Energy Research
Knowledge Centre
Overcoming
Research
Challenges
for Geothermal
Energy
E n e r g y
R e s e a r c h
K n o w l e d g e
This publication was produced by the Energy Research Knowledge
Centre (ERKC), funded by the European Commission to support its
Strategic Energy Technologies Information System (SETIS). It represents
the consortium’s views on the subject matter. These views have not
been adopted or approved by the European Commission and should
not be taken as a statement of the views of the European Commission.
The manuscript was produced by Massimo Angelone and Stefano
Sylos Labini from the Italian National Agency for New Technologies,
Energy and Sustainable Economic Development (ENEA).
The purpose of this brochure is to summarise comments and recommendations reported in previous documents from national and
international organisations working on renewable energy or involved
in geothermal activities.
While the information presented in this brochure is correct to the best
of our knowledge, neither the consortium nor the European Commission
can be held responsible for any inaccuracy, or accept responsibility for
any use made thereof.
Additional information on energy research programmes and related
projects, as well as on other technical and policy publications is
available on the Energy Research Knowledge Centre (ERKC) portal at:
setis.ec.europa.eu/energy-research
Manuscript completed in September 2014
© European Union
Reproduction is authorised provided the source is acknowledged.
Cover: © GOPAcom
Photo credits: Istockphoto, ECN, Shutterstock
Printed in Belgium
C e n t r e
Overcoming Research Challenges for Geothermal Energy
Contents
Key messages
2
Current status of geothermal energy
3
Challenges and potential of geothermal
5
Figuring out the future for geothermal
- Geothermal energy in EU Member States
- Geothermal strategies in non-EU countries
6
11
14
Research and opportunities
- Exploring and drilling technologies
- Electricity production
- Heating and cooling
- Desalination
- Environmental impact mitigation and public acceptance
17
17
17
20
21
22
Looking to the future
23
Policy implications and recommendations
26
References
28
Selected websites on geothermal energy
31
List of Acronyms
32
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Key messages
• Emerging technologies for electricity production are at early-commercial
stage and technological innovation for cost reduction is required as well
as deployment of large-scale Enhanced Geothermal System plants
• RD&D financial support and a new regulation framework
are necessary for electricity exploitation
• Demand pull in the exploitation of heating and cooling is crucial
• Pilot projects for volcanic islands are advisable in order
to achieve a higher energy independence
• Need for environmental and socio-economic assessment and
inf
information
to population involved in deep geothermal exploitation
Natural
geothermal
energy plant
in Pisa, Italy.
© iStockphoto
Overcoming Research Challenges for Geothermal Energy
Current status
of geothermal energy
This Geothermal Energy Policy Brochure
summarises the current status of developments in geothermal energy. Emphasis is
placed on the results of geothermal energy
research programmes and their implications
on future policy decisions and technological
challenges.
• There is a mismatch between research,
development and demonstration (RD&D)
and industrial applications: the current
large research programmes are not connected to immediate industrial applications, but look towards future developments, while current applications, such as
heating and cooling (HC), are not associated with large RD&D projects because
they are related to consolidated technologies that require incremental innovations.
• In 2013, shallow geothermal was the largest sector in terms of installed capacity
with 63 % of total capacity, followed by
direct use with 30 % and electricity with
7 %. In 2012, about 100 000 geothermal heat pumps (GHP) were installed in
the European market and total number
of GHP in operation within the European
Union (EU) is about 1 million units. The
number of operational geothermal power
plants is 68, providing an installed capacity of 935 MWe (megawatt electric) and
producing 5 820 GWe (gigawatt electric).
The direct and indirect jobs provided number about 11 000 units in the geothermal
electric sector and about 100 000 units in
the GHP sector.
• These data show that the exploitation of
deep geothermal energy for electricity
production, in particular Enhanced Geothermal Systems (EGS), has a low impact
on the economy, notwithstanding the fact
that major research projects are focusing
on this field. On the contrary, geothermal
applications that are economically important, mostly heating and cooling, are not
linked to major research projects, but
mainly depend on the new construction
market trend and on investments in renovating old buildings.
• For these reasons, a relevant increase in
RD&D investment for exploiting electricity
production requires effective policies to
stimulate innovation and experimentation
by launching new demonstration projects
in order to move to large-scale EGS plants
(the so-called “technology push” strategy).
This approach implies a qualitative leap
by governments and banking systems as
well as in the involvement of large corporations which should play an active role
in the network of universities and public
research centres.
• In the HC sector it is important to set up
financial incentives and legislative rules
in the new construction market to stimulate the use of geothermal technologies (“demand pull” policies) and thereby
growth in production and innovation processes in the heat pump sector. Furthermore, it is essential to reduce permissions
and authorisations in order to liberalise
installations of heat pumps.
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• Last but not least, gas emissions and
micro-seismicity are factors that reduce
public confidence in EGS development.
For this reason, it is still worthwhile fully
assessing the social and environmental
impact of the activities by developing new
tools for analysis and involving the population in the geothermal projects in order to
achieve wide public acceptance.
Geothermal
power plant
production line.
© iStockphoto
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Overcoming Research Challenges for Geothermal Energy
Challenges and
potential of geothermal
The importance of geothermal energy originates from the availability and continuity of
the source for heat exploitation, and the fact
that it is clean energy which produces low
harmful emissions and ensures cost stability for end-users. Furthermore, geothermal
energy presents no geopolitical risk and can
be used with the current industrial technology for HC, which has a significant impact on
EU employment and gross domestic product
(GDP). HC technologies are competitive, are
characterised by a good level of diffusion,
and are more dynamic than those in the
electricity sector.
of a geothermal project, while technologies
for offshore and magmatic exploitation are
still at the experimental stage. In addition,
regulations and administrative procedures
represent obstacles that do not encourage
the application and diffusion of this renewable energy.
Conversely, geothermal energy has some
limitations and barriers to overcome: high
temperatures are concentrated in specific
areas, geothermal energy has a lower capacity factor compared to fossil fuel and nuclear
energy, and there are frequent mismatches
between optimal energy site locations and
district requirements. Furthermore, electricity grids need to be upgraded. The negative
impacts are mainly related to hot water and
gases released into the environment and
to the occurrence of induced earthquakes
triggered by rock fracturing, as has been
observed at some experimental EGS plants.
• improvements needed for resource assessment and forecasting;
• improvements in modelling and drilling
technologies;
• fracturing techniques, water supply, and
seismic 3D reservoir assessment;
• transmission and system integration;
• environmental impact mitigation.
Technological barriers lie mainly in high
exploration and high investment costs for
electricity production, long-term investment
return, and the risk of failure during the
exploration and drilling/stimulation phase
This brochure aims to provide suggestions for
promoting awareness of geothermal technologies and their real potential. It highlights the
current status of the different applications for
geothermal energy development. The main
issues to be tackled are:
The Geothermal Energy PB also focuses on
the current status of energy research regarding different technologies, based on the main
European and international programmes, in
order to show where the research should be
focused to facilitate the spread of geothermal technologies.
Finally, suggestions are made for the development and diffusion of innovative geothermal applications in different sectors (residential, industrial, water desalination).
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Figuring out the
future for geothermal
Geothermal energy is a dynamic and flexible
source of renewable energy which is recognised as making a significant contribution to
Europe’s energy mix since it could provide
continuous heat production almost everywhere.
First, the European strategy for geothermal
energy development is related to the Directive on the promotion of the use of energy
from renewable sources, adopted on 23 April
2009 (Directive 2009/28/EC). According to
Article 4 of this Directive, Member States
must adopt a National Renewable Energy
Action Plan (NREAP) setting out national targets for the share of energy from renewable
resources in electricity, heating and cooling,
and transport, and the measures to be taken
to achieve those targets. The following tables
show the NREAP energy production targets
from geothermal resources for each Member
State for the years 2015 and 2020.
Most electrical applications should double their output in 2020 (10.9 TWh with
1 613 MW of installed capacity). Among
the EU countries, France, Germany, Italy
and Portugal should expand their existing
installed capacity, while Greece, Hungary
and Spain should develop their own sectors,
in particular by operating binary cycle plants.
(EurObserv’ER, 2013).
The energy output from geothermal installations should increase significantly by 2020
to reach 2551 ktoe (thousand tonnes of oil
equivalent), with an interim target of 1296
ktoe by 2015 (ECN, 2011).
In the Working Document SEC(2011) 131
‘Review of European and national financing of
renewable energy in accordance with Article
23(7) of Directive 2009/28/EC’, the European
Commission pointed out that the feed-in tariff
is the main instrument in the EU for supporting
geothermal electricity. The costs of capital for
renewable energy system (RES) investments
observed in countries with established tariff
systems have proven to be significantly lower
than in countries using other instruments that
involve higher risks for future return on investments (ECOFYS et al., 2010).
Austria, Czech Republic, France, Germany,
Greece, Hungary, Portugal (Azores only),
Slovakia, Slovenia, Spain and Switzerland
have dedicated feed-in tariffs for geothermal energy. The most attractive schemes
are found in Switzerland (max. ct€ 33/kWh),
Germany (ct€ 25/kWh for all projects and an
additional ct€5 for EGS) and France (ct€ 20/
kWh with an energy efficiency bonus of up
to ct€ 8/kWh).
Estonia, Italy, the Netherlands and Slovenia
promote geothermal electricity generation by
means of feed-in premiums (a bonus paid
on top of the electricity market price) as an
alternative to feed-in tariffs. Currently, Belgium (Flanders), Romania and the UK have
a quota system in place based on green certificates (EGEC, 2013).
Overcoming Research Challenges for Geothermal Energy
Table 1: Projected geothermal electricity generation for the period 2015-2020, GWh
Belgium
Czech Republic
Germany
Greece
Spain
France
Italy
Hungary
Austria
Portugal
Slovakia
TOTAL
2015
0
18
377
123
0
314
6 191
29
2
260
28
7342
2020
29
18
1654
736
300
475
6 750
410
2
488
30
10 892
Source: NREAPs, ECN (2011)
Table 2: Projected total geothermal heat energy for the period 2015-2020, ktoe
Belgium
Bulgaria
Czech Republic
Denmark
Germany
Greece
Spain
France
Italy
Lithuania
Hungary
Netherlands
Austria
Poland
Portugal
Slovenia
Slovakia
TOTAL
Source: NREAPs, ECN (2011)
2015
4
3
15
0
234
23
5
310
260
4
147
130
27
57
18
19
40
1 296
2020
6
9
15
0
686
51
10
500
300
5
357
259
40
178
25
20
90
2 551
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In the HC sector, given the existence of consolidated technologies, it seems more effective to use a “demand pull” mechanism that
works by incentives granted to geothermal
technology applications in order to stimulate
the growth of production and innovation processes. Operational aid similar to a feed-in
tariff system is now beginning to be explored
in some Member States, partly because of
the inclusion of the sector in the European
regulatory framework.
The Communications ‘Energy Roadmap 2050’
(COM(2011) 885) and ‘Renewable energy: A
major player in the European energy market’
(COM(2012) 271) point out how crucial it is
to invest in new renewable technologies and
to improve existing ones through RD&D.
Production
line in thermal
power plant.
© iStockphoto
K n o w l e d g e
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The Implementing Agreement for the Cooperative Programme on Geothermal Energy
Research and Technology provides a framework for international co-operation on RD&D.
Activities include information sharing; developing best practice in the use of technologies
and techniques; exploration, development
and utilisation of geothermal; and producing
and disseminating authoritative analysis and
databases. There are currently 15 contracting
parties, including Iceland and Mexico, as well
as five sponsors.
Strategic research priorities in terms of
scientific research and development in
the geothermal sector were also identified
in two noteworthy documents: ‘Strategic
Research Priorities for Geothermal Technol-
Overcoming Research Challenges for Geothermal Energy
ogy’ (European Technology Platform on
Renewable Heating and Cooling – TP RHC
2012) and ‘Strategic Research Priorities for
Geothermal Electricity’ (European Technology Platform on Geothermal electricity - TP
Geoelec 2012). The aim of these Platforms
is devoted to reducing Europe’s dependency
on imported fossil fuels, stabilising energy
prices, and achieving climate change mitigation goals.
for refurbishing existing buildings, but also
for zero and plus energy buildings and to
develop geothermal District Heating (DH)
systems in dense urban areas at low temperature with emphasis in the deployment of
Enhanced Geothermal Systems. Finally, the
third goal is to contribute to the decarbonisation of the industry by providing competitive solutions for heating & cooling.
RD&D support from Member States must be
coordinated at European and national level.
Initiatives like Geothermal ERA NET, a consortium of funding agencies working together
to coordinate geothermal RD&D support programmes, and supported by the EU’s Seventh
Framework Programme (FP7), should enable
this coordination to be set up.
The Geothermal Technology Roadmap of the
European Technology Platform on Renewable Heating and Cooling (March 2014)
highlights the technological challenges for
an accelerated deployment of geothermal
heating & cooling across Europe. These are
to develop innovative solutions especially
Figure 1: RD&D expenditure on geothermal energy in 2011 in some European
countries (EUR million - 2012 prices and exchange rates)
20
18.2
18
16
14
12
9.8
10
8.1
8
5.7
6
4.7
4
2
0.8
0.6
0
any
rm
Ge
d
lan
zer
it
Sw
ly
Ita
Source: IEA, RD&D Statistics Database
ain
Sp
ce
n
Fra
nds
erla
th
Ne
m
lgiu
Be
0.1
0.03
ia
str
Au
and
Irel
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Geothermal RD&D spending shows major
variations among the Member States,
although some research priorities are common in some technologies among groups of
countries. Synergies should be exploited in
these areas, which are particularly important
for capital-intensive RD&D activities.
In 2011, overall public RD&D expenditure
on geothermal energy amounted to EUR 48
million, representing about 6.2 % of the total
public budget for RD&D activities in the RES
sectors for those countries analysed (Fig. 1).
Germany represents the country with the
highest public expenditure for RD&D activities in the geothermal sector by far, spending more than EUR 18 million in 2011, which
corresponds to 38 % of the total geothermal
budget for the countries under consideration.
Switzerland follows with EUR 9.8 million, then
Italy with EUR 8.1 million, Spain with EUR 5.7
million and France with EUR 4.7 million.
Until 2012, the EU RD&D funding allocated
to geothermal energy during FP6 and FP7
amounted to EUR 29.4 million which was
as much as 10 times lower than the funding
for photovoltaic (The Geothermal Technology Roadmap of the European Technology
Platform on Renewable Heating and Cooling
- March 2014). Moreover, to date the geothermal sector, together with biomass, has
experienced a proportional reduction in FP7
funding (from EUR 17.3 million in FP6 to EUR
12.1 million) (Pezzuto et al., 2012).
The NER300 programme is another financing
instrument which exists at the EU level. In the
first call, a Hungarian EGS project near Ferencszállás received EUR40 million. In the 2nd
round of the European NER300 programme
two geothermal projects were selected for
support. The first project in Croatia concerns
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the production of electricity and heat from
a geothermal aquifer and its associated
natural gas. The project, located in Draskovec, close to the city of Prelog in Croatia, will
generate 3.1 MWe from geothermal hot brine
using an Organic Rankine Cycle (ORC).
The second project is GEOSTRAS, a FrenchGerman cross-border project that aims to produce electricity and heat from a high temperature geothermal resource near Strasbourg. It
involves creating a circulation loop several
kilometres long at a depth of between 4 km
and 5 km that will function as a semi-open
underground heat exchanger. The proposed
geothermal plant is expected to produce
6.7 MWe electricity and 34.7 MWth heat.
In the context of the European Energy Research
Alliance (EERA), a main Joint Programme on
Geothermal Energy (JPGE)1 has been defined
involving a total of 420 people who have been
assigned different roles and responsibilities. The
research infrastructures are shared among the
participants and the comprehensive budget is
about EUR 30 million per year.
The main objectives of the EERA concern
increasing the contribution by geothermal
energy to global power production. The
research programme aims to:
• prepare EGS for large-scale deployment;
• enhance the production from current operational plants;
• explore on a large scale new, untapped
deep-seated (up to 6 km) hydrothermal
systems;
• access ‘high potential’ resources such as
supercritical fluids and magmatic systems.
Beside the technological challenges, other
relevant aspects for the further development
1 For further information see: http://www.eera-set.eu/index.php?index=22
Overcoming Research Challenges for Geothermal Energy
of geothermal energy need to be addressed
with innovative approaches and tools to:
• improve risk assessment and management for a reliable evaluation of the technical, environmental and economic sustainability of the projects;
• secure the social acceptance of geothermal projects by ensuring that potential
site and technology-specific side effects
are typically relatively minor compared to
the benefits;
• provide guidelines for the regulatory authorities and policy-makers for the sustainable
development of geothermal initiatives.
The JPGE will be developed over 10 years
and is divided into five sub-programmes:
•
•
•
•
Resource assessment
Exploration
Accessing and engineering of the reservoir
Process engineering and design of power
systems
• Sustainability, environment and regulatory
framework
11
Geothermal energy in
the EU Member States
National strategies for geothermal energy
in the EU Member States have a significant
impact on geothermal technology development because critical issues for technological improvement and applications are
being addressed. The cases of France, Germany, Italy and Spain have been highlighted
because these countries are very active in
this field, as shown in Fig. 1 above.
France
The National Committee for geothermal
energy was established in 2010 with the task
of promoting the development of this important renewable energy source, upon which
the country has been focusing in recent years.
The committee in question is composed of
35 experts who have already started working on three guidelines: the simplification of
bureaucracy and regulations regarding the
facilities, staff training, and information for
the general public.
Geothermal plant
in Tuscany.
© iStockphoto
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So many projects have already been completed in the country over the last 40 years
and the French objectives for geothermal
energy development in the medium term
appear to be even more ambitious: by 2020,
the production of geothermal energy will
have increased sixfold. Substantial investment has also been made available for the
creation of a network of geothermal power
plants of the last generation, amounting to
EUR 20 billion.
To date, France represents the third country per total capacity installed in the EU,
both for electricity generation (17 MW) and
direct heat use (365 GWth) from geothermal
sources. The country has two high-temperature geothermal plants, both in the overseas
territories where the highest geothermal
energy potential is to be found. In the coming years, the total capacity at the Bouillante
and Guadalupe plants is expected to reach
20 MW. In the low-and medium-energy sectors, there are about 50 plants in France
which are mainly used for district heating. In
particular, in the Paris area there are 36 geothermal doublets that are directly connected
to heating networks (IEA-GIA, 2012).
In 2011, a strategic geothermal roadmap was
published by the ADEME (the French Agency
for Environment and Energy). It describes the
challenges and issues in the geothermal sector, gives a vision for 2020, and identifies the
technical and scientific barriers to defining
R&D priorities and the need for demonstration operations. Progress varies considerably
among the various geothermal uses:
• Electricity: many projects are emerging on
the mainland (combined heat and power),
but fewer are planned for the overseas
regions, due to a less-favourable framework (notably, the feed-in tariff);
• Direct use: a few installations are built
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each year in the Paris Basin, which is
encouraging but not sufficient. To reach
the objective, the number of installations
in the Paris Basin must be increased and
other projects must be launched in a variety of aquifers and geological contexts;
• Ground-source heat pumps: the installed
capacity is growing very slowly, so the
pace must increase to reach the target.
Germany
In Germany, according to AGEE-Stat (the Ministry of Environment working group on renewable statistics), net installed geothermal
capacity increased by 4 MW in 2012 via the
new Insheim plant. The country now has seven
geothermal cogeneration plants and the geothermal electric output is reaching 35 GWh
(Agemar et al., 2014). Two more plants were
commissioned in 2013 at Durrnhaar (5.5 MW)
and Kirchstockach (5.5 MW), both in Bavaria.
Germany intends to significantly increase its
geothermal electrical capacity by an attractive feed-in tariff of €0.25/kWh over 20
years. The country plans to develop geothermal resources of about 280 MW by 2020,
compared to 12 MW currently installed. To
date, there are about ten projects under construction in Germany with a capacity of more
than 36 MW, and even more at the development stage.
From 2003 to 2013, the annual production of geothermal district heating stations
increased from 60 GWh to 530 GWh. During
the same time, the annual power production
increased from 0 GWh to 36 GWh. Currently,
almost 200 geothermal facilities are either in
operation or under construction in Germany.
Italy
It is well known that Italy is rich in geothermal
energy, and since the beginning of the last
century it has exploited this source to produce
Overcoming Research Challenges for Geothermal Energy
electricity using large plants. In addition, Italy
is one of the countries with great technological know-how in this field. The historical and
important applications of geothermal energy
are located in Tuscany. Over 30 manufacturing plants, with an installed capacity of 875
MW, an output energy of more than 5 600
GWh per year, and about 5 500 of direct and
indirect jobs, represent about a quarter of the
electricity consumed in the region itself, and
nearly 2 % of the national supply. All activities aimed at growing geothermal electricity
production are made by the national electric
company Enel. Geothermal energy has great
potential for development and may allow the
country to reach the target of 25 % of energy
produced from clean sources more easily. At
present, geothermal energy supplies 10 % of
electrical energy from renewable sources and
with the new legislative tools is expected to
double within a short time (UGI, 2011).
In the Italian legal system, geothermal energy
does not belong to the landowner but is the
exclusive heritage of the state, like mineral
resources. Consequently, geothermal exploitation requires a public concession. With the
launch of the legislative Decree No. 22 of
11 February 2010, the rules for obtaining the
necessary permits for the implementation of
geothermal resources development projects
for energy purposes, in particular, have been
simplified. In this legislative decree, particular emphasis was placed on the production
of geothermal energy for non-electric uses
and introduced a special and innovative discipline related to geothermal heat pumps.
Such technology, with or without the extraction of water from the shallow subsoil, can be
exploited in areas not characterised by high
geothermal gradients.
Spain Cercs
thermal plant
chimney.
© iStockphoto
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The applications of geothermal energy used
by private citizens – heating and cooling of
buildings, greenhouses and sports facilities – are regulated by simplified forms of
authorisation comprising incentives provided
for renewable energy and energy efficiency.
In this way, it should be possible to stimulate the use of geothermal technologies
and, thus, development of the geothermal
industry.
As far as RD&D is concerned, an important
project for geothermal energy exploitation –
the Campi Flegrei Deep Drilling Project – has
been launched in the suburban area close to
Naples. This area is characterised by temperatures of about 150 °C at some hundred
metres and has huge potential for heat supply and electricity production.
Spain
The estimated geothermal potential for
electricity production (conventional and new
EGS) is close to 3 000 MWe. There has been
an increasing trend in renewable energies in
Spain over the last decade. In 2013, primary
energy consumption of renewable energy
reached 17 million toe (14.2 % of the total
energy mix) and 7.5 % higher than the previous year (IDAE, 2013). This trend has been
seen as an example of successful policies to
promote renewables energies. In 2013, the
electricity generated from renewable sources
accounted for 33.5 % of gross electricity consumption in Spain (Eurostat database).
Despite the importance of Spanish geothermal resources, the importance of geothermal energy is low, notwithstanding the very
large number of studies and investigations
conducted up until the end of the 1980s.
However, recently, there has been renewed
interest in geothermal exploitation. Currently in Spain there are no high-enthalpy
geothermal plants for electricity generation,
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although there is a large and growing interest in developing such projects in the short
to medium term.
Therefore, for deep geothermal energy the
technological challenge is to find ways of
using existing geothermal resources in a
technically and economically viable manner,
which is only possible via the technological
development of new drilling methods for
reducing costs and stimulating wells.
At the end of 2012, the installed capacity
of shallow geothermal energy was 50 MWth
(EGEC, 2013). Spain’s target for geothermal
heat use, in the decade from 2011-2020,
has been fixed at 50 ktoes, to be achieved
by using direct thermal applications and
heat pumps. Studies on geothermal district
heating development are ready to begin, and
there are several projects for district heating
networks in Madrid, Burgos and Barcelona,
for example. However, some of these projects are at the initial geothermal exploration phase.
Geothermal strategies
in non-EU countries
Over the next few years, global growth is
expected in geothermal energy, according
to the most recent report by the Geothermal
Energy Association (GEA) on the global geothermal market, which estimates the current
installed geothermal capacity worldwide at
11 772 MW. According to the Renewable
Energy Policy Network’s Renewables 2013
Global Status Report, the United States is
leading the installed generating capacity in
the world with 3 400 MW, followed by the
Philippines (1 900 MW), Indonesia (1 300
MW), Mexico (1 000 MW), Italy (900 MW),
New Zealand (800 MW), Iceland (700 MW)
and Japan (500 MW).
Overcoming Research Challenges for Geothermal Energy
It is important to point out the increase from
30 to 64 in the number of countries which
are showing an interest in the development
and applications of geothermal energy. This
increase depends on several factors which
are mainly related to the discovery of new
resources, technological improvements
in exploration and the ability to exploit
resources in the medium- and low-enthalpy
range at greater depths, together with the
opening up of new prospects and markets
besides the traditional ones.
In the near future, the United States will
be the country making the greatest effort
in this field, followed by certain countries in
the Pacific area, such as Indonesia which,
considering its huge theoretical geothermal
potential of 28 000 MW, aims to produce
more than 9 000 MW of geothermal power
by 2025, thereby becoming the world’s leading geothermal energy producer.
Recently, China has expressed a great interest in geothermal energy with the aim of
using this resource to cover 1.7 % of primary
15
energy demand by 2015, as reported by the
Ministry of Land and Resources. The goal is
to replace the use of 68.8 million tonnes of
coal and reduce 180 million tonnes of carbon
dioxide emissions. In the field of spa tourism, this resource is already widely used in
some regions, especially in the province of
Chongqing (south-west China), where there
are 107 thermal sites. Currently in China,
geothermal explorations are under way in
29 provinces, with public funding for research
activities alone in 2011 reaching 164 million
yuan (EUR 17 million). The objective is to provide systems for the production of electricity
across the country
In Canada, the largest conventional resources
for geothermal power are located in British
Columbia, Yukon and Alberta, regions which
also have the potential for EGS exploitation.
In 2007, it was estimated that geothermal
energy could meet half of British Columbia’s
electricity needs. Canada officially reports
about 30 000 earth-heat installations providing space heating to residential and commercial buildings. The most advanced project
Cogeneration
in China.
© iStockphoto
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In Switzerland, 22 deep geothermal projects
are currently at the planning stage, their
main objective being to produce electricity.
Nevertheless, in July of 2013, earthquakes
of magnitude 3.5 in Basel and St Gallen,
produced by an unexpected encounter of
gas at a depth of 4450 m, have significantly
reduced the population’s confidence in EGS
geothermal plant development.
Geothermal plant
in California.
© iStockphoto
exists as a test geothermal electrical site in
the Meager Mountain-Pebble Creek area of
British Columbia, where a 100-300 MW facility could be developed.
An important contribution could also come
from South American countries, where there
is large geothermal potential along the
Andean Ridge and on the Central Pacific side.
Ecuador has announced feasibility studies to
analyse the country’s geothermal potential.
The government has announced five projects
that will exploit geothermal energy – the total
potential has been estimated at > 500MW –
the aim being to increase the percentage of
energy from alternative sources. Pre-feasibility studies to the value of 1.1 million dollars
have been planned in Carchi province where
the potential has been estimated at between
60-130 MW. However, the number of projects remains limited and those that could be
accomplished relate mainly to the policies of
foreign companies that have been awarded
concessions for exploitation.
Africa has huge geothermal potential, mostly
unexplored, that has attracted the interest
of many countries in geothermal resources
development. Potential areas are: the
Republic of Congo, Eritrea, Ethiopia, Kenya,
Madagascar, Malawi, Mozambique, Rwanda,
Tanzania, Uganda and Zambia with an estimated potential greater than 15 GW. In Ethiopia, where it is up to 5 GW, the government
is aiming to increase the power developed
with the help of foreign sponsors such as the
World Bank. However, the most promising
geothermal area in Africa is in the Rift Valley
where Kenya is planning the construction of
a number of plants although it is not known
when they will become fully operational.
In Australia, the government has provided
research funding for the development of
EGS technology. One of the most important
projects in the world is being developed in
Australia’s Cooper Basin by Geodynamics.
The Cooper Basin project has the potential
to develop 5 000-10 000 MW. Australia now
has 33 firms involved in exploration, drilling
and EGS project development. The country’s
industry has been helped significantly by a
national Renewable Portfolio Standard of
25 %, renewable by 2025, a Green Energy
Credit market, and supportive collaboration
between government, academia and industry.
Overcoming Research Challenges for Geothermal Energy
Research areas
and opportunities
The main research areas and applications
contributing to geothermal energy development and deployment are:
•
•
•
•
•
exploring and drilling technologies
electricity production
heating and cooling
desalination
environmental impact mitigation and public acceptance.
Exploring and drilling
technologies
The main goal is to greatly improve modelling techniques for assessing the geothermal potential, to reduce drilling costs and
the number of boreholes that are very costeffective.
For the same reason, in the assessment of
geothermal resources, research and exploration synergies with the oil and gas industries
should be considered.
New drilling technologies should be developed to reduce costs and drilling times. In this
context, it is also necessary to improve and
develop new 3D models of geothermal reservoirs to reduce drilling and exploitation risks.
Drilling typically accounts for 30-50 % of the
total development cost of electricity generation. For example, two boreholes to a depth
of 3 000 m. can cost up to EUR 14 million,
while piping costs vary from EUR 200 to EUR
6 000 million in urban areas.
Improving drilling technologies and modelling accuracy to better estimate geothermal
potential are crucial steps for assessing the
cost and investment time return. Experience suggests that this is the way to greatly
improve geothermal energy development.
Electricity production
Nowadays, there are about 12 000 MW of
geothermal power plant installed capacity in
the world and 1 700 MW of geothermal power
under construction. However, these data represent a small fraction when compared to the
data for wind energy (320 000 MW) and photovoltaic (140 000 MW). The average annual
growth rate for electricity produced from geothermal heat is 5 %, which is much lower than
wind and solar electricity (20-30 %).
The electricity produced by geothermal heat
using new technological approaches such as
EGS does not attract significant investments
in RD&D from large energy companies in
relation to actual electricity surplus in industrialised countries. This overproduction is the
consequence of both the economic crisis and
the concomitant expansion of solar and wind
energy, which are the most convenient clean
energies requiring only a short time for implementation. In addition, EGS power plant is
still in the prototype stage and a further step
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lenges facing deep geothermal exploitation.
RD&D activities are required in new materials
and operational methods, bearing in mind the
significant impact of scaling and corrosion on
the cost and efficiency of geothermal technology. The development of new components
from polymers or plastics, optimised coating,
the use of aluminium, and new materials to
tackle deterioration resulting from UV exposure should all be taken into account.
towards large-scale demonstration plant is
crucial, as is the reduction of costs and time
for geothermal power plant construction.
Compared to other technologies in Europe,
asset financing for geothermal energy is
quite low: EUR 124 million for a new capacity
of 34 MW. Furthermore, scaling and corrosion
represent one of the most important chal-
It is also important to remember that startup costs are relatively high: an average geothermal plant costs EUR 3 500 per kilowatt
(kW) installed versus EUR 1 200 per kW
installed for a natural gas plant. A conventional 20 MWe high-temperature plant costs
EUR 80-120 million and a 5 MW EGS plant
costs EUR 35-65 million.
The most important RD&D project on EGS
to be launched by the EU was carried out at
Soultz-Sous-Forêts in France where it has
recently connected its 1.5 MW demonstration plant to the grid. The surface geothermal
Table 3: Main EGS research projects in the world
Project
Country
MW
Plant Type
Depth (km)
Soultz
France
1.5
ORC
5.0
Landau
Germany
3.0
ORC
3.0
Insheim
Germany
4.8
ORC
3.6
Unterhaching
Germany
3.0
Kalina
3.5
Desert Peak
U.S.A
1.7
Binary
4.0
Paralana
Australia
3.8
Binary
4.0
Cooper Basin
Australia
25.0
Kalina
4.0
Hijiori
Japan
0.13
Binary
1.1
Redruth
U. K.
10.0
Binary
4.5
Eden
U.K.
4.0
Binary
3/4
Source: Data collected from the Geothermal Energy Journal and other sources
Overcoming Research Challenges for Geothermal Energy
energy installations in this pilot scientific project, which started 20 years ago, have been
supplying power to the grid continuously for
a year, following the introduction of the new
feed-in tariff in July 2010.
sustainability of the operation. The aim is to
identify the circulation routes between the
wells (by improving tracer tests and circulation modelling) and to understand how they
evolve during operations.
The Soultz project has explored the connection of multiple stimulated zones and
the performance of triplet-well configurations (one injector/two producers). This pilot
project, which draws on heat sources (up to
200 ºC) from 4 500 to 5 000 m deep, operates on a binary cycle principle ORC (Organic
Rankine Cycle). The hot fluid arriving at the
wellhead circulates in a closed loop and
passes through a heat exchanger which
transfers heat to an organic fluid with a lower
boiling point which allows it to drive a turbine. Having contributed to scientific work on
well stimulation with a view to developing
the site, in parallel with its operations related
to the European Economic Interest Group
(EEIG) on Heat Mining, the BRGM (Bureau
de Recherches Géologiques et Minières),
financed by ADEME, is now working on the
Recently, in the field of low and middle enthalpy, a new application called the
‘Green Machine’ has been developed to
produce electricity. This machine exploits
the ORC technology and is able to produce
energy by heat sources at low temperatures,
mainly between 77 °C and 116 °C. The mini
and micro sizes in which ORC technology is
provided by the Green Machine allow flow
rates to be converted at low temperatures in
renewable electricity with zero CO2 emissions
in a range of nominal electric power from 20
to 110 kWe. It requires little space, thanks
to its very compact dimensions and different options for installation. To summarise,
the Green Machine is an apparatus with a
versatile technology which is mainly devoted
to the exploitation of low-temperature geothermal systems2.
19
Geothermal
power station
in Iceland.
© iStockphoto
2 See http://electratherm.com/case_studies/
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Heating and cooling
In Europe, the geothermal heating sector
is led by Germany and Sweden, although
in Austria, Finland and France the installed
capacity of geothermal heat pumps is considerable.
Residential and commercial heating may
be a more profitable option both in timing
and costs with respect to the generation of
electricity because these technologies are
already competitive from the commercial
standpoint. Within this sector there are no
large research projects but mainly a minor
upgrading of current technologies. According
to the industry association (European Heat
Pump Association – EHPA), the total number of geothermal heat pumps installed in
Europe from 1998 to 2012 was about 1 million units.
District heating
in Vienna.
© iStockphoto
K n o w l e d g e
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There are two options in the heating sector:
heating through deep wells with a distribution network for neighbourhoods (centralised
heating with direct uses, also known as district heating), and heating/cooling through
geothermal heat pumps for single buildings
or residential centres.
Centralised heating exploits the deep wells
to extract hot water which is then distributed
to the neighbourhoods via a district heating
network. The most interesting examples are
found in Ferrara, Oradea (Romania), Paris and
Reykjavík. This type of geothermal application presents some technical and social problems because it requires the involvement of
local authorities which should provide the
necessary authorisation. Delays may be
caused because the building of the district
heating network and infrastructure is a complex task that can create considerable inconvenience for the resident population.
Overcoming Research Challenges for Geothermal Energy
Residential heating may be more easily
achieved by small enterprises, especially
when new buildings are planned and geothermal probes can be associated with the
foundations. The best technologies are those
that exchange the heat through a liquid in a
closed circuit. This approach avoids direct liquid interaction with the groundwater, thereby
greatly reducing the environmental impact.
It can also be applied to old buildings which
have to be restructured. In this case, fan coil
heat pumps could be more convenient.
To promote the development of residential
geothermal heating without water exchange,
it is essential that the geothermal installations
do not require any permission. In fact, restrictions like those required for well drillings could
be an obstacle to the growth of this technology which works as a closed loop system and
does not involve water exchange. Financial
incentives should be considered for new buildings to improve the use of this technology.
Financial incentives to improve geothermal
technology applications for the residential
sector could drive demand and thus growth
of the production sector related to these technologies. To date, it could be possible to set in
motion an innovative mechanism that would
push producers to achieve increasingly efficient technologies at a lower cost to meet the
growing demand. To support such a mechanism it might be very useful to implement a
special industrial incentive law which allows
the buyer to pay for the new technologies in
instalments at a subsidised interest rate and
enables the seller to receive all the payments
immediately from the authorised bank. In
other words, it is crucial to establish a connection among producers, buyers, government
and banks with the aim of setting in motion
a virtuous interaction that can stimulate a
large diffusion and innovation processes in
residential geothermal technologies.
21
Desalination at
Trapani in Sicily.
© iStockphoto
Desalination
Seawater desalination by geothermal heat
plants represents a new and interesting
perspective to enable volcanic islands to
achieve greater energy independence. In
Europe, most of the Mediterranean islands
can be identified as volcanic islands with high
geothermal gradient
A successful demonstration of the application
of geothermal to desalination was provided
by the European Commission research project
THERMIE.GE.438.94.HE, known as the Kimolos
project. The pilot project (1994-1999) used a
low-enthalpy geothermal energy source with
the aim of verifying the technical feasibility of
seawater desalination.
The Multi-stage distillation process (MED)
was selected for this project because it needs
less energy compared to other technologies,
requires working temperatures of <70 °C and
low vessel pressure. In addition, the feed
water forms a thin film layer that reduces
the formation of scaling. The water produced
is of good quality as testified by the result-
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ing salinity which is less than 10 ppm. This
technology is also energy efficient because
the heat released by condensing vapour is
utilised to boil feed water, too. Compared
to Multi-stage-flash distillation (MSF), it is a
cost-saving technology which produces fresh
water and requires fewer stages.
K n o w l e d g e
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hazardous to the environment. For these reasons it is necessary to put greater effort into
developing new technologies and systems to
remove the solid residues and condensable
gases associated with geothermal fluids.
Environmental impact
mitigation and public
acceptance
In relation to EGS, it is also important to
consider the seismic activity induced by this
technology. The critical issue is to obtain
the acceptance of the general public. Earthquakes triggered by rocks fracturing should
be reduced as much as possible, and experience shows that public acceptance can only
be achieved if the population is involved in
all stages of the procedure. For example,
in St Gallen, Switzerland, the government
has given advanced warning and informed
the public about the possible risks linked to
the construction of an EGS plant. Following
a low-intensity earthquake related to the
application of EGS technology, the authorities compensated residents for any damage
and, following a discussion with the public,
secured the authorisation to proceed with
geothermal exploitation.
Although geothermal energy is regarded as
a source of energy with a low level of polluting emissions compared to traditional energy
sources, geothermal fluids, especially those
at medium and high temperature, contain
some potentially toxic elements such as
mercury (Hg), arsenic (As) and gases such as
hydrogen sulphide (H2S), which could prove
To summarise, gas emissions and micro-seismicity are factors that reduce public confidence towards geothermal development.
So, it remains worthwhile to fully assess the
social and environmental impact of the activities, to develop new tools for analysis, and
to inform the population in order to achieve
greater public acceptance.
It would appear that the potential of lowenthalpy geothermal energy for desalination
via MED is significant and many countries
are now showing interest in this technological option. Among others, Middle Eastern
countries, Algeria, Australia and Mexico have
considered the possibility of exploiting lowenthalpy geothermal energy for desalination
even if this process has yet to be developed
significantly on a commercial scale and technical design problems and high investment
costs have still to be overcome.
Overcoming Research Challenges for Geothermal Energy
23
Looking to
the future
The most recent SET-Plan integrated roadmap3 pays special attention to the Smart Cities Initiative which aims to improve energy
efficiency and to deploy renewable energy
in large cities above and beyond the levels
envisaged in the EU’s energy and climate
change policy. This initiative will support
cities and regions in taking ambitious and
pioneering measures to progress by 2020
towards a 40 % reduction in greenhouse
gas emissions through the sustainable use
and production of energy. Geothermal heat
exploitation may provide an important contribution to the Smart Cities Initiative.
In the geothermal heat-pump sector, the
RD&D priorities are to maximise efficiency
(coefficient of performance – COP, and seasonal performance factor – SPF) and reduce
costs. The focus is on developing components
that are easy to connect and disconnect from
the surface, as well as advanced control
systems, natural and more efficient working
fluids, single-split and multi-split heat-pump
solutions for moderate climate zones, and
the increased efficiency of auxiliaries, such as
pumps and fans. The key component areas
are heat exchangers, compressors, fans and
pumps, expansion valves, defrosting strate-
Iceland’s
geothermal
plant in the Krafla
volcanic region.
© iStockphoto
3 http://setis.ec.europa.eu/set-plan-implementation/technology-roadmaps/european-initiative-smart-cities
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gies, and new materials. In order to reach
maximum efficiency, these advanced components should be perfectly designed into one
system and controlled and operated by smart
systems, including automatic fault detection
and diagnostic tools, too.
For relevant growth in RD&D investment for
new geothermal technologies for electricity
production (EGS) it will be essential to adopt
effective policies to stimulate innovation and
experimentation by launching new demonstration projects. This implies a qualitative
leap in government and banking systems as
well as the involvement of large corporations which should play an active role in the
network of universities and public research
centres. The main efforts should focus on
lowering the cost of exploration and drilling,
reducing the time and costs involved in power
plant constructions, optimising efficiency, and
increasing the longevity of installations.
Scaling and corrosion represent one of the
most important challenges facing deep geothermal exploitation. RD&D activities are
required for new materials and operational
methods, bearing in mind the significant
impact of scaling and corrosion on the cost
and efficiency of geothermal technology.
The development of new components from
polymers or plastics, optimised coating, the
utilisation of aluminium, and new materials to tackle deterioration resulting from UV
exposure should all be taken into account.
Since deep geothermal fluids contain some
potentially toxic elements, such as Hg, As
and gases like H2S, which could damage the
environment, it is necessary to carry out further and advanced research to develop new
technologies and systems able to remove the
K n o w l e d g e
C e n t r e
solid residues and condensable gases associated with geothermal steam.
Future research programmes will increasingly focus on offshore and magmatic geothermal energy exploitation. In fact, most
of the areas with the highest geothermal
potential are located at sea where geological frameworks characterised by high geothermal gradients (> 100 °C/km) are diffused.
In particular, supercritical fluids are present
in the deep ocean surface in sub-marine
volcanic areas. The main research challenge in this field is to develop technologies
to exploit these supercritical fluids at high
temperatures in deep marine environments
in order to exploit the enormous geothermal
sub-marine reservoirs.
In this respect, the first offshore geothermal
project has been proposed in Italy to exploit
the heat produced by the sub-marine volcano
Marsili, located in the southern Tyrrhenian
Sea, close to the Aeolian Islands’ volcanic arc.
The project has been developed by a private
company, Eurobuilding, in collaboration with
certain Italian public research centres and
universities.
In 2009, the Marsili project received the
approval of the Italian Ministry of Economic
Development. The Marsili volcano is the largest volcanic structure in Europe and releases
fluids at high temperatures, around 300 °C.
When fully operational, the plant will produce
4.4 billion kWh per year4.
In Iceland – a country where approximately
87 % of the houses are heated using geothermal energy and 27 % of the electricity
comes from this energy source – a project
is being carried out which aims to produce
4 For further information see:
http://www.senato.it/documenti/repository/commissioni/comm10/documenti_acquisiti/IC%20strategia%20
energetica/2011_10_28-Eurobuilding.pdf
Overcoming Research Challenges for Geothermal Energy
energy from magma rather than from solid
rock: the ‘magma enhanced geothermal system’ (Elders et al., 2014). Scientists from the
Iceland Deep Drilling Project (IDDP), which is
owned by the National Energy Authority of
Iceland (Orkustofnun), and other public and
private companies are working on this project.
Magma exploitation started a few years ago
during the drilling of the Krafla caldera by
IDDP in the north-east of Iceland. The sensors
evidenced an area had been struck which had
a temperature of 1 000 °C, producing huge
steam vents with temperatures around
450 °C. The team was astonished to discover
that a magma chamber 5 km below the Earth
surface was drilled through. Therefore, it was
possible to use the heat to generate 36 MW
of power, giving rise to the first geothermal
energy system based on magma as direct
source. The well, about 2 km deep, is known
today as IDDP-1 and is located near the Krafla caldera. By this chance of direct magma
exploitation, Iceland hopes to improve the
geothermal energy production. This project
would be an important step towards the
development of high-temperature geothermal resources.
25
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Policy implications
and recommendations
Considering the low financial interest shown
by large electricity companies in the exploitation of deep geothermal energy for electricity production in Europe, it is crucial that
governments aggregate consortia of large
corporations, small and medium-sized enterprises and universities around large research
projects and provide public funds to promote
electricity production by means of deep
large-scale demonstration projects. (According to the 13th EurObserv’ER Report in 2012,
there was a drop in both total asset financing and the number of projects: investments
fell by almost 34 % from EUR 190 million in
2011 to EUR 124 million in 2012.)
tion from a commercial standpoint because
competitive technologies are already available and there are no significant barriers to
implementing such technologies. As regards
heating and cooling, it is important to create
financial incentives and legislative rules in the
new construction market for the use of geothermal technologies (“demand pull” policies)
in order to stimulate the applications and diffusion mechanism and subsequently growth
in production and innovation processes by
those industrial firms producing geothermal
heat pumps. Furthermore, it is essential to
reduce permissions and authorisations so as
to liberalise heat pump installations.
In Europe, the most suitable areas for geothermal energy for electricity production are
in Greece, Hungary, Italy and Romania: since
high geothermal anomalies are located in
these countries EGS research projects should
be focused on these high-geothermal gradient areas.
In conclusion, the key barriers to larger geothermal energy exploitation for electricity
production are the high costs of drilling and
power plant construction, the long period
for developing deep geothermal projects to
commercial deployment, and the risk that
electricity production will not reach the projected objectives. Success ratios for both
exploration and production wells remain low.
Future research activities should address
reducing risks by improving approaches to
exploration and better mapping and modelling. Furthermore, fragmentation of existing
knowledge is limiting progress in the sector while technological and environmental
knowledge gaps increase the financial risk.
Actions to share existing knowledge, also
with other sectors (for instance, oil and gas
exploration) are crucial for the future development of geothermal energy exploitation.
The Mediterranean volcanic islands represent
special consideration because they could
achieve greater energy independence by
implementing geothermal technologies for
desalination, heating and cooling and, where
possible, for electricity production. A pilot project for a selected island could be launched in
order to assess the possibility of repeating it
in other EU islands.
Heating and cooling for residential buildings
is the most interesting geothermal applica-
Overcoming Research Challenges for Geothermal Energy
For all these reasons it is essential to move
to a full-scale demonstration level of EGS
plants.
Last but not least, gas emissions and microseismicity are factors that reduce public
27
confidence in EGS development. Therefore, it
is worthwhile to fully assess the social and
environmental impact of such activities by
developing new tools for analysis and involving the population in geothermal projects in
an effort to achieve wide public acceptance.
Interior chimney
looking skywards.
© iStockphoto
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Rafferty, K. (1997), An information survival kit for the prospective residential geothermal heat
pump owner, Bull. Geo-Heat Center, 18, 2, pp. 1-11.
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K n o w l e d g e
C e n t r e
Renewable Energy Policy Network’s Renewables 2013 Global Status Report.
Sören, R., Kölbel, T., Schlagermann, P., Pellizzone, A., Allansdottir, A. (2013), Public acceptance
of geothermal electricity production. Deliverable n° 4.4 Report on public acceptance: April
2013.
Seyboth, K., Beskens, L., Langniss, Sims, R. E.H. (2008), “Recognising the potential for renewable energy heating and cooling”, Energy Policy 36, pp. 2460-2463.
Stanford University (2010), Proceedings 35th Stanford Workshop on Geothermal Reservoir
Engineering.
Stefansson, V. (2000), The renewability of geothermal energy. Proceedings World Geothermal
Energy, Japan.
UGI (2011), Previsione di crescita della geotermia in Italia fino al 2030.
Wright, P.M. (1998), The sustainability of production from geothermal resources, Bull. GeoHeat Center, 19, 2, pp. 9-12.
Overcoming Research Challenges for Geothermal Energy
Selected websites on
geothermal energy
www.energies-renouvelables.org/observ-er/stat_baro/barobilan/barobilan13-gb.pdf
www.iea.org/topics/geothermal/
thinkgeoenergy.com/archives/8043
www.geothermal-energy.org/
www1.eere.energy.gov/library/viewdetails.aspx?productid=6126&page=4
www.unionegeotermica.it/
www.egec.org/
www.vigor-geotermia.it/
www.gshp.org.uk/gshp.htm
www.thermogis.nl/worldviewer/ThermoGISWorldEdition.html
www.eera-set.eu/index.php?index=22
mitei.mit.edu/publications/reports-studies/future-geothermal-energy
www.heatflow.und.edu/index2.html
www.geo-energy.org/
energy.gov/eere/renewables/geothermal
www.geotis.de/
www.geothermal-energy-journal.com/content/1/1/4
www.iea.org/files/ann_rep_sec/geo2010.pdf
www.geoplat.org/setup/upload/modules_en_docs/content_cont_URI_702.pdf
www.eurobuilding.it/index.php?option=com_content&view=article&id=61&Itemid=93
www.rhc-platform.org/fileadmin/Publications/Geothermal_Roadmap-WEB.pdf
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List of Acronyms
ADEME
AGEE-Stat
As
BRGM
COP
ECN
EEIG
EERA
EGS
EHPA
Enel
ERKC
EU
FP
GDP
GEA
GHP
GWe
HC
French Agency for Environment and Energy Management
Germany Ministry of Environment Working Group on Renewable
Energy Statistics
Arsenic
Bureau de Recherches Géologiques et Minières
Coefficient of Performance
European Competition Network
European Economic Interest Group
European Energy Research Alliance
Enhanced Geothermal System
European Heat Pump Association
Ente Nazionale per l’energia ELettrica
Energy Research Knowledge Centre
European Union
Framework Programme for Research and Technological Development
Gross domestic product
Geothermal Energy Association
Geothermal Heat Pumps
Gigawatt (electric)
Heating and cooling
Overcoming Research Challenges for Geothermal Energy
H2S
Hg
IDDP
IEA
JPGE
kW
ktoe
MED
MSF
MWe
NREAP
ORC
R&D
RD&D
SET-Plan
SETIS
SPF
TP Geoelec
TP HC
TWh
Hydrogen sulphide
Mercury
Iceland Deep Drilling Project
International Energy Agency
Joint Programme on Geothermal Energy
kiloWatt
thousand tonnes of oil equivalent
Multi-effect distillation
Multi-stage-flash distillation
Megawatt (electric)
National Renewable Energy Action Plan
Organic Rankine Cycle
Research and development
Research, development and demonstration
European Strategic Energy Technology Plan
Strategic Energy Technologies Information System
Seasonal performance factor
European Technology Platform on Geothermal electricity
European Technology Platform on Heating and Cooling
TeraWatt hours
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Residential and commercial heating may be a more
profitable option, both in timing and costs, for electricity generation because these technologies are
already competitive from the commercial standpoint.
Financial incentives to improve geothermal technology applications for the residential sector could drive
demand and therefore growth of the production
sector. In addition, it is essential that geothermal
installations do not require permission.
For the relevant growth in RD&D investment in new
geothermal technologies for electricity production
it will be essential to adopt effective policies to
stimulate new demonstration projects and largescale deployment.