annex I
sponsored an International Geothermal Sustainability
Modelling Workshop in Taupo, New Zealand, in association
with the 2008 NZGW and the 50th Anniversary of the
Wairakei Power Station. There were over 40 participants;
with 20 presentations examining geothermal development
strategies and numerical modelling, which have been madeavailable to the international community via the GIA
website. Discussion and follow-up networking has lead tothe development of a Geothermics Special Issue on
Sustainable Geothermal Utilization, planned for publicationin early 2010. It is to include case histories and modelling

The GIA also had a major presence at the large Renewable
Energy 2008 Conference, Busan, Korea, with thepresentation of several geothermal papers about the IEAGIA’s efforts and geothermal utilization; and sponsorship ofan exhibition booth that attracted good attention. The RE
2008 was especially valuable because it provided theopportunity for the GIA to raise awareness of geothermal as
an important renewable energy source (amongst all the7Mongillo, Bromley and Rybach
results illustrating various sustainable utilization methods
for most of the major developed geothermal fields with long
periods of power and direct use production. More recently,
in May 2009, a joint GIA-IGA (International Geothermal
Association) Workshop on Geothermal Energy- Its Global
Development Potential & Contribution to Mitigation of
Climate Change was held in Madrid, Spain. Over 60
participants from about 20 countries discussed these issues,
and a proceedings consisting of a summary of workshop
discussions and all presentations is being prepared.

8. FUTURE DIRECTIONS, OPPORTUNITIES AND
PLANS
Geothermal power and direct use development are currently
in a period of major growth in many countries. However, inspite of geothermal’s huge potential and valuablecharacteristics, this rate of development (< 2 GWe/yr,
Bertani (2009)) is far outstripped by those of solar PV (6GWe/yr) and wind (25 GWe/yr) (Renewables, 2009).
Clearly, geothermal still faces serious obstacles, including
technical, financial, political and perceived barriers thatmust be overcome if geothermal is to realize its huge
potential and make the more rapid contribution it is capableof. The GIA believes its current strategy is sound andprovides good direction to meet these challenges, however,it also sees opportunities to further its success and influence.

In 2009, the GIA ExCo has, for the first time, been able to
make funds available for specific GIA and Annex projects,
such as the completion of specific studies and production of
special reports. The first proposal funded is to support the
publication of the Geothermics Special Issue on Sustainable
Geothermal Utilization described above.

Information dissemination, exchange and communication
will remain major activities for the GIA, and newopportunities have been identified for further developing
these efforts, with the aim of expanding the communicationof the benefits of geothermal energy and the GIA’s activities
and results to as wide an audience as possible. The GIA willcontinue to participate at major international renewableenergy and geothermal meetings, conferences andworkshops. Possibilities are being explored for holding
more regular international workshops and seminars inassociation with ExCo meetings, in prospective Member
countries and with other international organizations, such as
the IGA. The GIA will be building on its already strong ties
with its IEA parent, most immediately by producing a
geothermal brochure (IEA Geothermal Technology Brief)
with the IEA, which will provide recognition and widecirculation among the policy makers of the 26 IEA Member
countries and EC, and provide a substantial document for
distribution
through
GIA
channels,international
conferences, etc.
The Geothermics Special IssueSustainable Geothermal Utilization, planned for release inearly 2010, will be an important publication for informing
the international community about current sustainable
geothermal power and direct use operations, the various
development options being used, and the IEA-GIA’s efforts
to promoting sustainable development. The GIA will also
be sponsoring an exhibition booth at the WGC 2010, at
which several posters describing the GIA, Annex studies andMember Country and Sponsor geothermal activities will be
displayed, and many IEA and GIA documents madeavailable.

7.4 Recent Annex Efforts and Achievements
A few examples of the more important Annex-related efforts
and achievements are described here.
Near the start of the 3rd Term, Annex III activities weresignificantly revised in recognition of the first EGS power
stations approaching completion. New investigations were
included to develop economic guidelines for EGS reservoir
economic models and design recommended procedures tocreate, test and evaluate EGS parameters. These efforts willcontribute to the development of sustainable EGS operation
procedures.
Annex I’s induced seismicity efforts- 3 international
workshops held between 2005 and 2006, and othercontinuing investigations, culminated in the development of
a Protocol for Induced Seismicity Associated with EGS(Majer et al., 2008) which could serve as a guide fordevelopers to use to address induced seismicity issues. In
addition, a paper was produced which reviewed induced
seismicity, presented up-to-date information, identified gaps
in knowledge, and concluded that EGS-induced seismicity
need not be a threat to EGS development (Majer et al.,2007). Annex I’s important sustainability accomplishments
were described above.
Annex VII continues to make progress on the developmentof a database of comparative well costs, downhole logging
tool improvements, and production of a best-practices
drilling handbook. The particular importance of reducing
well drilling and completion costs is well recognized, andsignificant success here will provide a major boost to
geothermal sustainable development.

The GIA has plans to produce a proceedings from the joint
international GIA-IGA Geothermal Potential andGeothermal’s Contribution to the Mitigation of Climate
Change Workshop held in May 2009, consisting of a précisof the 2-day discussions plus copies of all presentations.
The proceedings will be made available on CD-Rom and on
the GIA website.

A significant database of temperature and chemistry data forgeothermal features from several countries has beenassembled (and continues to grow) by Annex VIII, and will
make a valuable contribution to the production of theplanned Atlas of World Hydrothermal Systems and provide
information useful for increasing direct use applications.
Initial published results (Muraoka et al., 2008) demonstrate
the great value of having a comprehensive database fromwhich data can be compared and geographically plotted; andindicate that surface feature discharge temperature mapping
clearly depicts up-flow zones of hydrothermal systems andcan be a useful tool for identifying prospective geothermal
fields. Improved public accessibility to direct use data via
Google Earth has been demonstrated, with full operation
expected in the near future.

The GIA will continue to develop both its annual report asits premier GIA information product, and its public website
as its most widely and easily accessible avenue forcommunication and information distribution. Plans for
upgrading the GIA website are currently being considered,with outcomes to include making site updating/editing
easier, downloading of documents/information from the site
faster, assuring the GIA site appears more prominently oninternet search lists, and providing more information aboutsite visitors.
The GIA is always prepared to consider new collaborative
activities and new proposals are encouraged where demandand needs exist.
Interest is growing in sustainable8Mongillo, Bromley and Rybach.
geothermal development and several research needs havebeen identified, and if/when sufficient interest isdemonstrated, the GIA is prepared to expand its efforts byinitiating Annex V- Sustainability of Geothermal Energy
Utilization. Similarly, the GIA has experienced a significant
increase in requests for geothermal data and information
over the past few years, and is now considering the creationof an Information Exchange and Dissemination Annex.

Technology, Proceedings World Geothermal Congress
2010, Bali, Indonesia (2010).
Bertani, R.: Long-term projections of geothermal-electric
development in the world. Proceedings, GeoTHERM
Congress, Offenburg/Germany, 5-6 March 2009.
Bertani, R.: World Geothermal Generation in 2007.
Proceedings European Geothermal Congress 2007, 30
May- 1 June 2007, Unterhaching, Germany (2007),
11p.

The GIA recognizes the need for continued growth,
especially seeking those countries with significant
geothermal resources and/or development whose
membership would benefit both the GIA and them,including: Indonesia, the Philippines, and countries in East
Africa and Central and South America. Potential members
are encouraged to attend GIA ExCo meetings, workshops
and Annex meetings to learn more about the GIA and thebenefits of membership. At present, there is membershipinterest from Norway, the European Geothermal Energy
Council (EGEC), Ireland, Russia and China; and continued
growth is expected.

Bromley, C.J.: Promoting Beneficial Environmental Effects
and Improving Long-Term Utilization Strategies
Through IEA-GIA Collaboration, Proceedings World
Geothermal Congress 2010, Bali, Indonesia (2010).
Bromley, C.J. and Mongillo, M.A.: Geothermal energy fromfractured reservoirs: dealing with induced seismicity,
IEA OPEN Energy Technology Bulletin, 48 (2008), 7p.
Bromley, C.J., Mongillo, M.A.., Rybach, L., Jelacic, A. andSong, Y.: Geothermal Energy- IEA-GIA’s Efforts
Towards Accelerating Development of this Global,
Under-Utilized Renewable Resource, Proceedings,
Renewable Energy Congress, Busan, Korea (2008).

9. CONCLUSIONS
The worldwide demand for energy is expected to continue
growing over the next several decades, irrespective of thecurrent global financial crisis. Unless energy savings andrenewable energy options are implemented, energy security
problems and significant climate change effects are likely.
To meet these challenges will require massive input fromrenewable energies, including that from the vast andubiquitous geothermal resources.

Chandrasekhar, V. and Chandrasekharam, D.: Enhanced
Geothermal Resources, Indian Scenario, Transactions,
Geothermal Resources Council, 31 (2007), 4p.
Gawell, K. and Greenberg, G.: 2007 Interim Report –Update on World Geothermal Development, 1 May
2007 (2007), (available on GEA website:
http://www.geo-energy.org/publications/reports.asp).

However, to realize geothermal’s huge potential
contribution, it is necessary to improve existing and develop
new technologies; and to promote the benefits of geothermalenergy, its sustainable utilization and the contribution it canmake toward climate change mitigation. Success will
require considerable international effort.

Gunnlaugsson, E.: IEA GIA Annex VIII- Direct Use of
Geothermal Energy, Proceedings World Geothermal
Congress 2010, Bali, Indonesia (2010).
Hiriart, G., Prol-Ledesma, R.M., Alcocer, S. and Espíndola,
S.: Submarine Geothermics; Hydothermal Vents andElectricity Generation, Proceedings World Geothermal
Congress 2010, Bali, Indonesia (2010).

The IEA-GIA, now well into its 3rd 5-year Term, and with ademonstrated record of success, is well placed to lead thisessential international effort, and is confident that it can doso well into the future. The participants in the IEA-GIA
extend an invitation to those national organizations,
universities, industries and other groups who can contribute,to join us in our endeavours.

IEA.: World Energy Outlook 2008- Executive Summary,OECD/IEA, Paris (2008a), (available on IEA website:
http://www.iea.org/Textbase/npsum/WEO2008SUM.pdf).
IEA.: World Energy Outlook 2008, OECD/IEA, Paris(2008b), 569 p.

For more information about the IEA-GIA, contact the IEAGIA Secretary and/or visit the GIA website.

IEA.: IEA Key World Energy Statistics 2008, OECD/IEA,
Paris, France (2008c).

ACKNOWLEDGEMENTS
The authors gratefully acknowledge the constant support of
the IEA-GIA participants, which has made this paper
possible.

IEA.: IEA World Energy Outlook 2007: Fact Sheet- Global
Energy Demand, 2 p. (document available at:
http://www.iea.org//textbase/papers/2007/fs_global.pdf).
IEA website: www.iea.org.
IEA-GIA Secretary: mongillom@reap.org.nz.

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