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

Country Update from Georgia
George Melikadze, Levan Tsertsvadze, Nodar Tsertsvadze, Otar Vardigoreli, Teimuraz Barabadze
Georgian Geothermal Association, Aleksidze Str. 1, 0193, Tbilisi/Georgia
melikadze@gmail.com

Keywords: energy, hydrodynamic digital model,
geothermal resources, Geothermal Circulation System.

development of the country based upon renewable,
ecological cleaner energy source.

ABSTRACT
Owing to its geological location, Georgia has considerable
resources of middle and low temperature thermal water (33ºC – 108ºC) that are presently for heat supply only. Most of
the geothermal wells are middle depth and non-operating.
On the other hand the economic development of the country
relies to a great extent on energy production. The
Geothermal potential of Georgia may be a promisingresource that could be available for energy production. Thisrequires an extensive study to re-assess the geothermal
potential of the country. Several projects were implemented
and some others are underway to achieve this purpose. This
paper summarizes the geothermal potential of Georgia
based on existing data and outlines one of the major
projects that has already been implemented to assess thepotential of Tbilisi geothermal field using thehydrodynamic digital modelling approach.

2. GEOLOGY
Geologically, the territory of the Republic of Georgia islocated in the Central and Western parts of the TransCaucasus and lies between the Euro-Asiatic and AfroArabian plates. This area marks the junction of theEuropean and Asiatic branches of the Mediterranean, also
known as the Alpine-Himalayan fold belt. The geologic
evolution of Georgia is controlled, to a great extent, by thedevelopment of the whole Caucasus segment of theMediterranean belt. The present structure of the ophiolithic
rock associations suggests that several oceanic basins weregenerated and developed during the period between thePrecambrian and early Mesozoic as a consequence of thehorizontal movements of the ancient East European andAfrican platforms, and some certain litho-stratigraphic
plates within the Mediterranean belt [2]. Apart from thePrecambrian and Paleozoic formations that cover a smallerarea, Mesozoic and Cenozoic rock assemblages mainly
make up the geological structure of Georgia. Three major
tectonic units can be distinguished according to thegeologic evolution of Georgia: 1) Fold system of theGreater Caucasus which represents a marginal sea in thegeological past, 2) Trans-Caucasus inter-mountain area
which marks the northern part of the Trans-Caucasus islandarc, 3) Fold system of the Lesser Caucasus, the southernpart of the ancient Trans-Caucasus island arc. Closely
related to the geological evolution, Georgia in which about
two thirds of the territory is occupied by mountains ischaracterized by rough topography. The country lies
between the Greater Caucasus in the north and the Lesser
Caucasus range in the south. The intermountain area that
extends between these two mountain ranges is divided by
the Likhi ridge into the Kolkheti (riv. Rioni) and Kartly(riv. Kura) lowlands. The Meskheti and Trialeti ridges
together with the volcanic highlands in the south make up
the major geographic units in Georgia.

1. INTRODUCTION
Taking into account the world-wide spread energy crisis,
the searching out and rational use of cheap and ecologicallypollution-free renewable energy sources is extremely
important. Among these sources deep earth heat is a noted
subject with great potential. The renewable sources that are
already in use in Georgia for power generation arehydropower plants and to a lesser extent wind plants. The
use of geothermal and biomass is limited to heat generation
while solar energy is not used at all. Georgia has a highpotential of geothermal sources, some of which have beenin use since ancient times. The major areas of utilization arebalneologic resorts, local heating systems, the processing
industry and greenhouses. Exploration and drilling researchcarried out in the 70s of the last century and sampled until
the present date reveal that Georgia abounds in geothermal
resources, concentrated in 44 deposits (Tabel. 9). According
to preliminary estimations, their heat power is 420
megawatts, and the exploitation of thermal energy ismaximum 2.7 million megawatt/hour/year. However, mostof the existing 50 geothermal wells in Georgia are ofmedium depth and supply water at temperatures ranging
between 40°C to 60°C. It also should be noted that most ofthese wells are non-operational. In spite of being concernedwith developing and opening up of natural resources,
Ministry of Environmental Protection and Natural
Resources has not issued many licenses until 2010. None ofthe wells are used for power generation. By estimation of
LTD “Geotherm” and “Georgian Geothermal Association”
the Georgian energy sector uses only 730,000 m3 perannum of the geothermal water, mainly to supply hot water
to the Saburtalo district of Tbilisi while other systems aredamaged or remain in the testing stage. Therefore, a reassessment of the geothermal potential of Georgia is ofmajor importance from the standpoint of economic

3. GEOTHERMAL RESOURCES AND POTENTIAL
Owing to the high geothermal potential in the South
Caucasus and particularly in Georgia, a confirmed totalreserves of 90,000 m3/day, corresponding to a heat potentialof 500,000 tonnes of equivalent fuel annually, has beenrecorded [3]. The amount of thermal flow for the main partsof Georgia can be listed as follows: 1) The south flank of
Caucasus Mountains - 100 mWm-2; 2) Plate of Georgia; a)
For the west zone 40 mWm-2 b) for the east zone 30mWm2; 3) Adjara-Trialeti folded system a) Central part 90 mWm2b) the east zone 50 mWm-2 ; 4) Artvin- Bolnisi platform
60 mWm–2. Figure 1 shows the main geothermal fields inwestern Georgia where the reservoir formations are
fractured karstic limestone’s of the Upper Cretaceous in thesedimentary trough and at the southeast where the reservoir
formations are volcanic and sandstones of PaleoceneMiddle Eocene in the fold system. Thus we see the1Melikadze et al.
following pattern in the distribution of heat flow: themaximum heat flow is observed for the central zone offolded part of Georgia and the minimum for the plate. As toheat flow for Adjara-Trialeti folded system, is characterized
by the middle range. The temperature condition of thePaleocene- middle Eocene thermal water bearing complex
is better investigated for Tbilisi region. This investigation
revealed that temperature condition of this complex isinfluenced by the depth of the layer of high thermal
resistivity upper Eocene rocks as well as their thickness.
From the surface of Volcanic-sediment formation of middle
Eocene the temperature of rocks increases in all directions
from 200C till 1000C. To the north-east the increase oftemperature is less than in other directions because of theproximity of the plate. At the contact of Cretaceous –Eocene temperature has remarkable variation: to thefarthest west, where upper Cretaceous is raised up to 500m
we have temperature variation from 1000C - 1600C, when tothe North and East, where the Cretaceous sinks to 600m wehave temperature about 2400C.

Saburtalo section which is related to the same Middle
Eocene thermal water horizon.
Currently the water low in minerals tapped in the central
area is used by the Tbilisi Balneological Health Resort andthe hygienic bath houses (450C - 500C). The hightemperature water (570C - 740C) tapped in the Lisi (wells№ 5-t, 7-t, 8-t) and the Saburtalo (№ 1, 4-t, 6-t) areas withtotal discharge of 4000 m3/day is used for hot-water supply
and heating the population and offices. Furthermore, there
is farming and other complex under construction at Lisi
Lake. Negotiations are conducted with LLC “Lisi Lake” forsupply of large healing-recreational and residential complexaround the lake, with complete geothermal heating. It isworth noting that the thermal waters in the three areas areof the same composition. They are of low T.D.S. content(0,19-0,26 g/L), with alkaline reaction. It is of sulphatechloride-sodic type with the content of hydrogen sulphide.
The 25-year exploitation of the Lisi area showed thatutilization of thermal waters under such a regime (wellconsumer-sewage) causes a gradual reduction of water
discharge in production wells as the amount of theproduced water exceeds the rate of natural recharge of theunderground reservoir.
This may result in stopping water flow in the well. To
prevent this, it is necessary to install a Geothermal
Circulation Systems (GCS) in the Lisi area. Favourable
conditions exist to do this in this area. In particular, there
are production wells № 5-t, 7-t and 8-t and № 1-Lisi and 9-t
wells (with depth 2556-3702 m) with the negative levelsuitable for reinjection. The above mentioned wells haveintersected the Middle Eocene thermal confined aquifer,thus the reinjected water will circulate only in this aquifer.
Consequently, the World Bank (WEF) and UNDP financed
aquifer-testing and have created hydro geological model ofa GCS system for the Lisi area. As a result of implementing
such technology, it will be possible to gradually transfer thewhole capital to the geothermal heat supply. In addition to
the large economic profit, it will have a significant
ecological effect, for the population in the Saburtalo region(120,000) will substitute by geothermal energy instead ofusing 30.6 thousand tons of equivalent fuel (EF).

Figure 1. Main geothermal fields in Georgia.
Complete development of this energy will make it possible
to save up to 500,000 tonnes of conventional fuel (TCF) per
year and reduce the CO2 emission level in the atmosphereby 1.22 million tonnes.
Today the amount of confirmed reserves does notcorrespond to reality because, under the current conditionsof exploitation, well pressure and discharge rates aredropping. This will make it necessary for us to examine thecurrent situation at the existing thermal water deposits andto re-assess their reserves.

Second, is the Zugdidi-Tsaishi region. In 1992, 24 wells
were drilled. From depths of 1272-2820 m water with3
temperature 830C - 980C Q=25,000 m /day was found;enough to offset 42,5 thousand tonnes of equivalent fuelEF (the annual production 250,000 megawatt/hour).

4. GEOTHERMAL UTILIZATIONAs it is evident from the tables, only small parts ofresources are used, even when it could remarkably improvethe economic condition of country.

On the request of Georgian Government a Icelandconsulting group “Virkir-Orkint” evaluated Geothermal
Resources of this region. On this basis the Americancompany “Berns and Ro-ue” together with Georgianscientists did hydrogeologic – geothermic testing. Now it istime to plan a new modern enterprise using uniqueconditions- existence of the deep holes with hightemperature steam-water mixture. The position of theseboreholes make it possible to construct three independent
GCS.

Among thermal water deposits available on the territory ofGeorgia two main thermal aquifers – Tbilisi and ZugdidiTsaishi, are distinguished by their wide regional expansion,considerable thickness, high collecting and filtration
properties, water abundance and high water temperature. Itis exactly these two thermal aquifers which can partiallysolve the existing energy problem in Georgia. Urban centre
Tbilisi is of a particular importance with its multilateral anddimensioned consumer existence, thermal water resources,
unlimited perspective of development and population of 1.5
million. As a result of historical and research work andchronology the Tbilisi thermal waters deposit haveconditionally been divided into 3 exploitation sections:central or balneology resort and baths section, Lisi and5. DISCUSSION
Launching the rational regime of deposits exploitation
recommended in this proposal may considerably increase
these parameters. If we take into account that Georgia has
no domestic fuel resources of its own and after the politicalcollisions of the 90s, the country’s heat supply system has
been completely destroyed, it will be clear how important it
is to develop local renewable resources. To connect the2Melikadze et al.
cheap and ecologically clean geothermal energy to thecountry’s common heat and cold supply system, it isnecessary to calculate geothermal resources, the thickness
and the potentialities of individual deposits, to introduce
current progressive technologies, and to chart rational
schemes.

A Correia, J. Carneiro, G. Buntebarth, T Chelidze, G.
Melikadze, “Numerical simulation of groundwaterflow and heat transport in the Tbilisi hydrothermalreservoir”, M. Nodia Institute of Geophysics, Georgian
AcademyofSciences,Europian.Center,"Geodynamical hazards of Highdams" Open Partial
Agreement on Major Disasters, Council of Europe,. G.
Buntebarth, T. Chelidze Tbilisi 2005.

REFERENCESSEEC (South East Europe Consultants) 2007. Georgia:
Strategic Environmental Assessment of Power Sector
Development, Final Report.

Melikadze, I. Kobzeb, N. Kapanadze, Z. Machaidze, Th.
Jimsheladze, Analyze of underground water regime
factors for determine tectonic component, LEPT
Institute of Hydrogeology and Engineering Geology,
Collection articles, vol. XYI. Proceeding ofConference Dedicate to the 100-th Anniversary ofProfessor Josef Buachidze. Tbilisi. 2007.

Moores, E. M., Fairbridge, R.W., 1997. Encyclopedia ofEuropean and Asian Regional Geology, Springer Publ.
p 804.
Lund J W., and Freeston D H., 2001 World-wide direct usesof geothermal energy 2000 Geothermics Volume 30,Issue 1, 29-68.

JimsheladzeT,
Kapanadze
N,MelikadzeG.
“Microtemperature observation in Tbilisi seismoactivregion”, Journal of Georgian Geophysical Association,№12, 2008.

G. Buntebarth, T. Chelidze, G. Melikadze-Hydrodynamic
and microtemperature monitoring in seismic areas.
Georgian Engineering News, # 3, 12-132, 2004.

Tamaz L. Chelidze, Tamar J. Jimsheladze, George I.
Melikadze , "Induced seismicity due to the oil
production in Tbilisi region, Georgia”, Journal ofGeorgian Geophysical Association, №12, 2008.

G. Buntebarth, T Chelidze, G. Melikadze, Hydrodynamic
and microtemperatur monitoring in seismic areas:Tbilisi hydrothermal field, Georgia, Caucasus. “Timedependant microtemperature and hydraulic signals
associated with tectonic / seismic activity”, M. Nodia
Institute of Geophysics, Georgian Academy ofSciences, Europian.Center, "Geodynamical hazards ofHighdams" Open Partial Agreement on Major
Disasters, Council of Europe,. G. Buntebarth, T.
Chelidze Tbilisi 2005.

N.Tsertsvadze, O.Vardigoreli, B.Vashakidze, V.Barnov,
N.Kotrikadze - Generalization of the Projects ofProduction Testing Exploitation of Georgian Thermal
Waters for Working out a Scheme of Their Rational
Utilization. – Tbilisi, 1990. The "Sakburggeothermy"
Funds. (In Russian).

3

Melikadze et al.
Table 1. Present and planned production of electricity.
Geothermal
Capaci
ty
MWe

Gross
Prod.
GWh/yrIn
operationin
December
2009

Fossil fuelHydro

Capaci
ty
MWe

Gross
Prod.
GWh/yrCapacity
MWe

Gross
Prod.
GWh/yr

1718

1698

2473

6163

Under
constractionin
December
2009

NuclearCapacit
y MWe

Gross
Prod.
GWh/yrOther renewable(specify)
Capacit
y MWe

Gross
Prod.
GWh/yr1052878088

5102810

2300

Funds
commited,
but not yet
underconstructio
ninDecember
20091

Total
projecteduseby2015

Total
Capacity
MWe

Gross
Prod.
GWh/yr

6000

1900

700

8600

10000

8000

1500

25000

Table 3. Utilization of geothermal energy for direct heat as of 31 December 2009 (other than heat pumps).
Maximum Utilization
LocalityType 1)

FlowRate(kg/s)

Annual utilization

Temperature (0 C)

Enthalpy2) (kJ/kg)

Inlet

Outlet

Inlet

Capacity3)(MWt)OutletAve.
Flow(kg/s)

Energy4)

Capacity(TJ/yr)

Factor5)

Tbilisi

B,G,H, D

46.4

65108.7440.4

239.790.87

Zugdidi

G,H

77.22

87

4513.5765360.090.84

AgaraG

10.581312.20

959.360.86

659.24

0.86

TOTAL

134.1224.51

I = Industrial process heat

H = Individual space heating (other than heat pumps)

C = Air conditioning (cooling)

D = District heating (other than heat pumps)

A = Agricultural drying (grain, fruit, vegetables) B = Bathing and swimming (including balneology)
F = Fish farming

G = Greenhouse and soil heating

K = Animal farming

O = Other (please specify by footnote)

S = Snow melting
Note: please report all numbers to three significant figures4Melikadze et al.
Table 5. Summary table of geothermal direct heat uses as of 31 December 2009.
Note: please report all numbers to three significant figures.
Installed Capacity1)

Annual Energy Use2)

UseCapacity Factor3)

12(MWt)(TJ/yr = 10 J/yr)

Individual Space Heating4)

13.57

360.090.84

District Heating 4)

8.74

239.79

0.87

2.20

59.36

0.86

24.51

659.24

0.86

Air Conditioning (Cooling)
Greenhouse Heating
Fish Farming
Animal Farming
Agricultural Drying5)
Industrial Process Heat6)
Snow Melting
Bathing and Swimming7)
Other Uses (specify)
SubtotalGeothermal Heat Pumps
TOTAL

Table 7. Allocation of Professional personel to geothermal
Activities: (Restricted to personnel with University degrees)(1) Government(4) Paid Foreign Consultants(2) Public Utilities (5) Contributed Through Foreign Aid Programs(3) Universities(6) Private Industry
Professional Person-Years of EffortYear
(1)

(2)

(3)

(4)

(5)

2005

2211222006

2211222007

32

123

314

2008

321244142009

4215

4415Total

1410611515435(6)Melikadze et al.
Table 8. Total investments in geothermal in 2009 (US$).
Research andDevelopment
incl. Surface
Explor. And
Exploration
Drilling

PeriodMillion US$

Field
Development
Including
Production
Drilling &Surface
Equipment

Utilization

Funding Type

DirectElectricalPrivate

PublicMillion US$

Million US$%%

Million US$

1995-1999
2000-2004

0.17

2005-2009

0.35

0.17

100100

Table 9. Parameters of main geothermal deposit of Georgia.
Deposit’s
name

Quantity ofbore holes

Temperature

Flow rate

t °C

m3/dR

Thermalcapacity (MWt)∆t=t-25°C

Conventional fuel(TCF) Thousand
tonne per year

1Gagra338-43920

0,81,142

Besleti239-41370

0,250,343Dranda

193

1500

4,8

7,0

4

Kindgi1175-108

26600

95

141,25Moqva

8100-105

13470

48,973,5

6Oxurei

2104

3500

12,8

19,1

7

Tkvarcheli

235-38

690

0,35

0,53

8Rechkhi

1771080

2,6

4,5

9

Saberio134

1230

0,50,810

Zugdidi-Tcaishi

1578-98

24564

69,8

103,8

11

Torsa

163

108

0,20,3

12

Oqros satsmisi

163

104

0,20,3

13

Qvaloni

264

4300

11,6

17,2

14

Khobi

178-98450

1,11,715Bia

182

2600

4,87,216

Gafshakari

165

120

0,20,317Zeni

164372

0,91,418

Zana

180

400

1,42,119Mengi

31015750

9,2

13,620Isula

157-65

370

0,9

1,321

Noqalaqevi

275

700

1,82,622

Tskaltubo

75 + 4 sp.

80-82

20000

7,7

11,5

6

Melikadze et al.
Deposit’s
name

Quantity ofbore holes

Temperature

Flow rate

t °C

m3/dR

Thermalcapacity (MWt)∆t=t-25°C

Conventional fuel(TCF) Thousand
tonne per year

23

Samtredia

161

3000

4,9

7,224

Vanis raioni352-602152

3,24,825

Vani260

2780

4,56,826Amagleba

141346

0,30,527

SimoneTi

1425200,40,628

Abastumani

3 sp.

48

1040

1,1

1,729

Vardzia

345-58

1330

1,75

2,730

Tmogvi

162

520

0,91,331

Naqalaqevi334-58

795

0,64

1,05

32

Aspindza

142864

0,71,033

Tsixisjvari

132

1000

0,34

0,534

Borjomi

2530-41537

0,40,635

Axaldaba

433-42

500

0,26

0,43

36

Tsromi539-55

732

1,03

1,64

37

Agara

182

260

0,71,138

Khvedureti

245-49140

0,150,239

Tbilisi I

756-703760

6,59,940

Tbilisi II

538-48

1111

0,82

1,16

41

Ujarma

14250

0,04

0,06

42

Torgvas-abano

1 sp.

35

800

0,40,643

Tsnori137

864

0,50,75

44

Heretiskari234-373300

1,65

2,6135599

307,1

458,4

206 bor.
Sum8 spring

7