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Renewable energy potential as an alternative to fossil fuels in Turkey
PERGAMON
Energy Conversion & Management 40 (1999) 743±755
Renewable energy potential as an alternative to fossil fuels in Turkey Volkan S° . Ediger a, Elc° in Kentel b a
Turkish Petroleum Corp., Mustafa Kemal Mah. No. 2, 06520 Ankara, Turkey b NigÆde University, Aksaray Engineering Faculty, 68100 Aksaray, Turkey Received 8 November 1997
Abstract Clean, domestic and renewable energy is commonly accepted as the key for future life, not only for Turkey but also for the world. All nations, regardless of their degree of development, are trying to develop and apply technologies that will enable them to use renewable energy sources in the most ecient ways. Turkey's geographical location has several advantages for extensive use of most of these sources. Because of this and the fact that it has limited fossil fuel resources, a gradual shift from fossil fuels to renewables seems to be serious and the sole alternative for the country. Turkey's renewable energy source potential and their present use are here evaluated based on the available data. # 1999 Elsevier Science Ltd. All rights reserved. Keywords: Renewable energy; Biomass; Hydropower; Geothermal; Solar; Wind; Turkey
1. Introduction Turkey's geographic location has several advantages for extensive use of most of the renewable energy sources (Fig. 1). It is on the humid and warm climatic belt, which includes most of Europe, the near east and western Asia. A typical Mediterranean climate is predominant at most of its coastal areas, whereas the climate at the interior part between the mountains that are a part of the Alpine±Himalayan mountain belt is dry with typical steppe vegetation. This is mainly because the country is surrounded by seas at three sides: the Black sea at the north, the Marmara sea and Aegean sea to the west and the Mediterranean sea to the south. Clean, domestic and renewable energy is commonly accepted as the key for future life, not only for Turkey but also for the world. This is primarily because renewable energy resources have some advantages when compared to fossil fuels. These advantages can be grouped under ``environmental concerns'' and ``limited resources.'' 0196-8904/99/$ - see front matter # 1999 Elsevier Science Ltd. All rights reserved. PII: S 0 1 9 6 - 8 9 0 4 ( 9 8 ) 0 0 1 2 2 - 8
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Fig. 1. Geographic location of Turkey. The stippled area depicts the humid and warm climatic belt extending between Europe and western Asia.
SO2, NOx, CO2, particulate matter and other emissions cause critical environmental problems, as they reach levels which allow long range or cross country transport of these pollutants. Turkey receives signals from international sources, being among the rare countries which have not reduced NOx and sul®de emissions in 1992 with respect to the 1980 s. It could not sign the ``Climate Change Agreement'' because it had six power plants on the list of ``100 sources which cause highest sul®de emissions in Europe'' [1]. These environmental facts force Turkey to take some measures covering clean fuel consumption, application of emission control technologies and conservation of energy consumption on personal and community bases. Although Turkey has almost all kinds of energy resources, it is an energy importing country, since these resources are limited [2]. More than half of the primary energy consumption in Turkey is met by imports and the share of imports continues to increase each year. Therefore, it seems that, if the country wants to supply its demand by domestic resources, being less dependent on foreign resources, a shift from conventional energy resources (i.e. fossil fuels, such as hard coal, lignite, oil and natural gas) to renewable energy resources must be realized in a reasonable time period. The total renewable energy production and consumption of Turkey are equal to each other, varying between 9.0±11.0 million toe each for the 1986±1995 period (Fig. 2). Their share in total energy production varies between 37.43±43.06% while in total consumption between 16.35±22.00% for the same period. Among the production of renewable energy sources, biomass, which includes wood and dung, is the highest in 1994, reaching 7.957 million toe. The second highest is hydro energy production which reached 3.057 million toe in 1995. The production of geothermal and solar energy is negligible compared to biomass and hydro power, varying from 43 to 190 thousand toe between 1986 and 1995. Wind energy almost does not have any application yet.
Fig. 2. Renewable energy consumption of Turkey between 1986±1995. Data from [2].
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V.S° . Ediger, E. Kentel / Energy Conversion & Management 40 (1999) 743±755 Table 1 Forest potential of Turkey. Data from [2, 3].
High productive (total) Forest Other woodlands Low productive (total) Forest Other woodlands Total
Resources (thousand m3)
Annual growth (thousand m3)
847,032 88,300 758,732 88,479 34,129 54,350 935,511
25,605 4,813 20,792 2,459 1,115 1,344 28,064
These are the reasons why the authors of this paper tried to determine objectively the renewable energy potential of Turkey. For this purpose, all previous data are collected and evaluated. Reserves and limited applications of each renewable energy resource, such as biomass, hydro, geothermal, solar and wind, in the country will be explained in the following sections separately.
2. Biomass energy Biomass potential includes wood and other animal and plant wastes. However, the wood fuel production is not as high as expected, since forests are rapidly being reduced in Turkey due to overtimbering and deforestation (Table 1). The total forest potential of Turkey is around 935 million m3 with an annual growth of about 28 million m3 (Table 1). The average annual growth rate of the forests is about 3%. Around 90% of this potential includes high productive forests and other woodlands, the others being low productive forests and other woodlands. Energy forests seem to be the best solution, and it has been estimated that 5 million hectares of productive forest land is available to be used as energy forests in Turkey [2, 3]. Table 2 Distribution of biogas potential of Turkey. Data from [4]. Biogass potential (m3/year) Dung gas Cattle (43,102,800 tons dung) Sheep (28,303,100 tons dung) Poultry (3,062,554 tons dung) Land®ll gas Total biogas*
3,302,851,412 m3/year 1,422,392,400 m3/year 1,641,579,800 m3/year 238,879,212 m3/year 600,000,000 m3/year 3,902,851,412 m3/year
*Provided that all dung is used for biogas production
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Biogas, which is the fermentation product of animal dung, has a potential between 2.2±3.9 billion m3 per year, corresponding to 1±2 million toe provided that all dung is used for biogas production [2, 4, 5]. Around 85% of the total biogas potential is from dung gas, and the remainder is from land®ll gas (Table 2). The dung gas potential is obtained from 50% sheep, 43% cattle and 7% poultry. It is calculated that an average of 80±100 ton wet biomass (25±30 ton usable biomass) per hectare can be obtained in the Central Anatolian region [6]. The overall bioenergy potential of Turkey is estimated to be 17.2 million toe [7]. However, this estimate is based on the recoverable energy potential from the main agricultural residues, livestock farming wastes, forestry, wood processing residues and municipal wastes. Biomass resources have been used essentially for cooking and heating purposes, especially in rural areas in Turkey. The use of animal wastes as biofuel is limited, because they are mostly used in agriculture as fertilizers. The only waste power plant of the country is in Adana, and was built in 1991 [8]. Land®ll gas has been used only occasionally as an energy resource in Turkey.
3. Hydro power Annual rainfall in Turkey varies between 220 mm to 2500 mm with an average of about 643 mm, and most of the hydro power plants are in the regions receiving an average annual rainfall of more than 500 mm (Fig. 3). Also, as can easily be observed from the map, most of the hydro power plants are located away from the heavy demand centers of the Istanbul± Ankara axis in the northwest of Turkey. Because of this geographic location of its generating
Fig. 3. Map depicting hydro power plants in operation in Turkey. Data from [9].
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V.S° . Ediger, E. Kentel / Energy Conversion & Management 40 (1999) 743±755 Table 3 Hydro power potential of Turkey. Data from [2, 9].
Gross potential Economically usable potential Exploited potential (total in operation) Dams and HEPPs* Run-o river & canal HEPPs
Power (mw)
Electricity generation (gwh/year)
49,427 34,736 9,865 9,349 516
433,000 125,000 36,000 33,518 2,482
*Hydro Electric Power Plants
potential, Turkey has a de®ciency of electricity in the west but has been able to export power in the east. According to recent studies, the economically usable potential of electricity generation of Turkey is estimated as 125,000 GWh per year (Table 3). This ®gure corresponds to around 29% of the gross potential of electricity generation from hydro power. The total installed hydro power capacity of Turkey reached 9,865 MW in 1995. This ®gure corresponds to around 28.5% of the economically usable power potential. About 95% of the already exploited potential is from dams and hydroelectric power plants (HEPP), and the remainder is from runo river and canal HEPPs. In addition to the dams and run-o rivers and canals in operation, several others are in various stages, such as under construction, ®nal design completed and ®nal design in progress (Table 4). The total installed capacity of them is 8,820 MW. Following completion of their construction, the total amount of exploited potential will reach 18,685 MW, consisting of about 54% of the economically usable potential. The annual electricity generation will then reach 63,969 GWh which will consist of about 51% of the economically usable potential. Table 4 Potentials of hydroplants under construction and at various stages. Data from [9].
Dams (under construction) Dams (®nal design completed) Dams (®nal design in progress) Run-o river & canal (under construction) Run-o river & canal (®nal design completed) Run-o river & canal (®nal design in progress) Total
Installed capacity (mw)
Electricity generation (gwh/year)
3,092 4,284 926 111 284 123 8,820
9,809 12,898 3,279 406 1,101 476 27,969
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Fig. 4. Geothermal ®elds having temperatures greater than 1008C. Data from [2, 10±20].
4. Geothermal energy Turkey is situated on the Alpine±Himalayan orogenic belt and the Miocene or younger grabens are developed as the result of this orogeny. Wide spread volcanism, fumarole hydrothermal alterations and the existence of more than 600 hot springs, some of which have 1008C and greater temperatures, indicate that Turkey has an important geothermal energy potential (Fig. 4). The overall geothermal potential of Turkey is about 38,000 MW (Table 5). Around 88% of this potential is appropriate for thermal use (low enthalpy ®elds with temperature less than 2008C) and the remainder for electricity production (high enthalpy ®elds with temperature more than 2008C). Only 7.2% of the low enthalpy ®elds and 4.4% of the high enthalpy ®elds are proven, and the remainder is probable and possible reserve. In spite of geothermal energy being a relatively new energy for Turkey, when compared with other energy resources, it is utilized for various purposes, such as for electricity production, Table 5 Geothermal potential of Turkey. Data from [2, 12, 13].
Heat (<2008C, low enthalpy ®elds) Electricity (>2008C, high enthalpy ®elds)
Proven (mw)
Probable & possible (mw)
2,250 MWt 200 MWe
31,100 MWt 4,500 MWe
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space heating and touristic installations (Fig. 4). The only geothermal power plant of Turkey was installed in the K|z|ldere (Denizli) ®eld in February 1984, sixteen years later than the drilling of the ®rst borehole as a result of a project supported by UNDP in 1968 [2, 8, 10± 15, 21]. The installed capacity of this power plant is 20.4 MW. In addition, a factory with a capacity of 40,000 tons/year is continuing to extract CO2 gas from the steam to meet the demand of domestic industry. Greenhouses of approximately 5,000 m2 have been heated by using waste water of the plant [10, 11]. Greenhouse and dwelling heating installations also exist in various locations in Turkey. For example, the Balc° ova (IÇ zmir) geothermal ®eld (Fig. 4) has been used for the thermal installations of Balc° ova and for some units of the 9 EyluÈl University [10, 12±14, 22]. 2,000 m2 of greenhouse and 1,600 dwellings are heated by geothermal energy in GoÈnen-Bal|kesir [10, 13, 23]. Apart from the utilizations given above, greenhouses of 1,000 m2 in C° anakkale [10], 6,900 m2 in Havran± Bal|kesir [10], 3,000 m2 in Tekkehamam±Denizli [10], 6,000 m2 in Seferihisar±IÇ zmir [23], 10,000 m2 in SaraykoÈy±Denizli [23], 5,000 m2 in Germencik±Ayd|n [23], 1,750 m2 in S|nd|rgi± Bal|kesir [23] and 22,705 m2 in Edremit±Bal|kesir [23] are heated by geothermal energy. 5. Solar energy Solar energy, being the oldest energy source used by mankind, is the cleanest and most abundant one among others. Turkey's geographical location is highly favorable for utilization of solar energy (Fig. 1). It is well known that climatic data can not be used for solar feasibility studies for the determination of possible locations for power generation installations. To provide appropriate
Fig. 5. Map depicting distribution of sunshine duration and solar radiation in Turkey. Data from [24].
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Table 6 Solar radiation and sunshine duration by regions of Turkey. Data from [2, 3, 8, 24±30].
Southeast Anatolia Mediterranean East Anatolia Central Anatolia Aegean Marmara Black Sea Turkey Average
Solar radiation (cal/cm2.day)
Sunshine duration (hour/day)
344.8 328.3 322.4 310.3 308.0 275.9 264.5 309.6
8.2 8.1 7.3 7.2 7.5 6.6 5.4 7.2
data, solar data acquisition systems were installed in ®ve dierent locations of Turkey by the Electrical Power Resources Survey and Development Administration (EIÇ EIÇ ). According to solar radiation and sunshine duration distribution maps by this administration in 1983, solar radiation and sunshine duration vary between about 240±395 cal/cm2 day and 4.5±8.5 h/day, respectively (Fig. 5). The average solar radiation is 309.6 cal/cm2 day, and the average sunshine duration is 7.2 h/day (Table 6). The southeast Anatolia region is the most favorable region for solar energy use with an average solar radiation of 344.8 cal/cm2 day and sunshine duration of 8.2 h/day. The southern part of the Erzurum±Ankara line have more than the average solar radiation (Fig. 5). The gross solar potential of Turkey is calculated as 88 billion toe per year, of which 40% can be used economically [2, 3, 25]. Three-fourths of the economically usable potential is ecient for thermal use (26.4 billion toe per year) and the remainder for electricity production (8.8 billion toe per year). Since the technology necessary for its conversion into more practical energy forms for daily use has not reached the economically feasible level, solar power applications are limited, both in Turkey and in the world. For Turkey, the ®rst recorded data about solar energy use, which was only 5,000 toe, was in 1986. It increased more than 10 times, reaching 52,000 toe in 1995 [2]. Among the three applications of solar energy (i.e. photovoltaic, thermoelectricity and thermal), thermal is the most commonly used one for producing hot water in the south and west of Turkey. A total of 19 million m2 of ¯at plate collectors are produced by about 40 dierent companies in Turkey in 1995 [2, 31]. Some other applications, such as irrigation pumps, lighting of various places and cathodic protection against corrosion, are negligible when compared to applications for heating purposes [8, 32±34]. 6. Wind energy The most attractive regions for wind energy applications are the Marmara, Southeast Anatolian and Aegean according to data by EiEi's wind energy data acquisition stations at
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Fig. 6. Regions where wind speed exceeds 3 m/s and wind density distribution of Turkey. Data from [35].
various locations (Fig. 6, Table 7). These regions are highly suitable for wind power generation, since wind speeds exceed 3 m/s in most of these areas. Old wind mills found in the Marmara and Aegean regions are good indicators of the wind energy potential for these regions [37]. The highest wind speed values are given in the literature as 5.1±5.2 m/s in Bandirma [14, 36± 38], 6.3±7.0 m/s in Bozcaada [8, 14, 35, 40, 41], 6.4 m/s in Karaburun [36], 6.4 m/s in Karabiga [36], 7.1 m/s in NurdagÆi [36], 7.3 m/s in S° enkoÈy [36]. The already recorded highest wind densities are 152.6 watt/m2 in Band|rma [37, 38] and 108.9 watt/m2 in Antakya [37, 38]. Table 7 Wind potential by regions of Turkey. Data form [2, 3, 36±39].
Marmara Southeast Anatolia Aegean Mediterranean Black Sea Central Anatolia East Anatolia Turkey Average
Annual average wind density (watt/m2)
Annual average wind speed (m/s)
51.9 29.3 23.5 21.4 21.3 20.1 13.2 24.0
3.3 2.7 2.6 2.5 2.4 2.5 2.1 2.5
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The gross wind energy potential of Turkey is more than 400 billion kWh, of which 124 billion kWh is technically feasible potential, and for some speci®c locations, the net economic potential reaches about 14 billion kWh [38]. The world has approximately 2,500 MW installed capacity, most of which is in the USA and Denmark [2, 42]. However, although some research is continued by EiEi, Tubitak Marmara Research Institute, the Middle East Technical University and some others, there has not been any comprehensive application. The only electricity generator in use in Turkey is in C° es° me-IÇ zmir and it has 55 kWh energy [8, 38].
7. Concluding remarks Using traditional sources and fossil fuels for energy results in smog on the local scale, acid rain on a regional scale and an enhanced greenhouse eect on a global scale [43]. The negative economic value of the damage which is estimated to be around $454 per capita should be already an alarming signal for consumption of fossil fuels [44]. All nations, regardless of their degree of development, are faced with improving a cleaner and, therefore, less contaminating technology for the use of renewable energy sources [45]. Environmental concerns emerging in the late 1980 s and high oil prices in the 1990 s are certain to stimulate new eorts in shifting the source of energy supply from exhaustible to renewable energy [46]. Due to some technological and economical consequences, renewable energy resources do not have wide applications neither in the world nor in Turkey at present. Besides, with the existing technology, it does not seem possible to supply the total demand of any country from renewable sources [46, 47]. However, a step-wise (i.e. combined use) shift from fossil fuels to renewable ones seems to be serious and the sole alternative also for Turkey, which considers itself as an integrated part of the world system.
Acknowledgements The authors would like to thank the Turkish Petroleum Corporation and the NigÆde University for permission to publish this paper. Appreciation is also due the Solar and Wind Energy Departments of the Electrical Power Resources Survey and Development Administration (EIÇ EIÇ ) for providing data, particularly related to the solar and wind energy potential of Turkey.
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Energy Conversion & Management 40 (1999) 743±755
Renewable energy potential as an alternative to fossil fuels in Turkey Volkan S° . Ediger a, Elc° in Kentel b a
Turkish Petroleum Corp., Mustafa Kemal Mah. No. 2, 06520 Ankara, Turkey b NigÆde University, Aksaray Engineering Faculty, 68100 Aksaray, Turkey Received 8 November 1997
Abstract Clean, domestic and renewable energy is commonly accepted as the key for future life, not only for Turkey but also for the world. All nations, regardless of their degree of development, are trying to develop and apply technologies that will enable them to use renewable energy sources in the most ecient ways. Turkey's geographical location has several advantages for extensive use of most of these sources. Because of this and the fact that it has limited fossil fuel resources, a gradual shift from fossil fuels to renewables seems to be serious and the sole alternative for the country. Turkey's renewable energy source potential and their present use are here evaluated based on the available data. # 1999 Elsevier Science Ltd. All rights reserved. Keywords: Renewable energy; Biomass; Hydropower; Geothermal; Solar; Wind; Turkey
1. Introduction Turkey's geographic location has several advantages for extensive use of most of the renewable energy sources (Fig. 1). It is on the humid and warm climatic belt, which includes most of Europe, the near east and western Asia. A typical Mediterranean climate is predominant at most of its coastal areas, whereas the climate at the interior part between the mountains that are a part of the Alpine±Himalayan mountain belt is dry with typical steppe vegetation. This is mainly because the country is surrounded by seas at three sides: the Black sea at the north, the Marmara sea and Aegean sea to the west and the Mediterranean sea to the south. Clean, domestic and renewable energy is commonly accepted as the key for future life, not only for Turkey but also for the world. This is primarily because renewable energy resources have some advantages when compared to fossil fuels. These advantages can be grouped under ``environmental concerns'' and ``limited resources.'' 0196-8904/99/$ - see front matter # 1999 Elsevier Science Ltd. All rights reserved. PII: S 0 1 9 6 - 8 9 0 4 ( 9 8 ) 0 0 1 2 2 - 8
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Fig. 1. Geographic location of Turkey. The stippled area depicts the humid and warm climatic belt extending between Europe and western Asia.
SO2, NOx, CO2, particulate matter and other emissions cause critical environmental problems, as they reach levels which allow long range or cross country transport of these pollutants. Turkey receives signals from international sources, being among the rare countries which have not reduced NOx and sul®de emissions in 1992 with respect to the 1980 s. It could not sign the ``Climate Change Agreement'' because it had six power plants on the list of ``100 sources which cause highest sul®de emissions in Europe'' [1]. These environmental facts force Turkey to take some measures covering clean fuel consumption, application of emission control technologies and conservation of energy consumption on personal and community bases. Although Turkey has almost all kinds of energy resources, it is an energy importing country, since these resources are limited [2]. More than half of the primary energy consumption in Turkey is met by imports and the share of imports continues to increase each year. Therefore, it seems that, if the country wants to supply its demand by domestic resources, being less dependent on foreign resources, a shift from conventional energy resources (i.e. fossil fuels, such as hard coal, lignite, oil and natural gas) to renewable energy resources must be realized in a reasonable time period. The total renewable energy production and consumption of Turkey are equal to each other, varying between 9.0±11.0 million toe each for the 1986±1995 period (Fig. 2). Their share in total energy production varies between 37.43±43.06% while in total consumption between 16.35±22.00% for the same period. Among the production of renewable energy sources, biomass, which includes wood and dung, is the highest in 1994, reaching 7.957 million toe. The second highest is hydro energy production which reached 3.057 million toe in 1995. The production of geothermal and solar energy is negligible compared to biomass and hydro power, varying from 43 to 190 thousand toe between 1986 and 1995. Wind energy almost does not have any application yet.
Fig. 2. Renewable energy consumption of Turkey between 1986±1995. Data from [2].
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V.S° . Ediger, E. Kentel / Energy Conversion & Management 40 (1999) 743±755 Table 1 Forest potential of Turkey. Data from [2, 3].
High productive (total) Forest Other woodlands Low productive (total) Forest Other woodlands Total
Resources (thousand m3)
Annual growth (thousand m3)
847,032 88,300 758,732 88,479 34,129 54,350 935,511
25,605 4,813 20,792 2,459 1,115 1,344 28,064
These are the reasons why the authors of this paper tried to determine objectively the renewable energy potential of Turkey. For this purpose, all previous data are collected and evaluated. Reserves and limited applications of each renewable energy resource, such as biomass, hydro, geothermal, solar and wind, in the country will be explained in the following sections separately.
2. Biomass energy Biomass potential includes wood and other animal and plant wastes. However, the wood fuel production is not as high as expected, since forests are rapidly being reduced in Turkey due to overtimbering and deforestation (Table 1). The total forest potential of Turkey is around 935 million m3 with an annual growth of about 28 million m3 (Table 1). The average annual growth rate of the forests is about 3%. Around 90% of this potential includes high productive forests and other woodlands, the others being low productive forests and other woodlands. Energy forests seem to be the best solution, and it has been estimated that 5 million hectares of productive forest land is available to be used as energy forests in Turkey [2, 3]. Table 2 Distribution of biogas potential of Turkey. Data from [4]. Biogass potential (m3/year) Dung gas Cattle (43,102,800 tons dung) Sheep (28,303,100 tons dung) Poultry (3,062,554 tons dung) Land®ll gas Total biogas*
3,302,851,412 m3/year 1,422,392,400 m3/year 1,641,579,800 m3/year 238,879,212 m3/year 600,000,000 m3/year 3,902,851,412 m3/year
*Provided that all dung is used for biogas production
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Biogas, which is the fermentation product of animal dung, has a potential between 2.2±3.9 billion m3 per year, corresponding to 1±2 million toe provided that all dung is used for biogas production [2, 4, 5]. Around 85% of the total biogas potential is from dung gas, and the remainder is from land®ll gas (Table 2). The dung gas potential is obtained from 50% sheep, 43% cattle and 7% poultry. It is calculated that an average of 80±100 ton wet biomass (25±30 ton usable biomass) per hectare can be obtained in the Central Anatolian region [6]. The overall bioenergy potential of Turkey is estimated to be 17.2 million toe [7]. However, this estimate is based on the recoverable energy potential from the main agricultural residues, livestock farming wastes, forestry, wood processing residues and municipal wastes. Biomass resources have been used essentially for cooking and heating purposes, especially in rural areas in Turkey. The use of animal wastes as biofuel is limited, because they are mostly used in agriculture as fertilizers. The only waste power plant of the country is in Adana, and was built in 1991 [8]. Land®ll gas has been used only occasionally as an energy resource in Turkey.
3. Hydro power Annual rainfall in Turkey varies between 220 mm to 2500 mm with an average of about 643 mm, and most of the hydro power plants are in the regions receiving an average annual rainfall of more than 500 mm (Fig. 3). Also, as can easily be observed from the map, most of the hydro power plants are located away from the heavy demand centers of the Istanbul± Ankara axis in the northwest of Turkey. Because of this geographic location of its generating
Fig. 3. Map depicting hydro power plants in operation in Turkey. Data from [9].
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V.S° . Ediger, E. Kentel / Energy Conversion & Management 40 (1999) 743±755 Table 3 Hydro power potential of Turkey. Data from [2, 9].
Gross potential Economically usable potential Exploited potential (total in operation) Dams and HEPPs* Run-o river & canal HEPPs
Power (mw)
Electricity generation (gwh/year)
49,427 34,736 9,865 9,349 516
433,000 125,000 36,000 33,518 2,482
*Hydro Electric Power Plants
potential, Turkey has a de®ciency of electricity in the west but has been able to export power in the east. According to recent studies, the economically usable potential of electricity generation of Turkey is estimated as 125,000 GWh per year (Table 3). This ®gure corresponds to around 29% of the gross potential of electricity generation from hydro power. The total installed hydro power capacity of Turkey reached 9,865 MW in 1995. This ®gure corresponds to around 28.5% of the economically usable power potential. About 95% of the already exploited potential is from dams and hydroelectric power plants (HEPP), and the remainder is from runo river and canal HEPPs. In addition to the dams and run-o rivers and canals in operation, several others are in various stages, such as under construction, ®nal design completed and ®nal design in progress (Table 4). The total installed capacity of them is 8,820 MW. Following completion of their construction, the total amount of exploited potential will reach 18,685 MW, consisting of about 54% of the economically usable potential. The annual electricity generation will then reach 63,969 GWh which will consist of about 51% of the economically usable potential. Table 4 Potentials of hydroplants under construction and at various stages. Data from [9].
Dams (under construction) Dams (®nal design completed) Dams (®nal design in progress) Run-o river & canal (under construction) Run-o river & canal (®nal design completed) Run-o river & canal (®nal design in progress) Total
Installed capacity (mw)
Electricity generation (gwh/year)
3,092 4,284 926 111 284 123 8,820
9,809 12,898 3,279 406 1,101 476 27,969
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Fig. 4. Geothermal ®elds having temperatures greater than 1008C. Data from [2, 10±20].
4. Geothermal energy Turkey is situated on the Alpine±Himalayan orogenic belt and the Miocene or younger grabens are developed as the result of this orogeny. Wide spread volcanism, fumarole hydrothermal alterations and the existence of more than 600 hot springs, some of which have 1008C and greater temperatures, indicate that Turkey has an important geothermal energy potential (Fig. 4). The overall geothermal potential of Turkey is about 38,000 MW (Table 5). Around 88% of this potential is appropriate for thermal use (low enthalpy ®elds with temperature less than 2008C) and the remainder for electricity production (high enthalpy ®elds with temperature more than 2008C). Only 7.2% of the low enthalpy ®elds and 4.4% of the high enthalpy ®elds are proven, and the remainder is probable and possible reserve. In spite of geothermal energy being a relatively new energy for Turkey, when compared with other energy resources, it is utilized for various purposes, such as for electricity production, Table 5 Geothermal potential of Turkey. Data from [2, 12, 13].
Heat (<2008C, low enthalpy ®elds) Electricity (>2008C, high enthalpy ®elds)
Proven (mw)
Probable & possible (mw)
2,250 MWt 200 MWe
31,100 MWt 4,500 MWe
750
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space heating and touristic installations (Fig. 4). The only geothermal power plant of Turkey was installed in the K|z|ldere (Denizli) ®eld in February 1984, sixteen years later than the drilling of the ®rst borehole as a result of a project supported by UNDP in 1968 [2, 8, 10± 15, 21]. The installed capacity of this power plant is 20.4 MW. In addition, a factory with a capacity of 40,000 tons/year is continuing to extract CO2 gas from the steam to meet the demand of domestic industry. Greenhouses of approximately 5,000 m2 have been heated by using waste water of the plant [10, 11]. Greenhouse and dwelling heating installations also exist in various locations in Turkey. For example, the Balc° ova (IÇ zmir) geothermal ®eld (Fig. 4) has been used for the thermal installations of Balc° ova and for some units of the 9 EyluÈl University [10, 12±14, 22]. 2,000 m2 of greenhouse and 1,600 dwellings are heated by geothermal energy in GoÈnen-Bal|kesir [10, 13, 23]. Apart from the utilizations given above, greenhouses of 1,000 m2 in C° anakkale [10], 6,900 m2 in Havran± Bal|kesir [10], 3,000 m2 in Tekkehamam±Denizli [10], 6,000 m2 in Seferihisar±IÇ zmir [23], 10,000 m2 in SaraykoÈy±Denizli [23], 5,000 m2 in Germencik±Ayd|n [23], 1,750 m2 in S|nd|rgi± Bal|kesir [23] and 22,705 m2 in Edremit±Bal|kesir [23] are heated by geothermal energy. 5. Solar energy Solar energy, being the oldest energy source used by mankind, is the cleanest and most abundant one among others. Turkey's geographical location is highly favorable for utilization of solar energy (Fig. 1). It is well known that climatic data can not be used for solar feasibility studies for the determination of possible locations for power generation installations. To provide appropriate
Fig. 5. Map depicting distribution of sunshine duration and solar radiation in Turkey. Data from [24].
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Table 6 Solar radiation and sunshine duration by regions of Turkey. Data from [2, 3, 8, 24±30].
Southeast Anatolia Mediterranean East Anatolia Central Anatolia Aegean Marmara Black Sea Turkey Average
Solar radiation (cal/cm2.day)
Sunshine duration (hour/day)
344.8 328.3 322.4 310.3 308.0 275.9 264.5 309.6
8.2 8.1 7.3 7.2 7.5 6.6 5.4 7.2
data, solar data acquisition systems were installed in ®ve dierent locations of Turkey by the Electrical Power Resources Survey and Development Administration (EIÇ EIÇ ). According to solar radiation and sunshine duration distribution maps by this administration in 1983, solar radiation and sunshine duration vary between about 240±395 cal/cm2 day and 4.5±8.5 h/day, respectively (Fig. 5). The average solar radiation is 309.6 cal/cm2 day, and the average sunshine duration is 7.2 h/day (Table 6). The southeast Anatolia region is the most favorable region for solar energy use with an average solar radiation of 344.8 cal/cm2 day and sunshine duration of 8.2 h/day. The southern part of the Erzurum±Ankara line have more than the average solar radiation (Fig. 5). The gross solar potential of Turkey is calculated as 88 billion toe per year, of which 40% can be used economically [2, 3, 25]. Three-fourths of the economically usable potential is ecient for thermal use (26.4 billion toe per year) and the remainder for electricity production (8.8 billion toe per year). Since the technology necessary for its conversion into more practical energy forms for daily use has not reached the economically feasible level, solar power applications are limited, both in Turkey and in the world. For Turkey, the ®rst recorded data about solar energy use, which was only 5,000 toe, was in 1986. It increased more than 10 times, reaching 52,000 toe in 1995 [2]. Among the three applications of solar energy (i.e. photovoltaic, thermoelectricity and thermal), thermal is the most commonly used one for producing hot water in the south and west of Turkey. A total of 19 million m2 of ¯at plate collectors are produced by about 40 dierent companies in Turkey in 1995 [2, 31]. Some other applications, such as irrigation pumps, lighting of various places and cathodic protection against corrosion, are negligible when compared to applications for heating purposes [8, 32±34]. 6. Wind energy The most attractive regions for wind energy applications are the Marmara, Southeast Anatolian and Aegean according to data by EiEi's wind energy data acquisition stations at
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Fig. 6. Regions where wind speed exceeds 3 m/s and wind density distribution of Turkey. Data from [35].
various locations (Fig. 6, Table 7). These regions are highly suitable for wind power generation, since wind speeds exceed 3 m/s in most of these areas. Old wind mills found in the Marmara and Aegean regions are good indicators of the wind energy potential for these regions [37]. The highest wind speed values are given in the literature as 5.1±5.2 m/s in Bandirma [14, 36± 38], 6.3±7.0 m/s in Bozcaada [8, 14, 35, 40, 41], 6.4 m/s in Karaburun [36], 6.4 m/s in Karabiga [36], 7.1 m/s in NurdagÆi [36], 7.3 m/s in S° enkoÈy [36]. The already recorded highest wind densities are 152.6 watt/m2 in Band|rma [37, 38] and 108.9 watt/m2 in Antakya [37, 38]. Table 7 Wind potential by regions of Turkey. Data form [2, 3, 36±39].
Marmara Southeast Anatolia Aegean Mediterranean Black Sea Central Anatolia East Anatolia Turkey Average
Annual average wind density (watt/m2)
Annual average wind speed (m/s)
51.9 29.3 23.5 21.4 21.3 20.1 13.2 24.0
3.3 2.7 2.6 2.5 2.4 2.5 2.1 2.5
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The gross wind energy potential of Turkey is more than 400 billion kWh, of which 124 billion kWh is technically feasible potential, and for some speci®c locations, the net economic potential reaches about 14 billion kWh [38]. The world has approximately 2,500 MW installed capacity, most of which is in the USA and Denmark [2, 42]. However, although some research is continued by EiEi, Tubitak Marmara Research Institute, the Middle East Technical University and some others, there has not been any comprehensive application. The only electricity generator in use in Turkey is in C° es° me-IÇ zmir and it has 55 kWh energy [8, 38].
7. Concluding remarks Using traditional sources and fossil fuels for energy results in smog on the local scale, acid rain on a regional scale and an enhanced greenhouse eect on a global scale [43]. The negative economic value of the damage which is estimated to be around $454 per capita should be already an alarming signal for consumption of fossil fuels [44]. All nations, regardless of their degree of development, are faced with improving a cleaner and, therefore, less contaminating technology for the use of renewable energy sources [45]. Environmental concerns emerging in the late 1980 s and high oil prices in the 1990 s are certain to stimulate new eorts in shifting the source of energy supply from exhaustible to renewable energy [46]. Due to some technological and economical consequences, renewable energy resources do not have wide applications neither in the world nor in Turkey at present. Besides, with the existing technology, it does not seem possible to supply the total demand of any country from renewable sources [46, 47]. However, a step-wise (i.e. combined use) shift from fossil fuels to renewable ones seems to be serious and the sole alternative also for Turkey, which considers itself as an integrated part of the world system.
Acknowledgements The authors would like to thank the Turkish Petroleum Corporation and the NigÆde University for permission to publish this paper. Appreciation is also due the Solar and Wind Energy Departments of the Electrical Power Resources Survey and Development Administration (EIÇ EIÇ ) for providing data, particularly related to the solar and wind energy potential of Turkey.
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