renewable energy and sustainable development in turkey

Renewable Energy 25 (2002) 431–453www.elsevier.nl/locate/renene

Renewable energy and sustainable developmentin Turkey

Kamil Kaygusuza,*, Abdullah Kaygusuzb

a Department of Chemistry, Karadeniz Technical University, 61080 Trabzon, Turkeyb Department of Geological Engineering, Karadeniz Technical University, 61080 Trabzon, Turkey

Received 14 August 2000; accepted 14 February 2001

Abstract

Achieving solutions to environmental problems that we face today requires long-term poten-tial actions for sustainable development. In this regard, renewable energy resources appear tobe the one of the most efficient and effective solutions. So clean, domestic and renewableenergy is commonly accepted as the key for future life for Turkey. Turkey’s geographicallocation has several advantages for extensive use of most of these renewable energy sources.Because of this and the fact that it has limited fossil fuel resources, a gradual shift from fossilfuels to renewables seems to be serious and the sole alternative for Turkey. This article presentsa review of the present energy situation and sustainability, technical and economical potentialof renewable energy sources and future policies for the energy sector in Turkey. Also, potentialsolutions to current environmental problems are identified along with renewable energy techno-logies. Throughout the paper several problems relating to renewable energy sources, environ-ment and sustainable development are discussed from both current and future perspectives.The renewable energy potential of the country and their present use are evaluated here basedon the available data. The present study shows that there is an important potential for renew-ables in Turkey. 2001 Elsevier Science Ltd. All rights reserved.

1. Introduction

Energy is considered a prime agent in the generation of wealth and also a signifi-cant factor in economic development. The importance of energy in economic devel-opment has been recognized almost universally, the historical data attest to a strongrelationship between the availability of energy and economic activity. During the

* Corresponding author. Fax:+90-462-325-3195.E-mail address: [email protected] (K. Kaygusuz).

0960-1481/02/$ - see front matter 2001 Elsevier Science Ltd. All rights reserved.PII: S0960 -1481(01 )00075-1

432 K. Kaygusuz, A. Kaygusuz / Renewable Energy 25 (2002) 431–453

Nomenclature

COP heat pump coefficient of performancef fraction of the load met by free energy (%)I monthly-average hourly global radiation on horizontal surface

(W/m2)ID monthly-average hourly diffuse radiation on horizontal surface

(W/m2)I0 monthly-average hourly extraterrestrial radiation on horizontal

surface (W/m2)kton thousand tonnesktoe thousand tonnes of oil equivalentRH relative humidity (%)Q heating load of the building (kW)Ta ambient air temperature (°C)N number of working days of the series heat pump system per monthhcol collector efficiencyhst storage efficiencyYDD yearly degree days

past two decades the risk and reality of environmental degradation have becomemore apparent. Growing evidence of environmental problems is due to a combinationof several factors since the environmental impact of human activities has growndramatically because of the sheer increase of world population, consumption, indus-trial activity, etc. Achieving solutions to environmental problems that we face todayrequires long-term potential actions for sustainable development. In this regard,renewable energy resources appear to be the one of the most efficient and effectivesolutions. That is why there is an intimate connection between renewable energyand sustainable development [1].

The Kyoto Protocol to the United Nations Framework Convention on ClimateChange, agreed to in December 1997, marks an important turning point in effortsto promote the use of renewable energy worldwide. Since the original FrameworkConvention was signed at the Earth Summit in Rio de Janeiro in 1992, climatechange has spurred many countries to step up their support of renewable energy.Even more ambitious efforts to promote renewables can be expected as a result ofthe Kyoto pact, which includes legally binding emissions limits for industrial coun-tries, for the first time, specially identifies promotion of renewable energy as a keystrategy for reducing greenhouse gas emissions [2].

Coal, oil, and natural gas are all fossil fuels that were formed millions or evenhundreds of millions of years ago from decaying prehistoric plants and animals.Although fossil fuels are still being created today by underground heat and pressure,they are consumed much more rapidly than they are created. Fossil fuels are non-

433K. Kaygusuz, A. Kaygusuz / Renewable Energy 25 (2002) 431–453

renewable, meaning that they draw on finite resources that will eventually dwindle,becoming too expensive or too environmentally damaging to retrieve. The searchfor new reserves of fossil fuels has already led to oil drilling along ocean coasts andother environmentally sensitive areas [3].

Sunlight can be used directly for heating and lighting residential and commercialbuildings. The heat of the sun can be harnessed for hot water heating, solar cooling,and other commercial and industrial uses. The sun’s heat can also be used to generateelectricity, using a technology called solar thermal electric power. Sunlight can alsobe converted directly to electricity using photovoltaic solar cells. Many other formsof renewable energy are indirectly powered by the sun. For example, the sun’s heatdrives the winds which produce energy that is captured with wind turbines. Winds,in turn, cause ocean waves, producing energy that can be converted to electricity.Sunlight also causes plants to grow, the energy stored in those plants is known asbiomass energy (wood, straw, dung, and other plant wastes). Biomass can be con-verted to liquid or gaseous fuels or burned to produce electricity [3].

Renewable energy resources (solar, hydroelectric, biomass, wind, ocean and geo-thermal energy) are inexhaustible and offer many environmental benefits over con-ventional energy sources. Each type of renewable energy also has its own specialadvantages that make it uniquely suited to certain applications. Almost none of themreleases gaseous or liquid pollutants during operation. In their technological develop-ment, the renewables range from technologies that are well established and matureto those that need further research and development [3].

Turkey’s geographic location has several advantages for extensive use of most ofthe renewable energy sources. It is on the humid and warm climatic belt whichincludes most of Europe, the near east and western Asia. A typical Mediterraneanclimate is predominant at most of its coastal areas, whereas the climate at the interiorpart between the mountains that are a part of the Alpine–Himalayan mountain beltis dry with typical steppe vegetation. This is mainly because the country is sur-rounded by seas at three sides: the Black Sea at the north, the Marmara sea andAegean sea to the west and the Mediterranean sea to the south. The average rainfallnationwide is about 650 mm, but this average masks large variations, from about250 mm in the central and Southeastern plateaus to as high as 2 500 mm in theNortheastern coastal plains and mountains. In the western and southern coastal zones,a subtropical Mediterranean climate predominates, with short, mild and wet wintersand long, hot, and dry summers. Arid and semi-arid continental climates prevail incentral regions where winter conditions are often extremely harsh, with frequent andheavy snowfall in the higher parts of the Anatolian Plain. On the Black Sea coast,winters are very wet and summers mild and humid. The average annual temperaturevaries between 18 to 20°C on the south coast, drops to 14 to 16°C on the west coast,and in central parts fluctuates between 4 to 18°C. Local micro-climates can varywidely from the regional averages because of the highly variable terrain and exposureto hot and cold winds [4].

Although Turkey has almost all kinds of energy resources, it is an energyimporting country, since these resources are limited. More than half of the primaryenergy consumption in the country is met by imports and the share of imports con-


tinues to increase each year. Therefore, it seems that if the country wants to supplyits demand by domestic resources (such as lignite, hard coal, oil and natural gas) torenewable energy resources must be realised in a reasonable time period [5].

The total renewable energy production and consumption of Turkey are equal toeach other, varying between 9.3–10.8 million toe each for the 1988–1998 period(Table 1). Their share in total energy production varies average between 37–43%while in total consumption between 15–22% for the same period. Among the pro-duction of renewables, biomass that includes wood and dung, is the highest in 1988,reaching 7.8 million toe. The second highest is hydroelectric production whichreached 3.5 million toe in 1998. The production of geothermal and solar energy isnegligible compared with to biomass and hydroelectric power, varying from 71 to354 thousand toe between 1988 and 1998 (see Table 1). On the other hand, Turkey’sfirst wind farm was commissioned in 1998, and has a capacity of 1.5 MW. Capacityis likely to grow rapidly, as plans have been submitted for just under a further 600MW of independent facilities of which 57 MW is at an advanced stage in negoti-ations. The majority of proposed projects are located in the Cesme (Izmir) andCanakkale [5].

2. A brief look at the energy sector of Turkey

The energy demand of Turkey will be doubled between the years 2000–2010 andwill be fivefold between 2000–2025. This rapid increase in demand is due to thehigh economic development rate of Turkey. The estimated amount of investmentsfor the production facilities by the year 2010 is around 45 billion dollars. Trans-mission and distribution facilities will require an additional 10 billion dollar invest-ment in the same period. The government has undertaken measures to attract localand foreign private sector for new investments, and also to transfer operational rightsof existing units to the private sector for their renewal and efficient operation [5,6].

Turkey is an energy importing country; more than half of the energy requirementhas been supplied by imports. Oil has the biggest share in total primary energyconsumption. Due to the diversification efforts of energy sources use of natural gas,that was newly introduced into the Turkish economy, has been growing rapidly.Turkey has large reserves of coal, particularly of lignite. The proven lignite reservesare 8.0 billion tons. The estimated total possible reserves are 30 billion tons. Amajority of the lignites, mostly situated in Afsin-Elbistan, Soma and Tuncbilek, arecharacterized with high ash contents in the range of 14 to 42%, high moisture con-tents ranging from 15 to 50% and volatile matter contents of 16–38% [5].

Important developments have been recorded in primary energy and electricity con-sumption during the last forty years. In this period, primary energy consumption hasincreased by an average of 5.0 percent and electricity consumption by 10 percent,annually. Despite high growth rates, primary energy and electricity consumption arequite below the levels of OECD countries.

In 1998, primary energy production and consumption has reached 29 and 74million tons of oil equivalent (mtoe) respectively in 1998 (Table 1). The most sig-


Tab

le1

Prim

ary

ener

gyco

nsum

ptio

nof

Tur

key

duri

ng19

88–1

998

(kto

e)a

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

Non

-Ren

ewab

leH

ard

coal

5230

4725

6491

6844

6803

6671

6428

6690

9115

8495

8160

Lig

nite

7932

1020

797

6510

572

1074

399

1810

331

1060

511

187

1228

012

414

Oil

2259

022

865

2390

123

315

2486

528

412

2714

229

324

3093

930

515

3208

3N

atur

alga

s11

1528

7831

1038

2741

9746

3049

2163

1373

8491

6510

635

Tot

alfo

ssil

3686

740

675

4326

744

558

4660

849

631

4882

252

932

5862

560

455

6329

2R

enew

able

Hyd

ropo

wer

2490

1543

1991

1951

2285

2920

2630

3057

3481

3424

3520

Geo

ther

mal

5859

8586

9097

115

138

162

179

256

Sola

r13

1621

2732

3845

5280

8098

Woo

d53

1353

4553

6153

9154

2154

5154

8255

1255

1255

1255

12W

aste

and

Dun

g25

2725

0418

4718

2117

8816

9716

2715

5615

3315

1214

92T

otal

rene

wab

le10

401

9467

9305

9276

9616

1020

398

9910

315

1076

810

707

1087

8T

otal

cons

umpt

ion

4726

850

142

5257

253

834

5622

459

834

5872

163

247

6939

371

162

7417

0T

otal

prod

ucti

on24

267

2541

425

123

2513

826

408

2602

126

059

2625

526

926

2768

728

784

aSo

urce

:[6

].


nificant developments in production are observed in hydraulic energy and oil pro-duction. Oil production reached 4.5 million tons in 1991, the highest level in itshistory. Thus, the share of indigenous oil in the total oil supply rose to 20 percent.However, this development could not be maintained in the following years, andproduction of oil has entered into a regression period.

As of the end of 1998, installed capacity and generation capacity of power plantsreached 20 952 MW and 86 247 GW, respectively. As of 1998, electricity demandwhich amounts to 78 billion kWh was met continuously with a high reserve margin.However, it is crucial to ensure the continuity of investments in order to meet elec-tricity demand continuously and safely in the coming years, and which is increas-ing rapidly.

The findings of the Ministry of Energy and Natural Resources suggest that theprimary energy demand will be equivalent to 91 030 kilo tonnes of oil equivalent(ktoe) in the year 2000, and 314 353 ktoe in 2020 in Turkey. In line with this trend,in 2023 marking the centennial of the country, the primary energy consumption willreach 367 780 ktoe and 407 106 ktoe two years later in 2025. According to theMinistry’s production forecasts, domestic production of primary energy will level31 091 ktoe in 2000 and 79 399 ktoe by 2020. The projections foresee domesticgeneration to top 91 408 ktoe in 2023 and 95 946 ktoe in 2025. Table 2 gives thefindings related to primary energy resources and their domestic production planning.

3. Renewable energy use and economics

Hydroelectric generation, biomass combustion, solar energy for agricultural graindrying and hot water heating, and geothermal energy have been in use in the countryfor many years. Domestic water heating is the prime area for active solar systems.In Turkey, approximately 30 000 solar water heating systems have been installedsince the 1980s. This is a minute fraction of the total potential. It is likely that around50% of existing dwellings could be suitable to have a solar water heater fitted. Ifthis potential were to be taken up by 2025, this would require the deployment ofapproximately 5 million systems (allowing for a rise in the Turkish housing stock).This could save an estimated 30 PJ (9.0 TWh) per year of oil, coal and gas and 2.0TWh per year of electricity, giving a saving of 5.0 million tonnes of CO2 per year,or just under 1% of current Turkey CO2 production.

The cost of solar energy collecting systems differ depending upon the type ofmaterial used for the case of collectors, absorbent plate and water storage tank. Atypical solar energy collecting system used for water heating contains two collectors(total 4–6 m2 surface area) and a 160–200 litre capacity water storage tank, such asystem typically costs approximately $1000 which is accounted for by the installer’soverheads and marketing costs. In 1997, some 3500 domestic solar heating systemswere sold in Turkey. Solar energy collecting systems have an initial cost two to fivetimes higher than alternatives using electricity, LPG, fuel or other solid energysources. However, their annual repair and maintenance costs are much lower thanalternatives due to high energy prices. Solar systems with inflated annual costs have


Tab

le2

Prim

ary

ener

gypr

oduc

tion

and

cons

umpt

ion

(in

pare

nthe

sis)

targ

ets

ofT

urke

ybe

twee

n20

00–2

035

(kto

e)a

Ene

rgy

Sour

ces

2000

2005

2010

2015

2020

2023

2025

Coa

l(h

.coa

l+lig

nite

)17

202

2125

928

522

3182

039

385

4273

245

944

(20

256)

(30

474)

(50

311)

(83

258)

(129

106)

(198

798)

(296

997)

Oil

&N

atur

alga

s34

0821

2717

3515

1616

0415

0514

55(5

925

0)(7

325

6)(9

263

7)(1

1299

3)(1

3636

5)(1

5846

7)(1

7976

5)C

entr

alhe

atin

g25

349

588

413

3620

1824

2727

48(2

53)

(495

)(8

84)

(133

6)(2

018)

(245

7)(2

748)

Hyd

ropo

wer

3763

5845

7520

8873

9454

1000

210

445

(376

3)(5

845)

(752

0)(8

873)

(945

4)(1

000

2)(1

044

5)W

ood

&W

aste

6963

6760

6446

6029

5681

5498

5393

(696

3)(6

760)

(644

6)(6

029)

(568

1)(5

498)

(539

3)G

eoth

erm

al43

213

8037

6048

6048

6054

0054

00(4

32)

(138

0)(3

760)

(486

0)(4

860)

(540

0)(5

400)

Nuc

lear

0.0

0.0

3657

9143

1828

626

988

2920

0(0

.0)

(0.0

)(3

657)

(914

3)(1

8286

)(2

6988

)(2

9200

)So

lar

204

459

907

1508

2294

2845

3248

(204

(459

)(9

07)

(150

8)(2

294)

(284

5)(3

248)

Win

d55

250

620

980

1440

1786

2134

(55)

(250

)(6

20)

(980

)(1

440)

(178

6)(2

134)

aSo

urce

:[6

].


a minimum present value of $866. A detailed technical–economic analysis has beenperformed for solar and biogas space heating systems by several researchers that aregiven in the literature [7,8]. The results provide evidence of the economic viabilityof biogas systems over the traditional space heating systems of rural Turkey inmany instances.

Unlike many of the other renewables, hydroelectricity is a very well-establishedtechnology. The water-control systems and the turbo-generators to extract the powerare standard items. The many existing installations cover a power range from hun-dreds of watts to thousands of megawatts. Nevertheless, despite all the availabledata, it is very difficult to calculate the cost of hydroelectric power. The reason liesin the combination of heavy front-end loading and extremely site-specific construc-tion costs. In other words, the dominant factor in determining the total cost per unitof output is the initial capital cost, and a major part of this can be the civil engineeringcosts which vary greatly from region to region in Turkey.

A detailed energy and economic comparison of air-to-air heat pumps and conven-tional heating systems for the Turkish climate has been performed by Kaygusuz [9].This study showed that the heat pump offers economic advantages over the oil andcoal-fired boiler systems, but is not an economic alternative to the gas-fired heatingsystem. Because the unit price of the gas is 3.8 times less than that for electricityin Turkey, to become competitive with a gas-fired boiler, either the capital cost ofthe heat pump must be substantially reduced or its seasonal COP increased by about60%; it should also be driven by a gas engine rather than an electric engine. Table3 gives the annualised life-cycle cost of heating systems results obtained in fourdifferent climatic regions in Turkey.

Wood for fuel from forest energy and energy forestry has the potential to makea significant contribution to the future energy mix. At present, forests still providethe major part of energy supplies for cooking and heating in rural areas, and forestryoperations are the most important source of employment for the 9 million forestvillagers. There are nearly 8,000 sawmills in Turkey as well as over 50 chipboard,plywood and fibreboard plants, most of which operate at well under their installedcapacities. Raw materials are now inadequate for domestic demand and around 2.5million cubic metres of industrial wood are imported annually [4].

Table 3Annualised life-cycle cost of heating systems

Annual fuel Annualised life-cycle cost ($)price escalationrate (%) Ankara Antalya Trabzon Kars

Heat pump 12 384.7 318.1 350.4 485.8Electrical heater 12 314.2 147.7 229.4 573.6Gas-fired boiler 12 264.6 222.7 246.3 345.7Oil-fired boiler 12 448.8 400.0 426.6 542.7Coal-fired boiler 12 466.5 390.2 430.9 603.1


4. Hydroelectricity

Hydroelectricity is well established as one of the principal energy-producing tech-nologies around the world, providing some 20% of the world’s electricity. In thedeveloping countries, the proportion rises to around 40%. The capacity of largehydroelectric schemes can be several times that of a conventional power station.They are highly efficient, reliable, and long lasting. They are also very controllableand add an element of storage into an electricity supply system, thereby allowingcompensation for the varying intensity of other renewable energy sources and forvariations in electricity demand. However, the dams and their large lakes forms alsohave major environmental and social impacts [3].

There are 436 sites available for hydroelectric plant construction, distributed on26 main river zones. Table 4 gives water and hydroelectric energy potential of selec-ted river basins in Turkey. The total gross potential and total energy productioncapacity of these sites are nearly 50 GW and 112 TWh/yr, respectively. As an aver-age 30% of the total gross potential may be economically exploitable. At present,only about 18% of the total hydroelectric power potential is exploited. The nationaldevelopment plan aims to harvest all of the hydroelectric potential by 2010. Thecontribution of small hydroelectric plants to total electricity generation is estimatedto be 5–10% [10].

The Southeastern Anatolia Project (GAP) is one of the largest power generating,irrigation, and development projects of its kind in the world, covering 3 million haof agricultural land. This is over 10% of the cultivable land in Turkey; the land tobe irrigated is more than half of the presently irrigated area in Turkey. The GAPproject on the Euphrates and Tygrys Rivers encompasses 22 dams and 19 hydroelec-tric power plants. Once completed, 27 billion kWh of electricity will be generatedand irrigating 1.7 million hectares.

The Ataturk Dam which the sixth largest-volume dam (48.7 billion m3) in theworld is installed in Urfa province by the DSI. The type of dam is rock packed, 169m high from the river bed and 1664 m along the crest. Body packed volume of thedam is 84.5 million m3. The Ataturk Dam has eight units with 300 MW installedcapacity of each unit and mean value of electrical energy production is 8.5 billionkWh/year.

The anlyurfa Irrigation Tunnel system is the largest of its kind, with numerousirrigation networks and canal systems constituting the physical groundwork in waterresources. The tunnel system contains two parallel tunnels each 26.4 km long. Theinner diameter of each tunnel is 7.62 m the and area irrigated by the two tunnels is476 000 hectares [10–12].

5. Biomass

Biomass energy includes fuelwood, agricultural residues, animal wastes, charcoal,and other fuels derived from biological sources and is used by approximately halfof the world’s population as cooking and/or heating fuel, and it currently accounts


Tab

le4

Wat

eran

den

ergy

pote

ntia

lof

sele

cted

rive

rba

sins

inT

urke

ya

Nam

eof

basi

nL

and

area

(km

2)

Ave

rage

rain

fall

Num

ber

ofda

mSt

ored

wat

er(h

m3)

Inst

alle

dca

paci

tyA

vera

gege

nera

tion

(mm

/yr.

)(M

W)

(GW

h)

Susu

rluk

2239

971

1.6

2535

09.3

537.

016

97G

ediz

1800

060

3.0

1433

69.4

250.

042

5B

.M

ende

res

2497

666

4.3

1927

22.1

214.

584

8B

.A

kden

iz20

953

875.

824

1836

.667

4.7

2495

Ant

alya

1957

710

00.4

1528

85.3

1251

.644

11Sa

kary

a58

160

524.

745

6920

.310

62.5

2362

B.

Kar

aden

iz29

598

811.

024

2518

.859

2.7

2110

Yep

ilyrm

ak36

114

496.

545

6301

.816

57.6

6468

Kyz

ylyr

mak

7818

044

6.1

8221

260.

020

07.0

6512

D.

Akd

eniz

2204

874

5.0

1191

21.5

1495

.951

76Se

yhan

2045

062

4.0

1861

24.5

1885

.671

17C

eyha

n21

982

731.

625

7719

.514

08.7

4634

Fyra

t12

730

454

0.1

8311

279

1.5

9844

.838

939

D.

Kar

aden

iz24

077

1198

.243

1522

.533

23.1

1092

7C

oruh

1987

262

9.4

2075

44.4

3227

.410

614

Ara

s27

548

432.

420

4084

.858

5.2

2291

Dic

le57

614

807.

236

3029

5.0

5081

.916

876

Tot

alT

urke

y77

945

264

2.6

702

240

763.

635

309.

212

456

8

aSo

urce

:[1

1].


Table 5Total and recoverable bioenergy potential of animal wastes in Turkey (1998)

Kind of animal Total number of Coefficient of Total energy Recoverableanimalsa conversion potential (ktoe) energy potential(thousand (ktoe per (ktoe)heads) thousand

animals)

Sheep and goats 75 095 0.048 3604 1081Donkey, horse, mule and camel 1370 0.235 322 97Poultry 311 500 0.003 935 281Cattle and buffalo 12 121 0.245 2970 891

a Data obtained from [4].

for about 14% of world energy consumption. Biomass is the main source of energyfor many developing countries, providing more than 90% of the energy supply insome developing countries. Fuelwood and other biomass fuels are handled and com-busted primarily by women, who are largely responsible for reproductive chores suchas cooking and are often involved in many household industries. Women and childrengenerally have the main responsibility for collecting fuel [13,14].

Among the renewable energy sources, biomass is important because its share oftotal energy consumption is still high. Since 1980, the contribution of the biomassresources in the total energy consumption dropped from 20 to 10% in 1998. Biomassin the forms of fuelwood and animal wastes is the main fuel for heating and cookingin many urban areas. The total recoverable bioenergy potential is estimated to beabout 16.92 Mtoe. The estimate is based on the recoverable energy potential fromthe main agricultural residues, livestock farming wastes, forestry and wood pro-cessing residues and municipal wastes, given in the literature [15]. Table 5 givestotal and recoverable bioenergy potential of animal wastes and Table 6 gives totalrecoverable bioenergy potential in Turkey.

Table 6Total recoverable bioenergy potential in Turkey (1998)

Type of biomass Energy potential (ktoe)

Dry agricultural residue 4560Moist agricultural residue 250Animal waste 2350Forestry & wood processing residues 4300Municipality wastes & human extra 1300Firewood 4160Total bioenergy 16 920


6. Geothermal energy

Turkey is one of the countries with significant potential in geothermal energy.Data accumulated since 1962 show that there may exist about 4500 MW of geother-mal energy usable for electrical power generation in high enthalpy zones. Heatingcapacity in the country runs at 350 MWt equivalent to 50 000 households. Thesenumbers can be heightened some sevenfold to 2 250 MWt equal to 350 000 house-holds through a proven and exhaustible potential. Turkey must target 1.3 millionhouse holds equivalent 7 700 MWt. Geothermal central heating, which is less costlythan natural gas could be feasible for many regions in the country. In addition 31 000MW of geothermal energy potential is estimated for direct use in thermal appli-cations. The total geothermal energy potential of Turkey is about 2 268 MW in 1998,but the share of geothermal energy production, both for electrical and thermal usesis only 1 200 MW. There are 26 geothermal district heating systems exist now inTurkey. Main city geothermal district heating systems are in Gonen, Simav andKyr ehir cities [5].

6.1. Geothermal heat pumps

Heat pumps stand out because they are able to convert low-grade heat into usefulheat. Even in winter, the outside air, water and ground still contain heat which canbe extracted and upgraded by a heat pump. This natural heat can be used to heatbuildings or for hot water production. The heat sources are continually replenishedby the sun, therefore the extracted heat is renewable energy. Heat pumps can alsoextract waste heat, e.g. from ventilation air, and make it suitable for reuse. Theenergy needed to drive a heat pump is only about one third or less of the usefulheat produced.

Geothermal heat pumps are a relatively new application of geothermal energy thathas grown rapidly in recent years. They use Earth as a heat sink in the summer anda heat source in the winter, and therefore rely on the relative warmth of the earthfor their heating and cooling production. On the other hand, the biggest benefit ofgeothermal heat pumps is that they use 25–50% less electricity than conventionalheating or cooling systems. Geothermal heat pumps can also reduce energy consump-tion — and corresponding air pollution emissions — up to 44% compared to airsource heat pumps and up to 72% compared to electric resistance heating with stan-dard air-conditioning equipment [16].

Detailed technical and economic analyses have been performed for geothermalheat pump district heating systems for Turkey by several researchers and are givenin the literature [17–19]. These studies shows that there is a good potential for geo-thermal heat pump heating and refrigeration application in the country. A study con-ducted by Kilkis and Eltez [19] shows that the useful energy extracted from a givengeothermal reservoir in a district can be increased by 70% through a hybrid/integratedsystem, when compared to a simple open-loop system. Coupled with the properdemand side management design, it is projected that about 115% more customerscan be serviced with the same amount of geofluid extracted, without thermal peaking.


This also shows that when district heating and cooling is involved in a geothermalsystem heat pumps and hybrid HVAC systems seem to play the key roles.

7. Solar energy

Solar radiation can be converted into useful energy directly, using various techno-logies. It can be absorbed in solar collectors to provide solar space or water heatingat relatively low temperatures. Buildings can be designed with passive solar featuresthat allow solar energy to contribute to their space heating requirements. Small solarcollectors are widely used to supply domestic hot water in several countries, includ-ing Japan, Turkey, Australia, Greece, UK, USA, Canada and Israel. It can be concen-trated by parabolic mirrors to provide heat at up to several thousand degrees Celcius,and these high temperatures may then be used either for heating purposes or togenerate electricity. Solar radiation can also be converted directly into electricalenergy using photovoltaic solar cells [3].

Turkey lies in a sunny belt between 36° and 42°N latitudes. The yearly averagesolar radiation is 3.6 kWh/m2-day and the total yearly radiation period is approxi-mately 2640 hours, (Table 7) which is sufficient to provide adequate energy for solarthermal applications. In spite of this high potential, solar energy technologies arenot now widely used, except for flat-plate solar collectors. They are only used fordomestic hot water production, mostly in the sunny coastal regions. In 1998, about3.0 million m2 solar collectors were produced and it is predicted that total solarenergy production is about 0.080 million ton of oil equivalent (Mtoe) [5]. The globalsolar radiation incident on a horizontal surface and daily sunshine hours are measuredby all recording stations in Turkey. Solar radiation calculations have been performedby several researchers for Turkey that are given in the literature [20–23].

Table 7Solar and wind energy potential by regions of Turkeya

Annual average Annual average Annual average Sunshinewind density wind speed solar radiation duration(W/m2) (m/s) (kWh/m2-yr) (hour/yr)

Marmara 51.91 3.29 1168 2409Southeast Anatolia 29.33 2.69 1460 2993Aegean 23.47 2.65 1304 2738Mediterranean 21.36 2.45 1390 2956Black Sea 21.31 2.38 1120 1971Central Anatolia 20.14 2.46 1314 2628East Anatolia 13.19 2.12 1365 2664Turkey Average 25.81 2.57 1303 2623

a Source: [5].


7.1. Solar heat pump combination

The largest number of heat pumps currently being used are small reversible unitswhich can provide both heating and cooling, in individual rooms, houses, shops,offices, schools and institutional buildings. Annually, over 10 million units are pro-duced worldwide, and over 65 million units are in operation in Japan, the USA,China and Europe. These heat pumps are cost effective in many regions of the world,as they cost little extra compared to a cooling-only air conditioner. On the otherhand, in cold to moderate climates, heating-only heat pumps are used to heat tapwater and homes. In commercial buildings and industrial processes, heat pumps areoften applied where simultaneous heating and cooling is required, or heating in win-ter and cooling in summer. World wide over 10 million systems are installed incommercial and institutional buildings [24].

A detailed experimental and theoretical study has been performed for solar heatpump combination for domestic heating by Kaygusuz [25–29] for Trabzon, Turkey.Solar energy and heat pump systems are two promising means of reducing the con-sumption of fossil-fuel resources, and hopefully, the cost of delivered energy forresidential heating. An intelligent extension of each is to try to combine the two inorder to further reduce the cost of delivered energy. Solar heat-pump systems canbe classified according to the source of heat that supplies the evaporator of the heatpump as either parallel, series or dual. In parallel systems, the heat pump receivesenergy from the outdoor air, and the collected solar energy is supplied directly foreither space heating or for heating water. In the series system, solar energy is suppliedto the evaporator of the heat pump, thereby raising its temperature and increasingthe coefficient of performance (COP). In the dual source configuration, the evaporatoris designed so that it can receive energy from either the outdoor air or from thesolar-energy store. Our studies show that there is a great potential for using solarheat pump combinations for domestic heating/cooling applications in Turkey. Table8 gives the theoretical results of air-to-air heat pump systems obtained from differentlocations in Turkey. Table 9 gives the theoretical results of solar-assisted series heatpump systems for domestic heating obtained in Trabzon, Turkey. The calculationmethods of the solar-assisted series heat pump heating system are given in the litera-ture [25–29].

7.2. Photovoltaic energy

Turkey currently does not have an organized photovoltaic (PV) program. Globalenergy strategies and policies are laid down in periodic five-year development plans.The Government has no intention of PV production. On the other hand, it is encour-aged to invest in the energy sector by some financial incentives. Plans for industrialscale production of PV modules are concentrated in thin film areas rather than crys-talline materials. PV cells are produced in various research establishments in orderto study the feasibility of local manufacturing. So far none of these studies hasyielded a positive result in order to justify a mass production facility in Turkey. Thepotential of Turkey as a PV market is very large, since the country is very suitable


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Table 9The theoretical results of the solar-assisted series heat pump system during the heating season in Trabzona

Month Q Ta RH I I0 ID N COP hcol hst f(kW) (°C) (%)

November 1915 12.0 76.2 5.60 13.40 2.56 19 4.50 0.63 0.62 0.66December 3160 8.4 68.4 4.12 12.38 2.20 15 4.30 0.55 0.58 0.55January 4376 4.6 66.7 5.42 14.66 2.30 18 4.20 0.50 0.60 0.65February 4360 3.2 67.3 6.26 20.22 3.39 22 4.10 0.58 0.64 0.70March 3012 8.6 65.3 7.35 22.92 4.67 18 4.20 0.60 0.62 0.72April 2210 11.3 72.1 11.60 35.74 6.16 20 4.50 0.59 0.64 0.74

a All values are averages taken over a month.

in terms of insolation and large areas of available land for solar farms. There aremore than 30 000 small residential areas where solar powered electricity would likelybe more economical than grid supply. Another potential for the PV market is holidayvillages at the long coastal areas. These facilities are frequently far from the maingrid nodes and require additional power when solar insolation is high. Unfortunatelyenergy demand in Turkey is so large that utilities are concentrating on large conven-tional power plants and peak load facilities. The newest five years development plan,being prepared, foresees a more ambitious program and estimates approximately 40MWp installed power by the year 2010 [5,30].

8. Wind energy

More than 20 000 wind turbines are in use around the world for generating elec-tricity, and over a million for pumping water. Although experimental wind turbinesup to several megawatts in size have been built, the optimum size currently appearsto be around 300–500 kilowatts. There are many areas in which wind energy isplentiful. In Europe it has been estimated that as much as 25% of its current elec-tricity demand could be met from wind energy sources once technical and environ-mental constraints have been taken into account [3].

There are a number of regions in Turkey with relatively high wind speeds (seeTable 7). These have been classified into six wind regions, with a low of about 3.5m/s and a high of 5 m/s at 10 m altitude, corresponding to a theoretical powerproduction between 1000 and 3000 kWh/(m2.yr) The most attractive sites are theMarmara Sea region, Mediterranean Coast, Aegean Sea Coast, and Anatolia inland[31–33]. Turkey’s first wind farm was commissioned in 1998, and has a capacity of1.5 MW. Capacity is likely to grow rapidly, as plans have been submitted for justunder a further 600 MW of independent facilities. The majority of proposed projectsare located in the Cesme, Izmir and Canakkale regions. Electrical power resourcessurvey and development administration (EIE) carries out wind measurements at vari-ous locations to evaluate wind energy potential over the country, and has started tocompile a wind energy atlas (in cooperation with other organisations). Approval


of independent wind energy projects requires at least a six month history of windmeasurements. Table 2 shows primary energy production and consumption targetsof Turkey. As shown in Table 2, the use of geothermal, wind and solar energy willincrease between the years 2000–2025. For example, in year 2025, 25 per cent ofthe total production will be provided by renewables (hydro, geothermal, wind, solar,wood and waste).

9. Sustainable development

A secure supply of energy resources is generally agreed to be a necessary but notsufficient requirement for development within a society. Furthermore, sustainabledevelopment demands a sustainable supply of energy resources. The implications ofthese statements are numerous, and depend on how sustainable is defined. Oneimportant implication of these statements is that sustainable development within asociety requires a supply of energy resources that, in the long term, is readily andsustainably available at reasonable cost and can be utilized for all required taskswithout causing negative societal impacts. Supplies of such energy resources as fossilfuels (coal, oil, natural gas) and nuclear fuels (uranium and thorium) are generallyacknowledged to be finite; other energy sources such as solar, hydropower, biomassand wind are generally considered renewable and therefore sustainable over the rela-tively long term [34].

The world’s proven reserves of oil have increased from some 540 billion barrelsin 1969 to just over 1000 billion barrels in 1992, but this is not to say that potentialreserves are unlimited. The earth has been surveyed in great detail by the oil compa-nies, and the easiest, cheapest and most promising reservoirs have all been found.Except for the huge pool of oil in the Middle East, the world’s most readily exploit-able sources of oil and gas have been used up. It is only because of this that suchdifficult sources of oil as the North Sea and Alaska have become economicallyviable: that is, the price of oil has risen enough to make them worth exploiting. Onthe other hand, in the case of natural gas, the situation is somewhat different, becauseof the massive reserves in the former Soviet Union. This region holds some 40% ofthe world’s gas reserves, and another 40% of gas is in the OPEC region. In contrast,the world’s coal reserves are much larger and much more evenly distributed. In 1992the world reserve/production ratio for coal was over 200 years. Unfortunately, coalhas disadvantages compared to oil and gas as it produces more CO2 per unit ofenergy released than is the case with gas and oil, and more SO2 and NOx [3].

Fossil fuel reserves, production rates in 1998, and estimated sustainability yearsare given in Table 10. Turkey does not possess ample fossil fuel reserves. Excludinglignite, coal, oil and natural gas reserves in the country are quite scant and are farfrom meeting the domestic demand. In a longer perspective, lignite deposits do notseem to be sufficient either. Turkey’s total extractable reserves of coal, oil, naturalgas, asphaltite and bitumen amount 2454 Mtoe. All bitumen and thorium (Table 10).The average growth rates of the periods during which production rates have beenstably increasing are included in the estimation of sustainability years. Technically


Table 10Fossil fuel reserves, production rates in 1998, and sustainability years

Fuel Reserves (Mton) Production in Sustainability1998 (kton/yr) years

Recoverable Total possible

Coal 170 1,126 1,380 55a

Lignite 7,120 8,130 12 909 105b

Petroleum 130 130 3,385 30c

Natural gas (106 m3) 20 20 565 24d

Asphalts 40 75 23 120Bitumens 830 1,490 – –Uranium (kton) 9,2 9,2 – –Thorium (kton) – 380 – –

a Future production as that of 1998, based on the last 15 yrs.b With 0.005% increase in future production, based on the last 10 yrs.c With 0.004% increase in future production, based on the last 15 yrs.d With 0.09% increase in future production, based on the last 10 yrs.

and economically recoverable reserves are also included in the estimation by usingyearly energy statistics of Turkey. The results for each fossil fuel are given in Table10. As shown, unless new fossil-fuel deposits are discovered or the possible reservesbecome feasibly extractable, indigenous fossil fuels have very limited lifetimes.

Power has become an essential part of our everyday lifestyles. The liability fallson everyone who consumes energy. The economy and the desire to improve ouratmosphere and ecosystem demand that we be wise when making decisions. Thisreasoning must be practised by everyone, from the power companies on down toeach individual consumer. The utility companies must search out and utilise everytechnology and system update that will increase its efficiency. The consumer mustdo the same and not be wasteful in energy use. In addition, supply-side managementtechniques generally seem to benefit the individual using the system or technology.Solar collectors, geothermal and wind turbines, biogas, and heat pumps are all goodideas, but individuals (or companies) must be systematic in analysing their needsand in choosing the correct system that will best aid them in achieving the desiredpurposes. On the other hand, the environmental concerns are an important factor insustainable development. For a variety of reasons, activities which continuallydegrade the environment are not sustainable over time. A large portion of theenvironmental impact in a society is associated with its utilisation of energyresources. Therefore, improved energy efficiency in power plants and energy usingmachines leads to reduced energy losses and less environmental pollution [35].

10. Air pollution in Turkey

Air pollution is becoming a great environmental concern in Turkey. Air pollutionfrom energy utilization in the country is due to the combustion of coal, lignite,


petroleum, asphaltite, natural gas, wood and agricultural and animal wastes. In Tur-key the amount of CO2 emissions was about 73 million tons in 1998. The amountof carbon emission per person was about 1020 kg, and per square kilometer was105 tons. The total amount of carbon emissions will increase to 83–93 million tonsin the year 2000 and to 128–166 million tons in 2010, according to the probableportion approach method [5,36]. On the other hand, the amount of carbon emissionsis less by 14–16% with the economic sensitivity approach method, which gives theseamounts as 77–86 million tons in 2000 and 110–140 million tons in 2010 (Table 11).

Owing mainly to the rapid growth of primary energy consumption and the increas-ing use of domestic lignite, SO2 emissions in particular have increased rapidly inrecent years in Turkey. According to the estimates given by the Ministry of Energy,total SO2 emissions in Turkey were about 2100 million tons in 1998. The majorsource of SO2 emissions is the power sector, contributing more than 50% of the totalemissions. As given in the literature [36,37], SO2 concentrations in the flue gas ofsome lignite-fired power stations are extremely high and differ notably betweenpower plants, owing to the variation of the sulphur content of the fuels. Table 12gives the amount of SO2 emissions from combustion sources in 1998, 2000, and2010 for Turkey.

Although the NO2 emissions are lower than SO2 emissions in Turkey, they havelikewise increased rapidly, following the growth of energy requirements. Contraryto the development of SO2 emissions, a similar upward trend of NO2 emissions hasbeen observed in many European Community countries as well, resulting mainlyfrom the increased traffic density. Also in Turkey, nearly 50% of the total NO2

emissions are from the transportation sector, while less than 20% are caused bypower generation. Per capita NO2 emissions are still much lower in Turkey than inthe European Community countries, i.e., less than one-third of these countries’ aver-age. Table 13 gives the amount of NO2 emissions in 1998, 200O and 2010 forTurkey [5,36,37].

Table 11Predicted emissions of carbon from combustion sources in Turkey

2000 2010

1998 Low Normal High Low Normal High

Emission (million tons)Possible portion 78.6 83.4 88.2 92.7 128.2 145.9 165.7Economical portion 72.7 77.5 81.6 85.8 109.5 123.1 139.4

Emission (ton/km2)Possible portion 102.2 107 113 119 164 187 212Economic portion 94.2 99 105 110 140 158 179

Emission (kg/person)Possible portion 1102 1202 1271 1336 1543 1755 1994Economic portion 1017 1117 1176 1236 1318 1482 1677


Table 12Predicted emissions of SO2 from combustion sources in Turkey

2000 2010


Emission (thousand tons)Possible portion 2235 2337 2492 2641 2356 2737 3163Economical portion 2064 2165 2303 2439 1977 2265 2609

Emission (ton/km2)Possible portion 2.2 3.0 3.2 3.4 3.0 3.5 4.1Economic portion 1.9 2.8 3.0 3.1 2.5 2.9 3.3

Emission (kg/person)Possible portion 32.4 33.7 35.9 38.1 28.4 32.9 38.1Economic portion 30.2 31.2 33.2 35.1 23.8 27.3 31.4

Table 13Predicted emissions of NO2 from combustion sources in Turkey

2000 2010


Emission (thousand tons)Possible portion 1219 1319 1389 1461 2027 2280 2565Economical portion 1117 1217 1278 1343 1746 1950 2187

Emission (ton/km2)Possible portion 1.3 1.7 1.8 1.9 2.6 2.9 3.3Economic portion 1.2 1.6 1.6 1.7 2.2 2.5 2.8

Emission (kg/person)Possible portion 17.4 19.0 20.0 21.1 24.4 27.4 30.9Economic portion 15.3 17.5 18.4 19.4 21.0 23.5 26.3

11. Conclusions

The promise of renewable energy is that it offers a solution to many of the environ-mental and social problems associated with fossil and nuclear fuels. Whilst it appearsto be technically possible to replace all fossil and nuclear fuels with renewable energysources, on the basis of present and projected costs the energy supplied would besubstantially more expensive than it is now. However, there is a strong argumentthat conventional fuels are currently underpriced because their prices do not includeprovision for their environmental effects.

On the other hand, The CO2 emissions reduction potential of 6% will increase inthe near future, because both heat pumps and power plants are becoming moreefficient as a result of technology developments. While the efficiency of a fossil-fuelled boiler based on the higher heating value can never be higher than 100%, thetheoretical attainable heat output of a space heating heat pump is about 14 times the


energy input by electricity, in other words, the theoretical COP is 14. Today’s actualCOPs range from 2.5 to 4 with a few installations reaching 7, but further improve-ments are envisaged, increasing the emissions saving by heat pumps. An actual COPof 8 is anticipated within the next decade. Consequently heat pumps will becomemore attractive and take a larger share of the heating market [24].

Renewable energy resources and their utilisation in Turkey are intimately relatedto sustainable development. For the governments or societies to attain sustainabledevelopment, much effort should be devoted to utilising sustainable energy resourcesin terms of renewables. In addition, environmental concerns should be addressed.The following concluding remarks can be drawn from this study:

� There are a number of environmental problems in the country that we face today.These problems span a continuously growing range of pollutants, hazards andecosystem degradation over the country.

� All government agencies and non-governmental agencies in the country mustwork together to utilise their renewable energy and choose the appropriate appli-cation for Turkey.

� Development of advanced renewable energy technologies that serve as cost-effec-tive and environmentally friendly alternatives to conventional energy generationsystems. So, the governmental energy institutions and special sector agenciesshould recognise this opportunity.

� Wind energy presents a considerable opportunity for our country to obtain a sig-nificant part of our future energy needs from this sustainable source.

� Further develop projects aiming at sustainable management of natural resourcesand income generation in rural areas of the country that ensure the environmentalimpact assessment of sub-projects of the GAP, and minimise their adverseenvironmental impacts (e.g. erosion).

� Sustainable development demands a sustainable supply of energy resources that, inthe long term, is readily and sustainably available at reasonable cost in the country.

� Increasing Turkey’s population requires the definition and successful implemen-tation of sustainable development in the country.

� Sustainable development could only be achieved by provision of high quality,environmentally responsible energy on time, at a reasonable price.

� Utilisation of heat pumps in industrial and domestic heating sectors should becomewidespread in the country through the financial support of the Turkish govern-ment.

� In order to reduce CO2, SO2, and NO2 emissions from fossil fuels, energy utilityowners and sectors should increase energy savings and efficiency in all powerplants and fuel consuming engines and machines. In power plants, cogenerationsystems should be used.

� It was claimed that the Built Operate Transfer Model has been the best modelfor hydroelectric and geothermal energy investments, within the framework ofcurrent legal documents.

� Studies for exploration of new coal fields should continue to sustainable develop-ment in the energy sector. Special importance should be given for the use of most


proper burning technologies for Turkish lignites, to obtain a clean environmentfor the future of the country.

� Due importance should be given to river type small hydroelectric power plants,and considering the energy need of the country, domestic manufacturing andinstallation of machinery and equipment of these plants should be encouraged.

Acknowledgements

This work was supported by the Karadeniz Technical University Research fund.

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