geothermal activities in greece

Transcription

GEOTHERMAL ACTIVITIES
IN GREECE
Dr. Apostolos Arvanitis
Division of Geothermal Energy and Thermal Mineral Waters,
Institute of Geology and Mineral Exploration (I.G.Μ.Ε.),
1, Sp. Louis st., Entrance C, Olympic Village, 13677, Acharnae, Attica, GREECE
International
Trade Fair
Energy 2011
Renewable Energy Industry and Export Forum
4 - 8 April 2011, Hannover, Germany
Geothermal exploration in Greece
Geothermal exploration in Greece
began in the early 1970s by
I.G.M.E.
Greece is rich in geothermal
energy resources.
The Hellenic area is characterized
by high levels of heat flow
(> 80 mW/m2), mainly in the
sedimentary basins of
Northeastern Greece and the
Aegean Sea, due to the active
tectonics and the volcanic activity.
The very intense volcano-tectonic
activity caused the geological
conditions for accumulation of
heat energy which is manifested
in many places as hydrothermal
systems of low-medium and high
enthalpy geothermal fields.
Geothermal areas in Greece with main
geotectonic structures
Preliminary map of heat flow density (Fytikas &
Kolios, 1979)
Areas of increased heat flow are:
Map of heat flow density in Greece (I.G.M.E., 2001)
9 South Aegean Volcanic Arc (Methana, Sousaki, Milos, Nisyros, Santorini, Kos)
9 Sedimentary basins of Northern Greece (Strimon river basin, Delta Nestos basin, Delta Evros basin)
9 Northern Evia (Euboea) (Aedipsos area) - Sperchios basin
9 Islands in east Aegean sea: Samothrace, Lemnos, Lesvos, Chios, Ikaria.
High enthalpy geothermal fields in Greece
The most important high enthalpy
geothermal fields (Milos, Nisyros)
are located in the Southern Aegean
along the active volcanic arc
(SAAVA) with proven geothermal
potential 25 MWe and estimated
possible potential >250 MWe.
The South Aegean Active Volcanic Arc and
the locations of Milos and Nisyros islands
High enthalpy geothermal field
of Milos island
Five geothermal wells (1,017-1,381 m
deep) were drilled on Milos island
during 1975-1981
Temperature in the wells: 280-325οC
Depth of reservoir: 1,000-1,380 m
Production: 339 t/h of fluids
(200 t/h saturated steam - 139 t/h hot
water),
Pressure: 11-19 atm
High enthalpy
geothermal field
of Nisyros island
It is located in the caldera in the
central part of the island.
Two wells (1,816 and 1,547m deep)
were drilled in the early 1980’s.
Area of the field: 3.5 km2
Temperature in the wells: ~ 350οC
Depth of reservoir: 1,400-1,900 m
Production: 75 t/h of fluids
Conceptual geothermal model of the Nisyros high enthalpy geothermal field
[by Swiss Federal Institute of Technology (ETHZ)]
Ratio of steam to water 27:73
Pressure: 12 atm
Geothermal well in Nisyros
Geothermal well NIS-1 (1,816 m deep)
Medium - low enthalpy
geothermal fields
in Greece
9 Medium and low enthalpy
geothermal fields are mostly
associated with grabens and
post-orogenic sedimentary
basins.
9 There is a high potential in the
areas of Kimolos, Polyegos,
Northern Evia (Aedipsos),
Lesvos, Chios and
Samothrace islands and in the
NE continental mainland.
9 The deep water circulation
along ‘open’ faults in grabens
all over the country has
created a large number of low
enthalpy (T≤90oC) fields.
9 There are > 750 thermal
springs and > 50 spas in
operation.
9 The thermal potential of low
enthalpy geothermal
resources in Greece exceeds
1,000 MWt.
GEOTHERMAL
AREAS IN
GREECE
Some important low enthalpy geothermal fields in Greece (i)
Geothermal field of Aristino (Thrace, NE Greece):
Water temperature: 30-90oC
Depth of reservoir: 150-450 m
Discharge (from existing wells): 200 m3/h
Chemical composition of waters: Na-CI
with TDS of 4.3-10.5 g/l
Hydrothermal model of the Aristino field
Geothermal field of Nea Kessani (Thrace):
Discharge (from existing wells): >300 m3/h
Chemical composition of waters: Na-CI/ΗCO3
Geothermal well in
the Nea Kessani
field
Geothermal field of Neo Erasmio - Magana (Thrace):
Chemical composition of waters: Na-CI and
Na-ΗCO3CI with TDS of 0.57-10.1 g/l
Geothermal well and pumping station in the Neo Erasmio field
Some important low enthalpy geothermal fields in Greece (ii)
Geothermal field of Eratino - Chrysoupolis
(Eastern Macedonia, Northern Greece):
Water temperature within the reservoir: 75oC
Geothermal production wells N-1P and N-2P in the Eratino field
Geothermal field of Akropotamos (Kavala,
83oC + CO2 150 m3/h
90oC + CO2 200 m3/h
Eastern Macedonia, Northern Greece):
Depth of reservoirs: 100-185 m, 240-515 m
Chemical composition of waters: Na-CI &
Na-HCO3CI with TDS of 2.15-30.7 g/l
AKR-1
Geothermal field of Therma - Nigrita
(Serres, Central Macedonia, Northern Greece):
Discharge:
~1,000 m3/h
Chemical composition of waters:
Na-HCO3 with TDS of 1.1-3.6 g/l
3.5-4.7 kg CO2 / m3 geothermal water
Geothermal wells
AKR-1 and AKR-3
in the Akropotamos
field
Geothermal
wells in the
Therma
Nigrita
field
AKR-3
Some important low enthalpy geothermal fields in Greece (iii)
Geothermal field of Soussaki (Corinth,
Peloponnese, Southern Greece):
Reservoirs: 50-290 m T=60-78oC
600-900 m T up to 75oC
Discharge: 600 m3/h
Gases: CO2, H2S
Geothermal wells in the Soussaki field
Geothermal field of Nenita (Chios island):
Water temperature within the reservoir: 78-82.8oC
Discharge (from the existing production well): ~ 150 m3/h
with TDS of 74-74.6 g/l
Geothermal well in the Nenita field
Geothermal area of Aedipsos (Northern Evia island):
In the Aedipsos area, an exploration borehole
was drilled down to 374 m depth with a casing down
to 340 m and the maximum temperature of 80ºC
was recorded at 350 m .
Aedipsos (Northern Evia)
Some important low enthalpy geothermal fields
in Greece (iv)
Geothermal fields / areas on Lesvos island:
Geothermal field /
area
Area
(km2)
Depth of
reservoir (m)
Discharge
(m3/h)
Temperature
(°C)
Polichnitos
10
50-200
300
65-95
Stipsi
20
150-220
---
~ 90
Argenos
4
10-150
300
90
Kalloni
10
50-200
300
25-30
Thermi - Geras
>2
20-80
150
40
Argenos
10-50
200
60
Polichnitos
Thermi
Mytilene
10
50-150
500
30-35
Petra - Mithimna
10
100-200
100
35-60
20
68
Lisvori
More recently, in the broader area of Stipsi 3 exploration boreholes
were drilled by PPC. Borehole S-1 reached a depth of approximately
1,400 m and found fluids at 80ºC. Wells STE-1 and STE-2 were
drilled down to 350 and 1,000 m revealing temperatures of 106ºC
and 101ºC respectively.
Some important low enthalpy geothermal fields in Greece (v)
Geothermal area of Therma (Samothrace island):
- Thermal springs in the Therma area (T=35-58oC)
- Three shallow wells S-1, S-2 and S-3 at depths
of 120, 120 and 60 m respectively were drilled
within the thermal area near existing spas.
They yield a high flow rate of fluids and water
temperature up to 99.4oC.
- The hot waters are of Na-Cl type with high TDS
values (up to 31 g/l) and rich in Na+, CI-, Ca2+, Li+,
Sr2+ , SiO2, B, Br- and I- contents.
Geothermal well
S-3 in Therma
(Samothrace
island):
Depth: 60 m,
T=99oC
Prospective medium enthalpy geothermal resources in Greece
Favorable areas for probable existence of medium enthalpy geothermal
resources are as follows:
- The sedimentary basins of Northeastern Greece (basins of Strymon, Nestos
River Delta and Evros River Delta)
- Samothrace island
- Lesvos island
- Southern part of Chios island
- Aedipsos area (Northern part of Evia island)
Exploitation of geothermal energy in Greece
2-MWe pilot power plant on Milos island
9 In spite of the enormous geothermal potential
of the country, the degree of exploitation is
rather limited.
9 At present no electric power is produced from
geothermal resources in Greece, despite the
large high-enthalpy resources in the active
Aegean volcanic arc.
9 In 1985-86, a 2-MWe pilot power plant was
installed in the high enthalpy field of Milos
and operated intermittently until 1989 (the
total operating time was 9 months).
However, the plant was then shut down
because of environmental protests due to
H2S emissions into the atmosphere and
strong opposition from local inhabitants
and organizations (false information of the
local people have about environmental
impacts of electricity production from high
enthalpy resources & the actual
environmental problems related to H2S
emissions from the pilot power plant
during its operation).
Milos island: Reinjection pipeline
Geothermal well MZ-1 on Milos island
(Depth: 1,101 m,
T=310oC at 837 m depth)
The high enthalpy geothermal applications on the
islands of Milos and Nisyros have unfortunately
exhibited no progress mainly because of the negative
attitude of the inhabitants to geothermal exploitation.
They believe that such exploitation would unfavorably
affect the fragile ecological balance.
For this reason no further research in the high enthalpy
fields of these islands was carried out.
The ill-fated 2-MWe power plant on Milos Island is still in
the memories of the inhabitants of the island who are
rather strongly opposed to any new geothermal
development.
Fumaroles
on Milos island
Nisyros island
Geothermal applications in Greece (March 2011)
Summary of the various categories of direct uses
Use
Installed Capacity
(MWt) - 2011
Annual Energy Use
(TJ/yr)
Capacity Factor
Individual Space Heating
1.5
16.5
0.34
Greenhouse & Soil
Heating
35.0
340
0.31
Agricultural Products
Drying
0.3
1.5
0.19
Aquaculture *
9.5
74.3
0.26
Bathing and Swimming
(Balneology)
39.0
238.0
0.19
Subtotal
85.0
670.0
0.25
Geothermal Heat Pumps
90.0
460.0
0.16
TOTAL
175.0
1,130.0
0.21
* Fish farming & Spirulina cultivation
~ 135% increase since 2004
The growth rate of the installed thermal capacity for different
geothermal direct uses in Greece during 2000-2009
Capacity (MWth)
The growth rate of the installed capacity in Greece since 1994
)t
W
M
(
y
ti
c
a
p
a
C
200
180
160
140
120
100
80
60
40
20
0
1994
GHPs
Classical uses
1998
2002
2006
2010
Year

Estimated installed thermal capacity in March 2011: 175 MWt

Direct uses are rather stagnant over the past 10 years.

The significant increase is due to the rapid expansion of
Geothermal Heat Pumps systems
Geothermal Greenhouse Heating (I)
Today, there are ~21 ha of glass and plastic-covered
greenhouses. The area remains rather constant during the
past 15 years.
Most of the greenhouse area (~60%) is used for vegetable
cultivation. Main vegetables grown: tomatoes, sweet
peppers and cucumbers.
The rest: cut flowers (roses, lilies, chrysanthemum) and
potted plants
Sidirokastro (Macedonia, Northern Greece):
Geothermal greenhouse (plotted flowers)
Nigrita (Macedonia, Northern Greece):
Geothermal greenhouse (chrysanthemum)
Nigrita (Macedonia, Northern Greece): Geothermal
greenhouse (tomatoes)
Geothermal Greenhouse Heating (II)
Currently, there are 23 geothermal greenhouse
units run by 17 operators.
The vast majority (79%) of the geothermal waters
has a temperature less than 60ºC.
Greenhouse heating applications in Greece by geothermal field (2009-2010)
Geothermal greenhouse on Lesvos island
(Therma Geras)
Geothermal greenhouse on Milos island
(near the airport)
Geothermal Greenhouse Heating (III)
The following heating methods (or some
combination of these) are used in the
geothermal greenhouses:
Fan-coils heaters. Convective air heating
with forced-air heaters with water T >60ºC.
Cascade use of water with PP pipes.
Corrugated polypropylene (PP) pipes of
outside diameter (o.d.) 28 mm.
Large (d: 0.2 m) polyethylene (PE) tubes.
Finned metallic tubes. At the moment this
method is only applied to one floriculture
installation in Nigrita.
Distribution of the heating systems in
geothermal greenhouses (total covered area 21 ha)
PE tubes
Soil Warming
Soil warming for early-season asparagus
cultivation started in 1997.
Today ~ 19 ha, in Neo Erasmio and Myrodato
(Xanthi) and Nymphopetra (Thessaloniki) [inlet
water temperature 43-60oC]
The soil heating is
accomplished by
direct flow of the
geothermal water
through corrugated
PP pipes located 30-40
cm below the ground
level.
Neo Erasmio (Xanthi, Thrace): White asparagus
plantation under black plastic film covering
Cross-section of a
covered asparagus
bed
Schematic
diagram of the
soil heating
system
Neo Erasmio (Xanthi, Thrace): Green asparagus
plantation under transparent plastic film covering
Soil Warming – Protected vegetable cultivation
Soil warming (subsoil or surface heating) in combination
with an arch-type plastic cover of rows supported by
frames (low tunnel technology) can be also used for
protected vegetable cultivation aiming at intensive growth
and at shorter cultivation periods.
Intensive lettuce cultivation in Neo Erasmio (Xanthi, NE
Greece) during 2009-2010.
Heated cultivation area: 3 ha
Cultivation periods: November-December, March-April
During the last two winters > 2,000 kg of lettuce were
grown at reduced heating cost.
Arch-type plastic covered rows (low tunnels)
for intensive lettuce cultivation in N. Erasmio
Neo Erasmio: Subsoil heating in combination with low tunnel
technology for intensive lettuce cultivation
Neo Erasmio: Surface heating in combination with low
tunnel technology for intensive lettuce cultivation
Balneology
More than 700 thermal (or “curative”) springs
have been recorded in Greece.
About 60 spas and bathing centers, with a total
water flow rate of >1000 kg/s with water
temperatures in the range 18-90°C.
Attempts for upgrading with closed and open
pools (Aedipsos, Loutraki-Aridaia, Platystomo,
Sidirokastro, Loutraki-Corinth etc.)
Difficulties in documenting the energy use.
A conservative estimate (assuming that the
temperature of water leaving the bathing
facilities is 30oC) of the total thermal capacity
is 39 MWth with a mean load factor of 0.19.
Loutraki Aridea (Almopia, Macedonia): Open pool
Loutraki (Corinth, Peloponnese): Indoor pools (new modern spa)
Aedipsos [Northern Euboea (Evia)]:
Thermae Sylla Spa & Wellness Hotel
Dehydration of Tomatoes and other Agricultural Products
The tomato dehydration plant has been operating since 2001
in Neo Erasmio (Xanthi).
The unit uses low-salinity geothermal water (60°C) to heat air
to 58°C in a tunnel drier (air - geothermal water heat exchanger
system).
So far >100 t of high-quality dried tomatoes have been
produced.
It has been demonstrated that the unit is capable of drying
other vegetables and fruits.
Neo Erasmio - Xanthi: A tomato dehydration unit
Yearly production of dried tomatoes during 2001-2009
Individual Space Heating
Heating of a 1,300-m2 spa building in
Trainanoupoli (Thrace) using geothermal
water at 52°C. A titanium plate heat
exchanger is being used.
A 4,000-m2 spa building in Nea Apollonia
(Central Macedonia)
A hotel on Milos Island
Several individual houses in Macedonia
and Thrace.
Heating of several private houses on
Milos island is accomplished by a kind of
“downhole” heat exchanger.
Hotel on Milos island (there is a swimming pool
with geothermal water for relaxation)
Traianoupoli (Thrace, Northeastern Greece)
Nea Apollonia (Macedonia, Northern Greece)
Aquaculture – Anti-frost protection / heating
Anti-frost protection/heating of
aquaculture ponds in Porto
Lagos and Magana (both in the
Perfecture of Xanthi, Thrace) is
practiced since 1998 (installed
capacity ~ 8 MWt).
Anti-frost protection refers
mainly to the heating of
wintering ponds (earth
channels) with giltheads.
The injection of warm water into
the pond not only protects the
fish stock from bad weather,
especially during winter time,
but it has been shown that it
also increases fish production.

Porto Lagos (Xanthi): Anti-frost protection / heating of aquaculture ponds
(fish farming)
The use of geothermal energy in these fish farms proved indispensable during the
heavy frosts in the 2001-2002 and 2002-2003 winter periods and averted severe
damage (total loss) of the fish stock that has occurred in other farms of the region.
It is estimated that both investments were repaid during the first 3 years of operation.
Aquaculture – Spirulina Cultivation
Two Companies producing Spirulina have been
established in Therma - Nigrita (Serres,
Macedonia). The first unit was constructed in
1997 and the second one in 2009-2010.
The installations are located in greenhouses
covered with plastic foil.
The local geothermal water of 47-51oC can not be
used directly in the cultivation ponds because it
contains about 0.50 mg/l As. Fresh water heated
by the geothermal water is used.
The dissolved geothermal CO2 is also introduced
into the water.
The dried Spirulina product is available in form of
tablets, capsules and powders.
Therma - Nigrita (Macedonia, Northern
Greece): Production ponds for Spirulina
cultivation
Geothermal Heat Pumps (GHP) - I
During the past 4-5 years an impressive increase in
the number of systems installed in the country.
More than 500 applications have been recorded with a
total installed capacity of 60 MWt (The exact number
of GHP units installed in the country is not known, but
the above figure could well exceed estimated 90 MWt).
This rapid expansion of GHP systems (without any
State support) can be attributed to the following
factors:
(a) The easing of the licensing for drilling of “closed”
wells or for use groundwater in open systems
(b) The soaring oil (and gas) prices in 2008 and recently,
in connection to almost stable prices of electricity
(c) The increased interest of the air-conditioning sector
etc.

Horizontal ground-source heat collectors are installed
only for small buildings and are laid in a depth in the
range of 1.5-3 m.

The depth of the boreholes in the vertical GHP
systems ranges from 60 m to 100 m.
Angelochori (Thessaloniki):
Horizontal Geothermal Heat Pump System
(closed-loop system)
Skopelos island:
Horizontal ground-source heat collector
(closed-loop system) for a 80-m2 house
Geothermal Heat Pumps (GHP) - II
About 65% of the recorded installed capacity refers
to open-loop systems and ~25% closed vertical
systems.
In recent years there has been an increased interest
in seawater space cooling, especially for seaside
hotels, operating only during the summer.
The vast majority of GHP system has been installed
in buildings (private houses, large buildings etc)
Pylaia - Thessaloniki (Macedonia, Northern Greece) :
Engine room of the Town Hall with geothermal heat pumps
Eleones, Panorama - Thessaloniki (Macedonia,
Northern Greece) : Vertical closed-loop ground
heat exchanger installed in borehole
Pylaia - Thessaloniki
(Macedonia, Northern Greece) :
Drilling one of 21 vertical
boreholes, about 80m deep, for
the installation of a vertical
closed loop GHP system at the
Pylaia Town Hall
Geothermal Heat Pumps (GHP) for Agricultural Uses
A promising application
of GHP in Chrysoupolis
(Kavala): soil heating of
an area of 2.0 ha for
early-season asparagus
cultivation with an open
geothermal heat pump
system (groundwater)
The use of such a system
proved to be quite
economical, since the
Chrysoypolis (Macedonia, Northern Greece):
electricity bill accounted
GHP system for early-season asparagus
only for less than 15% of
cultivation
the producer’s price.
Kozani area
(Macedonia, Northern
Greece): Use of an
open-loop GHP
system (water - air)
for the heating of a
poultry farm
Kozani area (Macedonia, Northern Greece):
GHP system for heating a poultry farm
Geothermal
Legislation
in Greece (I)
Law 3175/2003 and Law 3734/2009 (article 37) and the relative Ministerial
Decisions:
The geothermal potential is a renewable energy source (RES), but exploration and
exploitation of geothermal energy is regulated by the “mining exploration decree”
(decree 210/1973).
“Field management” involves the coordination of the exploration efforts, the rational use
of geothermal fluids, the distribution and selling of heat to users etc.
Licenses for the management and exploitation of a field (or part of it, Law 3734/2009,
article 37) are provided by the Regions (for waters with T≤ 90°C), or directly from the
Ministry of Development for fields with higher fluid temperature (T>90oC).
Current feed-in tariffs for electricity production from geothermal energy (Law 3851/2010):
From low-enthalpy fluids (T≤90°C): 150 € per MWh
From high-enthalpy fluids (T>90°C): 99,45 € per MWh + 20% surcharge if the investment
is implemented without public subsidy
(discussions for 150 €/MWh)
Proven & Possible
Geothermal Fields
After the new national
g e o t h e r m a l leg is lation
(Law 3175/2003), I.G.M.E.
compiled a study and
classification of known
fields in the new
categories (high and low
temperature fields, proven
and possible fields).
At present, the known
proven and possible
geothermal fields exceed
40 in 30 different areas (in
some cases proven and
possible fields in the same
area) and they are located
all over the country. There
are two known high
temperature (T>90oC)
fields suitable for power
generation (Milos and
Nisyros islands). The
remaining fields are of low
t e m p e r a t u r e .
Proven and possible
geothermal fields in Greece
according to the Law
3175/2003 and Ministerial
Decisions
Geothermal
Legislation
in Greece (II)
Law 3498/2006 and the relative Ministerial Decisions concern:
Thermal springs and “development of therapeutic (curative) tourism”
Special Ministerial Decision (2004, update in 2009) defines the regulatory
framework for the licensing and the installation of Geothermal Heat Pump
Systems.
Recent news about geothermal exploration in Greece
During 2002-2008 new exploration activities were performed by I.G.M.E. in the
following areas:
- Lesvos and Chios islands
- Nea Apollonia, Almopia, Alexandria and Akropotamos (Macedonia, Northern Greece)
- Aedipsos - Yaltra - Lichada peninsula (Evia island, Central Greece)
- Sperchios graben (Central Greece)
- Sykies - Arta (Epirus, Western Greece)
- Riza - Antirrio (Western Greece)
A budget of 4 million € has been devoted to geothermal exploration.
An international open tender took place for the leasing of the right to explore the
geothermal potential of unexplored areas: (a) Central and Southern Chios, (b) Nestos
River Delta, (c) Evros River Delta and (d) Samothraki Island.
The deadline for the submission of the candidates’ bids was March 16th, 2011.
For the above-mentioned areas, the following Companies or Joint Ventures were
participated in this tender process: ENEL S.A., ORMAT Int., Hellenic Geothermal
Holding Corp. - of Canadian interests, PPC Renewables, Aegean Energy SA and ITA
Group SA - TERNA ENERGY SA. A total of 18 investment plans were submitted and
the value of submitted bids surpassed 350 million €. The duration of the bids
evaluation procedure may not exceed 50 days from the date on which the bids were
unsealed (i.e. March 16th, 2011).
Two open tenders took place for proven and probable low-enthalpy fields (proven
Eratino field & probable Lithotopos field).
Thank you very much
for your attention!