Session 1 GEOTHERMALL ELECTRICITY PRODUCTION: POSSIBILITIES, TECHNICAL AND ECONOMIC FEASIBILITY IN CENTRAL EUROPEAN REGION Tevfik Kaya: KIZILDERE – NEW GEOTHERMAL POWER PLANT IN

I.2.

KIZILDERE – NEW GEOTHERMAL POWER PLANT IN TURKEY 1. Stage 60 MWe Turkey’s Biggest Geothermal Electricity Plant Development Project Privatization of Kızıldere Geothermal Power Plant and Current Approaches for the Field & Plant

Tevfik Kaya, Ali Kindap Zorlu Energy

ABSTRACT Kızıldere Geothermal Field is discovered in 1960s by General Directorate of Mineral Research and Exploration (MTA). After 24 years of operation by EÜA , state-owned electricity production company, the government decided to privatize Kızıldere Geothermal Plant, and privatization took place on March 5, 2008. As a result of this privatization, the licenses and rights of this Field is transferred to Zorlu Energy Group on September 1, 2008, who won the tender. From that day forward, an intensive work towards developing the Field has commenced: Starting with a due diligence study followed by the gathering and evaluation of all data in hand, the Group plans to develop the geothermal field so as to meet both short term (15MWe energy production) and long term (60 MWe energy production) production targets. In this regard, while on one hand, a feasibility study is being prepared by a foreign consultant company, on the other hand, geophysical-geochemical studies, mechanical cleaning work, inhibitor tests and preparation of re-injection wells are continuing.

1. Introduction through a privatization tender. Receiving all legal rights for the exploitation of this resource, Kızıldere Geothermal Field, located in south Zorlu Energy commenced working on this new east of of Western Anatolia, in project with the ultimate aim of constructing a the province of , Turkey, (Figure 1) was new, sustainable power plant with 60 MWe discovered by General Directorate of Mineral capacity as the first stage of power expansion. Research and Exploration (MTA) in 1965. As a first step in the project, the operating Following this discovery, various scientific efficiency of the current power plant has been studies have been conducted at the site with the increased from 6 MW to 15 MW. ultimate aim of converting this geothermal Meanwhile, a new exploration programme is resource into electricity. For this purpose, the prepared, and geochemical and geophysical first pilot power plant with 500 kWe capacity (gravity and magnetic surveys, resistivity was constructed in 1974, followed by a 17.4 surveys) studies commenced in line with this MWe capacity power plant commissioned by programme. After the completion of required TEK (Turkish Electricity Authority) in 1984. exploration and environmental studies, new On September 1, 2008, Zorlu Group, one of wells are going to be drilled within the scope of the biggest holdings of Turkey, has acquired 2 this plan to produce electricity at the planned exploitation license for 70 km Kızıldere new power plant. In this regard, resource Geothermal field and current Power Plant modeling studies still continue, along with the

1 Proceedings of the International Conference on NATIONAL DEVELOPMENT OF GEOTHERMAL ENERGY USE and International Course/EGEC Busiess Seminar on ORGANIZATION OF SUCCESSFUL DEVELEOPMENT OF A GEOTHERMAL PROJECT, K. Popovski, A.Vranovska, S. Popovska Vasilevska, Editors feasibility studies, and environmental impact thermal Energy projects into its program and assessments to get necessary legal permits. started to play a key role in exploration, pro- The Investor of this project, Zorlu Holding, duction, well maintenance and operation servi- has been active in energy sector since 1993 and ces of the geothermal field. Company works has achieved a continuous growth in the sector with highly skilled human resources profile, with its Energy Group Companies. The compa- and, professionals working in geothermal pro- ny engages in the various activities in the en- jects have long experience in geothermal re- ergy sector including hydrocarbon exploration, source development. The company also gets ad- production, distribution and trading, renewable ditional consultant services from reputable energy development and power plant opera- foreign consultant firms and academia when tions. In 2008, with the transfer of rights of deemed necessary. Kızıldere Field, Zorlu Energy involved Geo-

Fig. 1. Map of Turkey and Kızıldere Geothermal Field

Turkey is a net energy importing country efficient way. Turkey has ambitious targets in and her energy policies are being constructed so the development of renewable resources: By as to achieve diversification of energy mix in 2020, 25% of the electricity demand is expected the most environment friendly and energy to be met by renewable energy resources and

2 Session 1 GEOTHERMALL ELECTRICITY PRODUCTION: POSSIBILITIES, TECHNICAL AND ECONOMIC FEASIBILITY IN CENTRAL EUROPEAN REGION Tevfik Kaya: KIZILDERE – NEW GEOTHERMAL POWER PLANT IN TURKEY total installed geothermal power capacity is develop the field to achieve increased planned to be 600 MWe. Zorlu Energy is aware production targets. of these targets set forth for the next decade, and working to meet increasing energy demand 1. History of Geothermal Energy in in the most sustainable way, the Group invests Kızıldere Field in renewable energy projects some of which Kızıldere is the first geothermal field used for include hydroelectric power plants (190 MWe), electricity production in Türkiye. The geo- geothermal plants, solar systems (120 KWe) thermal field is named after Kızıldere city, and wind farms (225 MWe). Kızıldere geo- which is located in the south east of Aegean thermal field is the largest and most important Region of Western Anatolia. The license area geothermal field in Turkey, and Zorlu Energy is covers partly Sarayköy and towns of working hard to develop this resource to Denizli and Buharkent town of Aydın (Figure achieve clean and sustainable electricity pro- 1). duction. Despite promising geological studies The initial exploration studies in the field go and reservoir estimations, the Field has been back to 1960s: In 1965, following geological operated with low capacities and production and geophysical studies; MTA performed the rates over the last 25 years. Hence the develop- first well drilling in the area to the depth of 540 ment of the project will provide a source of meters, and observed 198°C of temperature in clean, reliable, economical, indigenous electric the well. Between 1965 and 1973, 16 more power and will reduce the country’s reliance on wells have been drilled in the field whose foreign oil and gas for power generation. The depths are varying from 370 to 1241 meters. In project will be a state-of-the-art geothermal 1974 a 0,5 MWe pilot turbine is constructed by facility, based on technologies developed MTA and this turbine is mounted to KD-13. around the world to make geothermal plants With this pilot turbine, three nearby villages’ very efficient and reliable sources of electric electricity demand is supplied free of charge power. Hence, this project is an innovator for between 1974 and 1980. Following this pilot new projects concerning the use of geothermal study, in 1984, the first geothermal plant which resources and the success of this project should has a generator output of 15 MWe and a total reduce the perceived risk of development el- capacity of 17, 4 MWe is constructed. Between sewhere in Turkey. Believing that sustainability 1985-1986, 3 new wells (KD-20, KD-21, and is the key element in energy projects, Zorlu KD-22) were drilled to supply the plant with Energy is aware of the potential Kızıldere vapour, increasing the total number of wells in Geothermal Field carries and is dedicated to the field to 9.

Fig.2 Production in Kızıldere Geothermal Power Plant

3 Proceedings of the International Conference on NATIONAL DEVELOPMENT OF GEOTHERMAL ENERGY USE and International Course/EGEC Busiess Seminar on ORGANIZATION OF SUCCESSFUL DEVELEOPMENT OF A GEOTHERMAL PROJECT, K. Popovski, A.Vranovska, S. Popovska Vasilevska, Editors

At first, R-1 was planned to be a reinjection Lycian nappes. The Menderes massif, with its well and drilled at a depth of 2261 m. in 2001. dome-like rise, has gained the feature of a However it is discovered to have the highest tectonic window and as a result of the temperature (242 °C) geothermal well in the extension, the graben systems have developed. field, as well as in Turkey, and because of its Another important factor that caused the productivity and high enthalpy; it is now being development of the graben systems is the used as a production well. R-2 is drilled to be collision of the Anatolian- Arabic plates along used as a reinjection well in 2002 at a depth of Bitlis suture zone so the Anatolian plates move 1428 m. This well is the only reinjection well of towards west with North and East Anatolian the field. faults starting from Tortonian. Three reservoirs have been identified in the In the Plio-Quaternary, regional tectonic Kızıldere region: First reservoir is Sazak For- factors initiated the formation of grabens and mation between Pliocene units. Second reser- the effects of these factors can still be observed voir is Igdecik Formation of Menderes Meta- today. The known and registered earthquakes morphics and third reservoir is gneiss and also confirm this fact. The faults generating the quartzite under the micaschists. Pliocene aged grabens and horsts are generally parallel to each clay, marl and sandstone alterations represent other and normal slipped. Also reverse faults’ the caprock in the geothermal system. Besides developments are conformable to graben these discovered reservoirs, recent research tectonics. studies indicate the possibility of a fourth and Tectonic: The term of neo-tectonic means all undiscovered reservoir with a temperature the tectonism within a time from last tectonic varying between 250-260°C. To prove the change in regime in any region until today existence of this new reservoir, a new explo- (Sengör, 1980). According to the definition, the ration well is planned to be drilled to a depth of neo-tectonic age in Turkey started with the 3000 m in the greenfield area. The reason of collision of Anatolian and Arabic plates on such a deep target depth is that the hotter Bitlis suture zone As a result, the Anatolia plate reservoir will probably be under the depth of including Central and West Anatolia started to 2500 meters. be pushed over Eastern Mediterranean litho- sphere which can easily slip towards west from 2. Geology of Kızıldere Field East Anatolia pressure region along with North The geological evolution of the region is and East Anatolia transform faults. Since the explained by the principles of the “Plate direction of North Anatolia transform fault tectonics” and it was concluded that Western changes into SW-NE direction, Hellenic shear Anatolia is important in terms of the fields zone at the west of the Saros Bay prevents the where the greater slip-step fault zones and Anatolian plate from moving towards west and faults with different directions intersect or there is a pressure regime towards the east- converge during the development of the west direction in all Aegean and West Anatolia. geothermal graben in the region . At the same time, since the Eastern Medi- As the stratigraphic units of the region, Pa- terranean lithosphere (Levant oceanic crust) leozoic Menderes metamorphic basement takes dive under the Anatolian plate, an anatexis zone place. The metamorphic mainly consists of was formed under the Menderes massif so the gneiss, variety of schists, quartzite, micaschists intrusions of the massif developed and the and marbles. Cenozoic terrestrial-lacustrine massif uplift (Sengör & Yılmaz, 1981). sediments are overlying these metamorphic Therefore, all these effects created the rocks. Aegean graben system. Menderes Massif is at At the Middle Miocene, the subduction zone the centre of the Aegean graben. Kızıldere developed from Taurus Mountains towards geothermal field is at the intersection point of lower part of the Anatolides caused partial the Büyük Menderes and Gediz grabens in melting and igneous intrusions in the massif. Menderes Massif The dense ophiolite covered the massif The edge faults of all grabens in the Aegean transported southwards and generated the graben system, have a decreasing slope towards 4 Session 1 GEOTHERMALL ELECTRICITY PRODUCTION: POSSIBILITIES, TECHNICAL AND ECONOMIC FEASIBILITY IN CENTRAL EUROPEAN REGION Tevfik Kaya: KIZILDERE – NEW GEOTHERMAL POWER PLANT IN TURKEY deeper in accordance with listrique normal Geothermometry faults. (Na-K-Ca and SiO2) show that the temperature After Gökdere fault, that is the main fault of of the reservoir is between 240 and 260oC in the Büyük Menderes graben at the north, the Kızıldere field. parallel folds are detected in Kızıldere Geothermal Area. The fold especially in front Isotope Analyses of the Kızıldere fault is covering faults of The isotopic compositions of water samples whose wave length decreased towards deeper. are taken from R-1 in the Deep Reservoir and Similar folds can be seen in the graben tectonic from several wells (KD-6, KD-13, KD-15, KD- locally (Goguel, 1952). The directions of the 21) in the second reservoir (Simsek et.al. 2000). folds are almost E-W direction. The wave Stable isotope analyses of water samples lengths decrease towards southward within 2 indicate that the geothermal waters have a km. after Kızıldere fault. These folds are clearly meteoric origin. There is a clear d18O shift seen in Gebeler stream valley where Kızıldere from the MMWL and cold water values. This hot springs take place and natural profiles in the suggests that, water-rock interaction is an valleys which are parallel to that valley. The important process for geothermal fluids and fractures and faults occurred where the folds implies deep circulation and high temperatures. are overpressured (Şimşek et al., 2009). Hot spring waters and deep geothermal well (Simsek et.al. 2000 and Simsek 2003). Hydro-Geochemical Studies In Kızıldere Region: There are a few surface waters, cold Gas Measurement in the Wells springs and mineral water and thermal springs The non-condensable gas content of all wells and fumaroles at the vicinity of the Kızıldere except R-1 are approximately %1-1.8 by area weight. For R-1, this value is %3 by weight. Since 1968, 25 deep wellbores are drilled in Geophysical Studies In The Kızıldere Re- Kızıldere geothermal area and its vicinity. gion: First geophysical studies around Denizli Today, 24 of these wellbores remain within province was carried out by MTA: In 1965, a Zorlu Energy license area. These wells, whose gravity survey in an area of 1500 km² and an depths change from 370 meter to 2261 meter, electrical resistivity survey around Kızıldere- have fluid temperatures varying between 137 Tekkehamam field covering 40 km2 area were °C to 242 °C. conducted (Tezcan, 1967). Following these Geochemical analyses of cold, hot springs studies, gradient wells approximately at 130 and wells in the Kızıldere area and its sur- locations were drilled in Kızıldere, Tekkeha- roundings show that three types of water exist mam and Karakova fields (Demirörer, 1967) in the region. (I) Alkaline bicarbonate waters and detailed 1/10000 scaled gravity surveys (4500 ppm

5 Proceedings of the International Conference on NATIONAL DEVELOPMENT OF GEOTHERMAL ENERGY USE and International Course/EGEC Busiess Seminar on ORGANIZATION OF SUCCESSFUL DEVELEOPMENT OF A GEOTHERMAL PROJECT, K. Popovski, A.Vranovska, S. Popovska Vasilevska, Editors mam fields, during ENEL-TEK joint site conductive area. Thickness of the conductive feasibility project. These anomalies overlapped zone was determined as 9 kilometers. This area in a geological map. can be interpreted as magma rising and getting With the acquisition of the license area, close to the surface. Also, within the scope of Zorlu Energy has hired MTA as a sub-cont- this study, a total of 4 seismic lines were re- ractor to perform gravity, resistivity and verti- corded for a total length of 25 km. The results cal electrical drilling studies in the Kızıldere were then evaluated and mapped together with license area. Details of these studies are electromagnetic and resistivity studies. presented in Project Activities. Geothermal anomaly map is prepared by Gravity data provide information about utilizing data obtained from geology and geo- general situation, direction and size of graben physics (MT and seismic studies). Main re- and horsts. The results of resistivity studies charge area of the field is horsts where per- justify the geologic data and allow for the meable formations are found. The limestones of identification of some zones with low resistivity Sazak formation and wide alluvial basin are as well as the determination of the thickness of also important recharge areas. Recharge of all Neogene cap units. New well locations in geothermal reservoirs depends on surface Kızıldere geothermal field will be decided recharge and also intensive fracture systems. based on this information. Totally 130 gradient wells were drilled in the Heat sources: Meteoric water is heated in deep caprock with depth range between 80-150 m to sections by magmatic emanations. Develop- obtain more reliable results about Kızıldere ments of geothermal possibilities were obser- geothermal area (and its vicinity) anomalies. ved as a result of mainly big slip and inter- 100 of these wells were drilled in Kızıldere secting deep faults formed by intense tecto- whereas the reaming 30 wells were drilled in nism. Also, high rate of extension of grabens Tekkehamam area (Demirörer, 1967, Şimşek, are important especially for recharging the area 1977). Isothermal lines were drawn for 100 m and for the circulation of geothermal fluids. depths of gradient wells in Kızıldere and 3. Exploration Activities in Kızıldere Field Tekkehamam areas. Anomalies which were Kızıldere first stage 60MWe Geothermal determined according these values are Power Plant Reservoir Assessment and overlapped to isogradient lines. These anomaly Feasibility Studies still continue. Preliminary values corresponding to 92 °C per 100 m in assessments regarding the project indicate that Kızıldere and up to 110 °C in Tekkehamam the project the power plant will utilize double area. The lowest value was determined about 30 flash system. Zorlu Energy is working with °C. Gradient value was taken as ground tem- foreign engineering and consultancy compa- perature per 10 m increment. This value was nies, namely, Power Engineers (PEI), Geo- determined in a range between 1 °C/10 m and logica, APEX and Veizades and Associates, for 10 °C/10 m. the successful achievement of the project. Isogradient map constructed by gradient well However, it is not possible to comment on the data’s of Kızıldere geothermal area shows an type and engineering specifications of the anomaly on W-E direction, from Kızıldere planned plant before the completion of the town toward to Tosunlar town. All of these feasibility studies. anomalies are conformable with geological and For the 1st Stage 60MWe power plant to other geophysical data. Deep wells were drilled work efficiently (as a first stage), 25 produc- at central part of this anomaly. While tion/re-injection wells are required. Therefore, geothermal gradient of the anomaly observed in if existing wells are to be used, 15 additional the geothermal wells located in middle of the wells will be needed. In this regard, 10 field is 7.0 °C/10m, it is seen that these values wellhead equipment are ordered for the drilling fall down to 3° C/10 m at the deep wells located of the new wells. The drilling activities at the at the south of the field. site will commence on August 2009, depending In 1988, ENEL conducted an electromag- on the delivery of the equipment to the site. netic survey at 25 points to define the 6 Session 1 GEOTHERMALL ELECTRICITY PRODUCTION: POSSIBILITIES, TECHNICAL AND ECONOMIC FEASIBILITY IN CENTRAL EUROPEAN REGION Tevfik Kaya: KIZILDERE – NEW GEOTHERMAL POWER PLANT IN TURKEY

The planned and ongoing exploration and Reservoir Capacity Estimation and Feasi- reservoir assessment activities in order to feed bility Study: Reservoir modeling studies have the first stage 60 MWe plant can be sum- been started on February 2009, and are ex- marized as follows: pected to be completed by June 2009. The stu- Geological investigation at the Site: Geolo- dies are being conducted by an international gical studies at the site started with gathering team of experts including academicians from and filtering of all the available information up METU and Hacettepe Universities, PEI, Geolo- to date to assess current situation of the site. gica, Veizades and Associates, and experts This study, conducted by academicians from from Zorlu Energy. Middle East Technical University (METU) and Hacettepe University, was not only helpful in Permit Applications: Various legal permits are terms of providing a better understanding of the required for operating the power plant. These site geology and reservoir, but also allowed for permits include; Exploitation License for Geo- defining a roadmap for the rehabilitation of thermal Field, Electricity Generation License existing production and re-injection wells, as from EMRA, Environmental Impact Assess- well as identification of further exploration ment (depending on the legal status of the site). activities. Within the scope of this roadmap: Exploitation license of the 70 km2 field has Geochemical exploration studies have star- been acquired on 2008 for a period of 30 years. ted in March 2009, and still continue. These Other permit applications are still ongoing as studies are aimed at determining the geoche- the project progresses. mical properties of the reservoir fluid, and Detailed Engineering: After the completion of foreign consultants from reputable institutions the feasibility studies, detailed engineering such as Institute of Geosciences and Earth Re- design of the first stage 60 MWe power plant sources (CNR) and US based Power Engineers will be done. (PEI) are being involved in the testing process as well as the interpretation of the results. Power plant construction: After obtaining Geophysical exploration including gravity- relevant permits, construction phase of the new magnetic surveys and resistivity studies, on the power plant will commence. Total duration of other hand, started on March 2009. Gravity and the construction period is anticipated as 40 magnetic surveys, conducted by MTA, are months. completed with the analysis of a total number According to existing data and reports, and of 888 point surveys. The results of this survey preliminary results of the Feasibility Study con- are being evaluated by the experts and the ducted by PEI, the resource capacity has a 90% evaluation studies will be completed in May probability of producing 65MW electricity, 2009. Resistivity and DES studies, again being 50% probability of 122MW and 10% pro- performed by MTA, have started in April 2009, bability of 203MW over 30 year life. Currently, are expected to be completed in 1.5 months. the generated electricity is being transmitted via All exploration activities conducted so far , Sarayköy and Simav transmission lines are towards identifying successful new well according to the agreement that exists between locations which will allow for the most bene- ADÜAŞ (former operator of the existing power ficial exploitation of the third reservoir with a plant) and Turkish Electricity Transmission temperature of 242°C, and prove the existence Company (TEİAŞ). As mentioned before, of a fourth, deeper and hotter reservoir Turkish Renewable Energy Law secures the (>250°C). purchase of electricity produced from Drillings for these new wells are scheduled renewable energy resources. Hence, it is to start by the last quarter of 2009. For this anticipated that main consumers of the purpose, a detailed drilling budget is prepared; electricity generated from this power main procurement items and contractual production operation will be the Provinces of services are being identified; and a work plan is Aydın, Denizli, and Kütahya, and the electricity being prepared.

7 Proceedings of the International Conference on NATIONAL DEVELOPMENT OF GEOTHERMAL ENERGY USE and International Course/EGEC Busiess Seminar on ORGANIZATION OF SUCCESSFUL DEVELEOPMENT OF A GEOTHERMAL PROJECT, K. Popovski, A.Vranovska, S. Popovska Vasilevska, Editors will be purchased by State Electricity Genera- of the CaCO3 scale inhibitor process on the tion Company (EÜAŞ). other hand is completed, and installation of the inhibitor injection system is on the way 4. Current Site Activities (equipment is ordered, installation is expected Zorlu has acquired the operation license of to be done in 2009 May). Re-injection the current 17.4 MWe Power Plant along with rehabilitation work plans are continuing, and the exploitation license of the field, and by law, unused production wells are being prepared for is obliged to operate the Power Plant with re-injection instead of drilling new wells. In this maximum efficiency. re-injection frame work over has started and is Following the acquisition of the Field, the continuing. The related well production increase in the efficiency of the Power Plant parameters can be observed in Figure 3. can be observed clearly: While before Mechanical Cleaning of Production Wells privatization the Plant was operated with a KD-13, KD-14, KD-15, KD-6, KD-20 KD-21, capacity of 5.4 MWe, at the moment its average KD-22 and R-1 wells’ cleanup facilities are capacity is 15 MWe. To keep the efficiency at performed by MTA with the assistance of this level, Zorlu gives outmost importance to Petrogas. Well cleaning operation and testing of the maintenance of the current wells. In this the production well is in progress. regard, the mechanical cleaning of the 9 production wells is still in progress. Selection

Figure 3. Well production parameters

Figure 4. CaCo3 scaling formed in KD 13.

8 Session 1 GEOTHERMALL ELECTRICITY PRODUCTION: POSSIBILITIES, TECHNICAL AND ECONOMIC FEASIBILITY IN CENTRAL EUROPEAN REGION Tevfik Kaya: KIZILDERE – NEW GEOTHERMAL POWER PLANT IN TURKEY

CaCo3 scaling formed in the production fluid in reservoir (1250 ton/hour) will be re- wells and surface facilities is cleaned by injected to 6 reinjection wells. Cleanup and mechanical reaming and (HCl) acidizing development surveys for this purpose are still operations. To prevent CaCO3 scaling in going on. Simulation studies are conducted in production wells; 10 different inhibitors of 8 order to determine the injectivity indexes of re- different companies from Italy, Germany, USA injection wells and as a result of this study, and Turkey are tested. Tests were started at 24 wells which can be used for this purpose are November 2008; and completed in a month determined and are being improved. Also, the successfully. For the inhibitor test existing contract is awarded for surface facility design wellhead equipment, down hole equipments and finalized. and injection system was overviewed and Turkey’s highest capacity 60 Mwe geo- prepared for the test. As a result of these thermal power plant is going to be constructed studies, it is observed that 5 of the inhibitors are in Kızıldere in a few years by Zorlu Holding. succeeded in preventing scaling. Not only the current activities in the field such Re-injection Studies Re-injection is as mechanical cleaning of wells and reinjection indispensable to preserve the reservoir balance. studies but also the prospective exploration In this regard, a re-injection action plan was activities by gathering the geoscience disci- prepared. The studies are continued to re-inject plines like geology, geophysics, geochemistry the remaining part of the geothermal fluid, after and reservoir, Kizildere geothermal project is the separation of the steam. going to addressed as a unique example and Simulation of Current Potential Re-injection leader in Turkey geothermal milestone. Wells Within the scope of this work, produced

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