Energy Vol. 13, No. 10, pp. 761-765, 1988 036&5442/&3 $3.00 + 0.00 Printed in Great Britain. All rights reserved Copyright @ 1988 Pergamon Press plc

SUSTAINABILITY OF FOSSIL FUELS AND ALTERNATIVE ENERGIES FOR TURKEY

E. TASDEMIROGLU

Mechanical Engineering Department, Middle East Technical University, Ankara, Turkey

(Received 11 Mnrch 1988)

Ahstra&---Reserves and production of fossil fuels in Turkey are discussed, as well as projections of production rates to the year 2010. Sustainability of fossil-fuel production has been estimated on the basis of presently known data. Fossil fuels will have a very limited lifetime. Bitumens, hydropower, geothermal energy, solar energy, wind power, biomass, and nuclear energy are appropriate alternative technologies. The potentials of these alternatives are given and recommendations are made to enhance their contributions.

FOSSIL-FUEL RESERVES

Turkey has highly diversified energy resources. Coal, lignite, asphalts, petroleum, natural gas, hydropower, geothermal energy, solar energy, and biomass are produced and used as primary energy sources. However, the conventional fuel reserves are not rich in quantity or quality. The WEC (World Energy Conference) Turkish National Committee has estimated that solar energy, geothermal energy and hydropower potentials among the renewables account for about 2, 4 and 1% of the world’s potentials, respectively.’ Total reserves of both conventional and non-conventional fuels are given in Table 1.1e3

Solid fuels Total technically and economically recoverable solid-fuel reserves, including coal, lignite,

asphalts, and bituminous schists, are about 1.5 btoe, which constitute 0.46% of the world coal reserves.

175 Mton of recoverable coal reserves account for about 0.2% of the world total. 40% of Turkey’s coal is found in northwest Anatolia along the Western Black Sea coast (Zonguldak). Of this, only 60% can be produced economically.4

Turkey’s lignites constitute about 3% of the world’s reserves. Lignite reserves are apparently very large and are spread over many regions in Thrace and Anatolia. The half of these reserves found in southwest Anatolia (Af$n-Elbistan) has a low calorific value (1100 kcal/kg).5 Lignites in Turkey generally contain lo-40% moisture, lo-30% ash and l-2% sulphur, while calorific values are between 1100 and 4500 kcal/kg. Productivity rates vary widely from one region to another. About 56% of open-pit mining and 23% of underground-mining would be economically feasible at present.

Asphalt mines are generally located in southwest Anatolia. High calorific value asphalts (2600-5536 kcal/kg) are used as solid fuels for heating in eastern Anatolia.’

The total amount of recoverable bituminous schists is about 880 Mton. Their calorific values are between 1000 and 1200 kcal/kg. There are some problems associated with mining and bitumen utilization.‘*5

Petroleum and natural gas

Total petroleum (20.3 Mton) and natural gas (31 billion m’) reserves are negligibly small compared to the world’s reserves. As much as 99.4% of proven petroleum reserves are in southwest Anatolia (Raman). The characteristics of these crudes, such as API degree, viscosity, etc., show large variations between different wells. There are scheduled exploration programs in southwest Anatolia, Thrace, the western Black Sea, and the western Taurus.6,7

Natural gas is found in Thrace and southeast Anatolia. The Hamitabat region in Thrace

761

762 E. TASDEMIRO~~LU

Table 1. Conventional and non-conventional energy sourcesin Turkey.

Reserves

Coal, Mton

Lignite, Mton

Asphalts, Mton

Bituminous

schists, Mton

Petroleum, Mton

Natural gas,

billion m3

Nuclear fuels, Kton

Natural uranium

Thorium

Hydropower, TWhfyr

Geothermal GWh/yr

Electricity

Thermal

Solar Energy, Ktoe/yr

Electricity

Thermal

Biomass energy, Mtoe

Economically

and

technically recoverable

175 1,377

5,905 8,143

38 75

808 1,525

20.3 20.3

15

8.8

118

31

8.8

380

118

Total

proven

4.5

31.1

8.8

26.4

17.2

holds the largest reserves. The production level for natural gas is very low since user sectors do not yet exist.6,7

Nuclear fuels

Uranium reserves are very small (8830 ton) and are found in different concentrations in seven regions of Anatolia. The share of the total world reserves is 0.1%. On the other hand, Turkey has a considerable amount of thorium (380 kton) in central Anatolia, which constitutes about 54% of the world’s thorium reserves. At present, thorium is not used commercially as a fuel in nuclear reactors.“’

PRODUCTION PROJECTIONS FOR FOSSIL FUELS

Production projections to 2010 are given in Fig. 1 for lignite, coal, petroleum, and asphalts. Figure 1 is based on official data. 1,2 Coal mines are managed by the state organization TTK (Turkish Coal Association). In the Zonguldak region, coal exploration is performed by deepening the underground mines each year. The deeper the mines, the harder the technical problems involved in recovery. The present production oscillates around 4 Mton/yr. After 2000, the production capacity is estimated to reach a stable level ?f 7.5 Mton/yr.4

Lignite exploration is controlled by the state organization TKI (Turkish Coal Management Authority) and some private companies. TKi estimates that total production may reach 80 Mton/yr in 2000. Production projections after 2000 are given by the WEC Turkish National Committee and are highly conjectural.

Asphalts are also produced by the TKi and the production capacity is estimated to remain nearly stable during future years.5

Fossil fuels and alternative energies for Turkey 163

1966 1990 1994 1998 2002 2oc6 2010

Years

Fig. 1. Production projections to 2010 for lignite, coal, petroleum and asphalts in Turkey.

Thermal power plants which use bitumens do not exist in the country. Bituminous schist developments are being planned jointly by TKI and TEK (Turkish Electricity Board).’

Petroleum and natural gas development programs were prepared by the two state organizations TPAO (Turkish Petroleum Cooperation) and PIGM (General Directory of Petroleum Affairs). 6,7 The aim is to produce 2.5 Mton of petroleum in 2000. Even though this production range is not very great, there are doubts about the sustainability of this schedule with known reserves to 2000. The present natural gas production is 720 million m3 and is expected to be stable to 2010.

SUSTAINABILITY OF FOSSIL FUELS

Sustainability of fossil-fuel production has been estimated by using the figures given in official sources.l** The estimates are made on two different bases. First, it was assumed that present production rates would not be altered in forthcoming years. In the second analysis, yearly increments for production rates are taken from governmental organizations. Since there are no estimates after 2010, it was assumed that yearly production rates would remain level beyond this time. In both cases, the sustainability of production after 1987 was calculated by considering all proven reserves (cf. Table 2).

Among the fossil fuels, the coal reserves have the longest projected lifetime and may last about 340 yr if they continue to be exploited at the present production rates. The figure drops to 173 yr if future increases in production rates are considered.

Production sustainability for petroleum and natural gas are the same for both of the specified assumptions, since future production schedules are expected to remain nearly level. Petroleum will last 9 yr longer under the given conditions. The figures for lignite, asphalts and natural gas are also not encouraging.

ALTERNATIVE ENERGY OPTIONS AND RECOMMENDATIONS

We conclude that, unless new fossil-fuel deposits are discovered, indigenous fossil fuels will have very limited lifetimes. Our estimates are very optimistic, since they include currently non-economical resources.

764 E. TASDEMIRO~LU

Table 2. Sustainability years of fossil fuels in Turkey.

Average

Reserves production

in 1987,

Ktonfyr

Coal

Lignite

Aspalts

Petroleum

Natural gas,

million m3/yr

4,000 344 173

52,185 156 60

850 89 60

2,317 9 9

720 43 43

t Yearly production is assumed to be the same during the

lifetime of the reserve at each year. * Projected increments on the average yearly production

are considered during the lifetime of the reserve.

Turkey, because of its geography and climatic conditions, is well endowed with new and renewable energy sources. These include bituminous schists, hydropower, geothermal energy, solar energy, wind power, and biomass. Nuclear energy may be another option. Hence, a programme of action for the development and utilization of these energy sources should be formulated in accordance with national plans and priorities. Their potentials and recommenda- tions to enhance their utilization will now be reviewed briefly.

Bituminous schist reserves amount about 6 Gton in Turkey.” Of these, 1.5 Gton have calorific values >850 kcal/kg. Interest in their use has been renewed in Turkey. Some organizations are planning to use this resource as a solid combustible.” Before making a decision to construct a thermal power plant using bitumens, anticipated changes in combustion efficiency and economics must be carefully investigated. These solid fuels may actually be unsuitable for applications. There are interesting proposals to make synthetic petroleum from bitumens, which may be a better approach. In view of the quality, amount and chemical composition of Turkey’s bitumens, the recommended techniques for development are underground heating and pyrolysis. 12,13

The total gross hydroelectric power potential and total energy production capacity are nearly 50,000MW and 112TWh/yr, respectively. On the average, 26% of the total gross potential may be economically usable. At present, only about 14% of the total hydroelectric power potential is exploited. The national development plan aims to harvest all of the hydroelectric power potential by 2010. The contribution of small hydroelectric plants to total electricity generation is estimated to be 4%. There remain some rivers for which the small hydro- potential has not been completely evaluated. Since total energy losses in hydroelectric power generation were about 3.6TWh in 1985, another issue involves improvement of electricity generation in hydropower stations.14

Turkey is one of the countries with significant geothermal potential. There exist about 4500 MW of geothermal energy that are usable for electric-power production. In addition, 31,000 MW of potential may be employed in thermal applications. There is in actual operation only one commercial geothermal power plant with 20.4 MW gross capacity. The share of geothermal energy production, both for electrical and non-electrical uses, is negligibly small at present in Turkey. Installations of new geothermal power plants are planned by the TEK.

Problems associated with the development and utilization of geothermal energy involve bureaucratic difficulties; technical problems deal with well drilling and there are also financial constraints.”

Fossil fuels and alternative energies for Turkey 765

Turkey lies in a sunny belt between 36 and 42”N latitudes. The yearly total radiation varies from a low of 5.5 GJ/m*-yr to a high of 6.7 GJ/m2-yr.‘6*‘7 Thanks to this geographical location, the solar-radiation potential of the country is sufficient to provide adequate energy for solar-thermal applications. In spite of this high potential, solar energy technologies are not now widely used, except for flat-plate solar collectors. Concentrating collectors for high-temperature generation and electricity production, metal melting, and industrial heat may be feasible in sunny regions. l8 The economics of photovoltaic applications in rural regions remain to be studied carefully.

There are a number of regions in Turkey with relatively high wind speeds. These have been classified into six wind regions, with a low of about 3.5 m/set and a high of 5 m/set at 10 m altitutude, corresponding to theoretical power productions between 1000 and 3000 kWh/m’-yr. There is at present no operating commercial wind-turbine machine. The economics of wind-energy systems in the country are still open to discussion. Comparisons are needed with conventional energy systems using life-cycle costing techniques.”

Among the renewable energy sources, biomass is one of the most promising because its share of total energy consumption in Turkey is relatively high at 22%. The total bioenergy potential is estimated to be about 17,201 ktoe, which equals the total energy consumption in the household sector. Thus, the bioenergy potential equalled 43% of the total energy consumption in the country in 1985. Past experience indicates the necessity of reorganizing the biogas programmes and the development of a digester for conditions existing in Turkey. The possibilities of energy recovery from industrial and municipal wastes should also be evaluated.3

Almost all known indigenous resources for electricity generation will be used after 2000. The best alternative for meeting increasing electricity demands is nuclear energy. The first nuclear power plant is expected to become operational in 1995. In order to prevent further delays, implementation of the first nuclear power plant should be accelerated, as should also be prospecting for uranium and thorium. ‘*”

REFERENCES

1. WEC Turkish National Commjttee, “Present and Future Energy Situation of Turkey,” (in Turkish), IV Turkish Energy Congress, Izmir, Turkey (1986).

2. Ministry of Energy and Natural Resources, “Energy Report 1985,” (in Turkish), Ankara, Turkey (September 1986).

3. E. Ta$demiroglu, Biomass 11, 81 (1986). 4. TTK, “Long-term Production Program for Coal,” (in Turkish), Report of the General Directory,

Ankara, Turkey (1986). 5. TKI, “Long-term Production Program for Lignite,” (in Turkish), Report of the General Directory,

Ankara, Turkey (1986). 6. TPAO, “Long-term Production Program for Petroleum and Natural Gas,” (in Turkish), Report of

the General Directory, Ankara, Turkey (1986). 7. General Directory of Petroleum Affairs, “Long-term Production Program for Petroleum and Natural

Gas,” (in Turkish), Report of the General Directory, Ankara, Turkey (1986). 8. MTA, “Reserve Studies,” (in Turkish), R eport of the General Directory, Ankara, Turkey (1986). 9. TEK, “Long, Term Production Program for Bitumens,” (in Turkish), Report of the General

Directory, Ankara, Turkey (1986). lo. M. F. AkkuS, “The Contribution of Bituminous Schists and Tar Sands to Energy Production and

Turkey’s Potential,” (in Turkish), IV Turkish E nergy Congress, Technical Session Presentations, pp. 125-144, Izmir, Turkey (1986).

11. WEC Turkish National Committee, “Results and Proposals of IV Turkish Energy Congress,” (in Turkish), IV Turkish Energy Congress, Izmir, Turkey (1986).

12. E. Ptitiir, M. Giineyman, M. Tolay, A. Aker, and E. Ekinci, “Production of Liquid Fuels from Goyniik and Seyitiimer Bituminous Schists by Pyrolysis,” (in Turkish), IV Turkish Energy Congress, Special Session Presentations, pp. 151-158, Izmir, Turkey (1986).

13. U. Inci, “Geology of Demirci and Burhaniye Regions, and the Possibilities of Bituminous Schists.” (in Turkish), Doctoral Thesis, Dokuz Eyliil University University, Izmir, Turkey (1983).

14. E. Tagdemiroglu, Energy 13, 245 (1988). 15. E. TaSdemiroglu, Energy 13, 549 (1988). 16. E. Tasdemiroglu and R. Sever, Sol. Energy 37, 205 (1986). 17. E. Taademiroglu, Sol. Wind Technol. 2, 85 (1985). 18. E. TaSdemiroglu and F. Arinc, Energy Convers. Mgmt 26, 299 (1986). 19. E. TaSdemiroglu, Energy 12, 1 (1987).

EGY 13:10-C