energy usage and cost in textile industry: a case study for turkey
TRANSCRIPT
Energy usage and cost in textile industry: A case study for Turkey
Harun Kemal Ozturk*
Mechanical Engineering Department, Engineering Faculty, Pamukkale University, Muhendislik Fakultesi,
20070 Camlık, Denizli, Turkey
Received 19 January 2004
Abstract
The Turkish textile industry holds a relatively important position in the world and thus plays a major role in
Turkey’s exports. Energy consumption is important for the textile industry in Turkey because it is the largest export
sector. Energy usage in the textile industry in Turkey is inefficient, and energy consumption has been growing very
rapidly due to population growth, rapid urbanization and industrial development. For future planning, it is important
to know the current specific energy consumption (energy consumption/production) and the energy intensity (energy
consumption/cost of energy) in order to estimate future energy consumption for the textile sector. In this study, a
survey has been carried out to show energy consumption, energy cost and the relationship between the energy usage
and textile production. The results of the energy survey have been presented in both figure and table form.
q 2005 Elsevier Ltd. All rights reserved.
1. Introduction
Turkey offers a large domestic market and holds a strategic location in the center of the Balkans,
Central Asia, the Middle East, North Africa, Eastern Europe, and Russia. Turkey has a wide spectrum of
bilateral economic relations with countries from all over the world. In this regard, Turkey has established
a solid economic basis for stable and fruitful cooperation with many countries. Turkey also benefits from
a geographical location that allows the country to take advantage of trade with emerging economies in
the region, including the trade in energy.
Turkey is one of the largest economies in the region achieving an average annual growth rate of 4.1%
over the past 20 years and a Gross National Product (GNP) that totaled $204 billion in 1998 [1].
Strong population growth and rapid urbanization have played an important role for development
Energy 30 (2005) 2424–2446
www.elsevier.com/locate/energy0360-5442/$ - see front matter q 2005 Elsevier Ltd. All rights reserved.
doi:10.1016/j.energy.2004.11.014
* Tel.: C90 258 212 55 32; fax: C90 258 212 55 38.
E-mail address: [email protected].
Table 1
Export of Turkey (US$ billion) [4]
Years 1994 1995 1996 1997 1998 1999 2000 2001
Export 18,106 21,636 23,225 26,261 26,973 26,587 27,775 31,340
H.K. Ozturk / Energy 30 (2005) 2424–2446 2425
of Turkey. In the period 1980–1990, Turkey’s export figures showed an average annual increase of 33%,
whilst the value of exports increased from $US 2.9 billion to $US 12.9 billion. The growth rate of exports
for 1992 and 1993 was 8.2 and 4.3%, respectively. In 1994, exports recorded an increase of 18% and
reached $US 18.1 billion [2]. In 1995, Turkish exports reached $US 21.6 billion with an increase of
19.5% [3,4]. In 2000, Turkish exports reached $US 31.34 billion, recording an increase of 12.8% over
2000 (see Table 1).
Turkey is a free market economy oriented towards Western markets. In 2000, the OECD countries
took a 68.6% share in the total exports of Turkey with a value of $US 18.7 billion. Among OECD
members, exports to the EU were $US 14.4 billion a figure that is equal to 52.5% of total exports [5].
Among the top 10 markets, Germany (with its 18.8% share) is the major market for Turkey. Turkey’s
second largest export market is the USA with a share of 11.2% whereas the UK constitutes the third
largest market with its share of 7.4% (see Table 2).
The energy requirement for an economy is sensitive to the rate of economic growth and the energy
intensity of producing sectors. The energy intensity of industry is a function of technological progress and
varies from sector to sector. Turkey has focused on improving the availability of energy, considering the
environmental impact of growth in the sector. Turkey’s energy strategy is aimed at satisfying demand
without any adverse impact on its economic growth in the country. Therefore, energy conservation is one
of the important objectives of energy policy in Turkey. Turkish domestic energy resources are highly
utilized and the economy is dependent on imports particularly of petroleum products. Turkey imports
nearly 50% of its energy requirements. The country spends 40–50% of its total export income to import
fuel, mainly crude oil and natural gas. Oil and natural gas meet nearly 60% of energy demand in the
country, with coal constituting nearly 25% of supply [6]. Sufficient and secure energy supplies are the top
priority of Turkey’s energy policy and industry. Therefore, it is vital for Turkey to improve the efficient use
of energy for textile industry as well. The aim of this study is to show the relationship among the energy
consumption, energy cost and production to understand the share of energy cost in the expenses.
Table 2
Major export partners, 2000 [3]
Value (thousand $) Share (%)
Germany 5,149,612 18.8
USA 3,059,863 11.2
UK 2,020,225 7.4
Italy 1,748,038 6.4
France 1,643,382 6.0
The Netherlands 869,469 3.2
Spain 682,917 2.5
Belgium-Luxembourg 639,244 2.3
Russian Federation 628,459 2.3
Israel 618,968 2.3
H.K. Ozturk / Energy 30 (2005) 2424–24462426
2. The place of textile industry in Turkish economy
Turkey, the 17th largest economy in the world, is an emerging country with a buoyant economy
challenged by a growing demand for energy. Steadily improving energy efficiency does not change the
deep need for further gains. Energy use in the textile industry in the country is still highly inefficient,
with huge possibilities for improvement. Turkey imports 65% of its energy, and expects energy imports
to increase by 72% by 2010, and 76% by 2020. This trend makes Turkey one of the fastest growing
energy markets in the world.
Turkey’s textile industry has shown a stable growth over the years. Among industrial products, the
textile and ready-to-wear industries have remained to play a major role in exports (see Table 3). The
textile sector is Turkey’s largest manufacturing industry and its largest export sector and a relatively
important position in the world. Turkey’s textile industry remains important to the economy. Turkey
ranks sixth in world exports of clothing with 3.5% of the total global apparel trade, and the second largest
supplier to the European Union, after China [8].
The GNP of Turkey decreased from $US 192.383 billion in 1997 to $US 148.166 billion in 2001
due to the general economic crisis (see Table 4). The textile sector is currently one of the most
important sectors in the Turkish economy in terms of GNP, employment and exports and as a whole
contributed 33.2% to Turkey’s export earnings in 2001 (see Table 3), 10% to the country’s GNP and
employed about one-third of all workers in manufacturing. Its share of the total industrial production
Table 3
Textile and apparel exports and their share in the total exports of Turkey [4,7]
Years Total exports
(1000 $)
Textile exports
(1000 $)
Share of textiles in
total exports (%)
Textile and apparel
(1000 $)
Share of textile
and apparel
in total exports (%)
1980 2,910,000 671,000 23.1 777,000 26.7
1981 4,703,000 915,000 19.5 1,217,000 25.9
1982 5,746,000 1,069,000 18.6 1,436,000 25.0
1983 5,728,000 1,055,000 18.4 1,599,000 27.9
1984 7,134,000 1,181,000 16.6 2,170,000 30.4
1985 7,958,000 1,151,000 14.5 2,087,000 26.2
1986 7,457,000 1,043,000 14.0 2,112,000 28.3
1987 10,190,000 1,133,000 11.1 2,861,000 28.1
1988 11,662,000 1,334,000 11.4 3,461,000 29.7
1989 11,625,000 1,338,000 11.5 3,786,000 32.6
1990 12,959,289 1,424,249 11.0 4,322,598 33.4
1991 13,593,539 1,374,357 10.1 4,593,707 33.8
1992 14,365,414 1,369,322 9.5 5,378,937 37.4
1993 15,345,000 1,457,490 9.5 5,615,487 36.6
1994 18,107,000 1,944,818 10.7 6,434,861 35.5
1995 21,637,041 2,130,665 9.8 8,319,167 38.4
1996 23,224,465 2,352,142 10.1 8,696,394 37.4
1997 26,261,072 2,730,421 10.4 9,819,090 37.4
1998 26,973,952 2,811,763 10.4 10,455,814 38.8
1999 26,588,264 2,733,641 10.3 9,878,694 37.2
2000 27,774,906 2,818,768 10.1 10,013,377 36.1
2001 31,339,991 3,060,947 9.8 10,396,803 33.2
Table 4
GNP and GNP per capita of Turkey (producers value at 1987 prices) [9,10]
1990 1997 1998 1999 2000 2001 2002 2003
GNP ($ million) 152.4 192.4 206.6 185.2 200.0 148.2 180.9 270.3
GNP per capita ($) 2.698 3.079 3.255 2.879 2.965 2.160 2.598 3.383
H.K. Ozturk / Energy 30 (2005) 2424–2446 2427
of the country is around 40%. Capacity utilization in this sector is high and production level is
around $10 billion.
Besides the Turkish textile industry, the Turkish home textile industry has also shown significant
growth in terms of production and exports. In recent years, the production of home textiles has shown a
stable increase due to the rise in domestic and external demand for home textiles. Almost all kinds of
home textiles are produced in Turkey. Turkish home textile manufacturers are mainly located in
Istanbul, Bursa, Denizli, Izmir, Kayseri, Gaziantep and Usak. Towel and bathrobe producers are mainly
concentrated in Denizli and Bursa. Besides meeting the domestic demand in Turkey, the Turkish home
textile sector is an important export earner for the country. As a division of the textile industry, the home
textiles sector with an export value of 859 million dollars and a 3.2% share in Turkey’s total exports in
1999, has been an important sub-sector for the Turkish economy [11].
Electricity consumption in Turkey has been growing rapidly—by approximately 10% a year and the
industrial sector accounted for almost 52% of the total electricity consumption. The Ministry of Energy
and Natural Resources (MENR) forecasts that industry’s share will increase further. In order to satisfy the
expected demand for electricity consumption, electricity generation capacity must increase. Electricity
generation peaked to 116.5 billion kW h (70% thermal, 30% hydro) in 1999. Approximately 119 billion
kW h of electrical energy, 2.5 billion kW h imported, were consumed in 1999. Energy demand forecasts
for the next 20 years predict Turkey’s electrical energy demand will reach 295 billion kW h in 2010 and
556 billion kW h in 2020 [12,13]. In order to meet this increased demand, it will be necessary for Turkey to
increase its existing generating capacity. Due to rapid and enormous increases in demand, Turkey’s power
generation sector will require massive investment. It will be necessary for the country to construct many
new power plants to ensure the reliable and cost-effective delivery of high quality energy.
Labor costs remain lower than in Europe, but much higher than in Asia. The price of electricity is
high, and there are hidden expenses in transport and customs. Electrical and heat energy are together the
most important production costs for textiles (about 10% of total input) [14]. It is important to know the
energy consumption for a textile firm to understand and control the usage (see Fig. 1).
The conservation and efficient use of energy in industry have for a long time been a priority of the
Government of Turkey. Electricity and heavy fuel-oil prices for some countries have been given in
Table 5. As can be seen in this table, the cost of electricity to Turkish industry is higher than in many
other countries although heavy fuel-oil is cheaper. Therefore, it is very important to know energy
consumption for textile industry. This paper is focused on a simple way estimating the energy
consumption for a textile factory.
3. Energy consumption structure of Turkish industrial sectors and the place of textile industry
National Energy Conservation Center (NECC) in cooperation with the Turkish State Statistics
Institute (DIE) carried out a detailed industrial database survey to define energy consumption, energy
Fig. 1. Comparison of the textile input as cost [15].
H.K. Ozturk / Energy 30 (2005) 2424–24462428
saving potential, the energy management approach and systems and technical infrastructure in the
industrial sector, such as boilers, motors and furnaces. Within the scope of this study, questionnaires
were sent to 1300 manufacturers consuming more than 500 tons of oil equivalent (toe) of energy [15].
According to the studies conducted by DIE in 1992 and 1995, on the basis of the results obtained from
approximately 1200 of these manufacturers, their total energy consumption of the places of
employment, which annually consume 500 ton oil equivalent (toe) or above, constitute 75% of the
industrial energy consumption of Turkey. Table 6 indicates the industrial sub-sectoral energy
consumption and the share of the cost of energy production of Turkey [16]. As can be seen in the table,
the iron and steel sectors take a large share (about 35%) of this consumption while textile and woven
industry take 5.9% of the total consumption. When the cost of the energy is investigated, this share
breaks down into 48% in the iron and steel sector, 32.5% in the ceramics industry, 55% in the cement
industry and 8–10% for the textile and woven industry [17].
In Turkey, since energy consumption of the industrial sector is 35% of the total energy consumption
and electricity consumption of the industrial sector is 54% of the total electricity consumption, this
Table 5
Electricity and heavy fuel-oil prices for some countries ($/Unit) [16]
Heavy fuel-oil for industry (ton) Electricity for industry (kW h)
Canada 208.98 0.03
Chinese 222.55 0.06
Germany 189.42 0.05
India 198.13 0.07
Italy 230.50 0.09
Japan 236.56 0.16
Korea 285.27 0.06
Spain 199.35 0.05
Turkey 191.17 0.09
United Kingdom 202.13 0.05
United States 182.50 0.04
Table 6
Industrial sub-sector energy consumption and the share of the cost of energy production of Turkey [18,19]
Industry Total energy (toe) Rate of industrial
consumption (%)
Rate of energy in
total cost (%)
Iron/steel 4,863,328 34.9 11.5 and 48
Non-ferrous metals 312,947 2.3 6.2 and 47.4
Ceramics 627,789 4.5 32.5
Cement 2,736,165 19.7 55
Glass 234,898 1.7 22–42
Paper and cellulose 468,823 3.4 9–30
Textile and woven 822,305 5.9 8–10
Petro chemical 606,423 4.6 28.5
Main chemicals 308,138 2.2 24
Chemical fertilizer 718,962 5.2 40
Petrol refineries 406,006 2.9 4
Dye, varnish 7149 0.05 1.6
Medicine 17,693 0.12 1.5
Soap, cleaners 41,190 0.3 2.1
LPG 34,082 0.24 1
Others 558,000 4 –
Forest products and furniture 72,143 0.52 6
Metal furniture 41,251 0.3 4
Flour products 8132 0.06 4
Tea 72,053 0.52 3.5
Sugar 415,759 2.99 8.5
Oil 137,731 0.99 3.7–6
Vegetable and fruit industry 65,762 0.47 6.44
Tobacco/beverage 107,287 0.77 0.7–6
Total 13,923,448 100
H.K. Ozturk / Energy 30 (2005) 2424–2446 2429
sector is considered with the highest priority when energy conservation studies are discussed.
Besides these, it is estimated that industrial energy consumption of Turkey will be increased from 34.7%
in 1996 to 37% by the year 2000 and 56% by the year 2010. These percentages show that the structure of
the Turkish industrial sector should be investigated from the point of energy conservation [19].
Turkish textile industry is one of the oldest and biggest industrial sectors in Turkey. Since this
industry is energy-intensive, it is very important to optimize its energy consumption and hence energy
conservation. Industrial processes of textile use large amounts of fuel and electricity. It is very important
to minimize the energy cost and energy consumption for the textile industry to reduce the cost and to
rival. Increasing global competition puts high demands on Turkish textile companies, one of which is an
increased demand for cost efficiency. One important factor in reaching higher cost efficiency is to reduce
energy cost and to use energy efficiently.
Kalliala and Talvenmaa [20] carried out a survey for six textile firm in Finland to create an
environmental impact profile for wet processing. He concentrated on the yarn manufacturing, weaving
process, dyeing machines, wet processing of knitted fabrics and wet processing of woven fabrics. Tang
and Mohanty [21] investigated the energy efficiency improvement by using cogeneration for Thailand. A
comprehensive report [22] has been prepared by United Nations Industrial Development Organization
H.K. Ozturk / Energy 30 (2005) 2424–24462430
(UNIDO) to show the potential energy saving pint for textile industries in Japan, Malaysia and
Indonesia. Tiwari [23] carried out a study to calculate energy intensities for different sectors in Indian
economy. The results indicate that sectors like coal tar products, wool, silk, synthetic and textile
worsened during 1983–1990 as the point of energy intensity. Mozes et al. [24] examined the efficiency of
the conventional textile washing process from the point of exergy and they show that the electrical
heating process consumes most exergy. Deventer [25] carried out a feasibility study on superheated
steam drying of paper and textile. He indicated that drying with superheated steam in direct contact with
the paper or textile web offers great advantages over conventional ways of drying with respect to energy
efficiency, drying rate and quality aspects. Muneer et al. [26] presented alternative and sustainable
solution for water heating for textile industry in stead of fossil fuel for dying process which is one of the
major energy consuming areas in textile industry.
4. Characteristics of energy consumption for textile industry
4.1. Types of energy used in the textile industry
In general, energy in the textile industry is mostly used in the forms of: electricity, as a common
power source for machinery, cooling and temperature control systems, lighting, office equipment, etc.;
oil, LPG; coal; or natural gas as a fuel for steam generators.
Table 6 shows the distribution of energy consumption in the sub section of textile industries in Turkey.
These sections include textile and wearing apparel, weaving, spinning, weaning, dyeing, drying and
finishing and knitting. Textile and wearing apparel and weaving have the highest energy consumptions. In
summary, electricity, natural gas and fuel-oil are the main energy source for the industry.
5. Energy conservation management for textile industry
5.1. Importance of energy management
Industrial processes for the textile use large amounts of fuel and electricity. The increases in energy
cost and energy consumption force industrial companies and government agencies to use energy more
efficiently. Decreasing energy losses and recovering the lost energy are of great importance. Many
industrial-heating processes generate waste energy. This waste energy in form of heat can be removed
and used for other useful applications for the energy saving purpose.
In order to optimize energy saving in a company, it is necessary to enhance the awareness, improve
the knowledge and obtain the participation and cooperation of everybody involved in the production
process. Energy management is relevant to a wide range of departments within a company to provide
continuity for energy saving. While it is necessary for engineers and technicians with specialized
technical knowledge to play a central role in energy conservation efforts, the implementation of an
energy management program itself should not be left to a handful of specialists or specialized sections.
Rather, it is desirable to address the task company-wide, for example, by setting up an ‘Energy
Management Committee’. Also, it is essential to get the support of the head of the companies to
achieve desirable result. It has been seen at the textile factories in Turkey that although there is an
H.K. Ozturk / Energy 30 (2005) 2424–2446 2431
energy manager at the companies, ‘Energy Management Committee’ has not been established and the
head of the companies is not aware of the importance of energy management program for the energy
saving.
Energy efficiency improvements for the textile industry in Turkey refer to a reduction in the energy
usage for a given energy service (production, heating, lighting, etc.). This reduction in the energy
consumption is not necessarily associated to technical changes, since it can also result from a better
organization and management or improved economic efficiency in the sector (e.g. overall gains of
productivity). Energy efficiency is first of all a matter of individual behavior and rationale of energy
consumers. Avoiding unnecessary consumption of energy or choosing the most appropriate equipment
to reduce the cost of the energy contribute to decrease individual energy consumption without
decreasing individual welfare and production. It is obvious that it also contributes to increase the overall
energy efficiency of the national economy.
6. Use of electricity efficiently in the factories
In the textile industry, the electricity is used for production, lightening, HVAC, etc. The collected data
for the four textile factories is given in Table 7. The production takes a large share (average 77%) of the
total electricity consumption. Lightening and HVAC take about 5 and 17%, respectively.
6.1. Production
The textile industry uses a vast number of electric motors, and most of them are relatively small.
While some of conventional machines were driven by a single motor, many modern machines utilize
multiple motors with a control board for controlling the movement of each motor.
Most electrical motors are designed to run at 50–100% of rated load. Maximum efficiency is usually
near 75% of rated load. A motor’s efficiency tends to decrease dramatically below about 50% load.
Overloaded motors can overheat and lose efficiency. Therefore, for the textile industry, it is useful to use
variable loads include two-speed motors, adjustable speed drives, and load management strategies that
maintain loads within an acceptable range to work at variable load. It is advisable to operate the
electrical motors at its nameplate for obtaining high efficiency. It has been noted that most of the motors
at the industry is oversize and therefore, and they run below the 50% load. Therefore, it is advisable to
change the motors with appropriate size.
Table 7
Share of electricity usage for four textile factories
Name of
factories
Production Lightening Heating and ventilation
kW h/month % kW h/month % kW h/month %
A 206.6400 80 154.980 6 361.620 14
B 2673.300 70 114.570 3 1031.130 27
C 798.600 66 121.000 10 290.400 24
D 84.423 91 1.855 2 6.494 7
H.K. Ozturk / Energy 30 (2005) 2424–24462432
6.2. Lighting
Due to its nature of operations, the share of lighting in total electricity use is relatively high energy. By
switching from tungsten bulbs to fluorescent lamps, considerable electricity savings can be achieved. In
Turkey, fluorescent lamps are widely used in textile industry. In order to use electricity efficiently for
lighting, it is important to re-examine whether the light source is utilized in the most efficient way. In this
survey, it was found that none of the factories measured the lightening level in the working environment.
If it is done, over-lightening could be eliminated at the companies. Natural lightening at the factories
could be used in order to minimize electricity consumption.
6.3. HVAC systems
Heating, Ventilating, and Air Conditioning (HVAC) relates to systems that perform processes
designed to regulate the air conditions within factories for the comfort purposed and for some processes.
HVAC systems condition and move air into the factories to create and maintain desirable temperature,
humidity, ventilation and air purity. For the textile industry, during weaving process, temperature range
should be about 30 8C, while the relative humidity is approximately 80%. HVAC process consumes
high-energy rate. As can be seen from Table 7, about 27% of total electricity is consumed by HVAC
systems for the factories which survey is carried out. In awareness of energy, the computer revolution
has given the tools to optimize the design of the building and to compute the cost of energy. For the
energy saving and use the energy efficiently, recommended guidelines should be followed closely so that
too much fresh air is not introduced unnecessarily. Also some conditioned air after filtered can be used
with the fresh air to reduce the electricity consumption.
7. Use of fuel efficiently in the factories
It is vital to encourage the manufacturers to adopt a comprehensive approach to energy use that
includes assessing industrial systems and evaluating potential improvement opportunities. Efficiency
gains in compressed air, motor, process heating, pumping, and steam systems can be significant and
usually result in immediate energy and cost savings.
During data collection in the textile factories, it has shown that the industrialist is worried about the
consumption of huge quantity of energy and its day-by-day increased cost. In the following sections
potential energy saving possibilities has been given briefly.
7.1. Selection of fuel
Fuels utilized in the textile industry in Turkey have already gone through a switch over from coal
to fuel-oil and natural gas (see Table 8). Recently, decreasing the energy cost is one of the most
important issues for the industry. In order to reduce the cost, the heating systems have been
converted to natural gas and lignite from fuel-oil, because their price is currently lower than the fuel-
oil. Turkey has limited reserves of oil and natural gas, but proven reserves of lignite in the order of
8.4 billion tones [28]. Lignite is cheaper than natural gas as an input fuel for the industries, but
natural gas-using equipment tends to have lower capacity cost and can be built in smaller increments.
Table 8
Energy consumption of each specialized technical field in Turkish textile industry. group and fuel type [27]
Weaving Spinning, weaning, dyeing,
drying and finishing
Knitting
toe % toe % toe %
Electricity 241.843 24.90 204.732 32.19 18.080 3,96
Steam 13.881 1.43 7.051 1.11 4.731 10.37
Natural gas 283.522 29.19 242.123 38.06 29.572 64.83
Fuel-oil 260.452 26.81 218.620 3.44 2.952 6.47
Central Heating fuel 38.593 3.97 33.585 5.28 4.073 8.93
Coal 84.198 8.67 79.938 12.57 568 1.25
LPG 48.915 5.04 46.806 7.36 1.911 4.19
Total 971.404 100.00 636.097 100.00 45.615 100.00
H.K. Ozturk / Energy 30 (2005) 2424–2446 2433
Turkish lignite has low calorific value and high sulphur, dust and ash content and causes greater air
pollution. Therefore, lignite is used especially in electricity generation and not widely used for
industry. It could be useful to use lignite with purification at the industry to reduce the energy cost.
Another solution could be to use geothermal energy which is very convenient for the textile industry
in Turkey [29,30].
8. Finding energy losses
In this section, some of energy lost and their effect on the energy lost will be given. Following are
some of the major sources from where energy is lost in various forms.
8.1. Energy loss through hot water discharge and heat recovery from wastewater
The use of heat recovery systems for textile firms can help them to improve energy efficiency by
reducing the requirement for hot water and steam in their manufacturing processes. Decreasing energy
losses and recovering the lost energy are of great importance. As known, heating processes in textile
industry generates waste energy. Heat energy can be recovered from the hot wastewater streams using a
heat exchanger. Use of the waste heat recovery systems can help to decrease energy consumption and
utilize the heat produced for the other process.
Steam condensate discharges are hot and clean water streams. These streams can be used as boiler
feed water or for preparation of dye baths. These options not only reduce water consumption and
wastewater quantities, but also result into substantial energy savings. Drying is often one of the most
energy-intensive operations in textile processes and such dryers exhaust large amounts of warm and
moist air.
Any boiler with continuous blowdown exceeding 5% of the steam rate is a good candidate for the
introduction of blow down waste heat recovery. Larger energy savings occur with high-pressure boilers.
Some streams are clean whereas others are heavily contaminated with number of chemicals and dyes in
textile industry. Most of the wastewater streams are discharged at the temperatures of 60–70 8C.
H.K. Ozturk / Energy 30 (2005) 2424–24462434
9. Energy losses through leakages and improper maintenance
In most of the textile companies during data collection, it has been seen that most of the pipelines and
equipments are not properly installed and therefore, steam and hot water is lost through leakages. It is
very difficult to estimate the quantity and cost of leakages but it is obvious that the leakage of hot water
and steam results in substantial energy loss. Generally, the condition of piping and insulation is not up to
the standard due to the fact that preventive maintenance is not being given due consideration. One of the
reasons for this negligence may be due to production load in which machine shut down for repair is
difficult, and production is not wanted to stop for maintenance.
It has been noted that steam requirement has not been properly calculated and when ever needed, new
boilers installed when the factories are expanded. Steam usage is generally not optimized; reasons for
excess usage and wastage of steam are the unnecessary supply of steam to the bath even after attaining
required temperature. Steam traps used in the factories are mostly not functioning properly, therefore,
steam escapes along with steam condensate. It was noted that there are some non-functional steam traps,
rather being repaired or replaced. Since high pressure and high temperature steam flow through the pipe
(see Table 9), corroded pipes and valves, as a result of improper maintenance, also contribute in steam
and hot water loss. Steam control valves are generally not found in the machines. It was noticed that the
old machines are not equipped with energy controllers. Consequently, it could be argued that steam
efficiency can offer the companies significant energy conservation and environmental benefits.
10. Energy loss from the pipelines and machines due to lack of insulation
The steam need in the textile industry is widespread so that steam losses due to heat radiation from
steam transportation pipes and pressure drops are considerable. The walls and combustion regions of
boilers and pipeline should be insulated with insulating materials to unnecessary loss of thermal energy
and to prevent leakage. For steam transportation over long distances, low pressure and large-diameter
piping should be preferred to high pressure and small diameter. Valves and pipe curbing also cause to
pressure reducing and energy loss. Therefore, as pressure losses around bends are great, it is desirable to
make their radii large. It has been seen that most of the steam, steam condensate and hot water carrying
Table 9
Information about the boilers capacity, pressure and temperature
Capacity Unit Type of product Pressure (bar) Temperature (8C)
Factory A 50 ton/h Steam 7 191
3000.000 kcal/h Heated oil 4 230
Factory B 38 ton/h Steam 14 203
8 ton/h Steam 8 170
13,000.000 kcal/h Heated oil 5 250
Factory C 39 ton/h Steam 7 170
10,700.000 kcal/h Heated oil 4 240
Factory D 15 ton/h Steam 10 184
2.500.000 kcal/h Heated oil 2.5 260
H.K. Ozturk / Energy 30 (2005) 2424–2446 2435
pipelines are not equipped with proper insulation. It was noted that most part of the insulation was
weared away at various places because of improper maintenance.
Heat lost to ambient air occurs from machines conducting reactions, washing and drying at hot states
especially desizing, bleaching, jiggers machines and dryers, because they are mostly not insulated or
some of them insulated. It is well known that the quantity of heat dissipation is the function of the
temperature difference between inside hot machines and out side cold air and the surface area of the
machine. Proper insulation provides resistance to convectional heat transfer with the advantage of less
steam and fuel consumption in heating contents up to the required temperature. In addition, in terms of
safety, insulation reduces the outer surface temperature of the steam piping, and machines, which lessens
the risk of burns. A well-insulated system also reduces heat loss to ambient workspaces, which can make
the work environment more comfortable.
11. Boiler insulation and control system
Thermal insulation of the boiler provides important safety, energy savings, and performance benefits.
The selection and design of boiler insulating materials depend largely on the age and design of the boiler.
Since the insulating lining is exposed to high temperatures and is subject to degradation, it should be
periodically inspected and repaired when necessary.
Boiler control systems should be designed to protect the boiler and to ensure proper boiler operation.
These systems should include the combustion control system, flame safeguard, water level control, and
fuel control to use the energy efficiently. Steam flow meters could be helpful in evaluating the
performance of the system and also it can provide useful data in assessing boiler performance,
calculating boiler efficiency, and tracking the amount of steam required by the system.
12. Energy loss through flue gases and hot air
In each production process of the textile industry, the heating and cooling of gases and liquids are
frequently required. This is done through heat exchange between different fluids, and in order to avoid
contamination or chemical reaction due to their direct contact, heat exchangers are used to carry out
indirect heating and cooling. It is important to use the right heat exchanger for the intended purpose.
Boiler flue gases contain substantial heat energy. This energy can be utilized to preheat the boiler feed
water through economizer but at present in the most of the textile factories in Turkey, it is not being
utilized.
13. Combustion control system
Operating the boiler with an optimum amount of excess air will minimize heat loss and improve
combustion efficiency. To provide enough air for the amount of fuel used in industrial boilers, fans are
typically required. Dampers, inlet valves, or variable speed drives typically control the amount of
air allowed into the boiler. In order to regulate the fuel air mixture, the combustion control system could
be used to achieve safe and efficient combustion. The stack temperature and flue gas oxygen
H.K. Ozturk / Energy 30 (2005) 2424–24462436
(or carbon dioxide) concentrations are primary indicators of combustion efficiency. In practice,
combustion conditions are never ideal, and additional or ‘excess’ air must be supplied to completely burn
the fuel. In order to determine the correct amount of excess air, it is necessary to analyze flue gas oxygen or
carbon dioxide concentrations. Also, it could be useful to establish the combustion control systems to the
factories.
14. Using the dyeing and drying process more efficiently
The dyeing and drying of textiles are the two processes that need a large amount of energy for heating
in textile industry. Mostly, Fuel-oil or LPG is used for these two processes. Whereas hot water at 80 8C is
required for the dyeing process, the drying process needs steam to dry the wet textiles. In drying process,
the textile is passed over the hot surface of a cylinder and steam from a boiler heats the inside of the
cylinder. The singeing workshop in the factory has a large demand for hot water for the washing of
fabric. At the same time, large quantities of waste energy are produced in the form of hot humid air from
drying and in warm waste water from the washing processes. In order to increase the efficiency in the
textile industry, it is necessary to focus on these processes.
Drying is a time-consuming, energy-intensive and expensive process after most dyeing and/or finishing
process in the textile industry. The term ‘drying’ involves removal of water or volatile solvent from a solid
(generally the former) by thermal energy. Textile processing industries use large amounts of steam for
drying. The raw material is very humid in dye-printing, lavation and the other processes. The humidity of
the fabric is reduced by means of dryers. During drying, the warm moist air is sent to the atmosphere.
However, this waste heat should be used in the drying machines. But the processed waste-air is humid and
generally polluted with fiber, dust and chemical materials and therefore, polluted air cannot be used again
in the process. Fresh, dry and hot air should continuously be circulated in the drying system. In order to
get the temperature level, which is necessary for the system, the air is pre-heated by the waste stream and
re-used. Boiler flue gases could be used for drying with some recovery system installation.
It is important to know the specific energy consumption and the energy intensity (the energy use per
kilogram) of the textile sector to estimate the total energy consumption. It is important for the individual
textile firms and also for Turkey to reduce the energy consumption at least to that of the rivals in the
market. The energy requirement of the Turkish economy is sensitive to the rate of economic growth and
the energy intensity of the production sectors.
15. Results and discussion
In this study, a survey has been carried out to show energy consumption, energy cost and the
relationship between energy usage and production. The results of the energy survey and analysis show
that specific fuel consumption is high for the textile industry. The survey was carried out for four textile
factories in Denizli which is located near the export city of Izmir in Turkey.
This study is based on personal in-depth interviews including four companies. One of these four
factories was big size, one is small and the others were middle size. The criterion for selecting factories
was to get an overview of the textile sector for high-energy-intensive companies, mid-energy-intensive
companies and low-energy-intensive companies. During the data collection, questions have been raised
Fig. 2. Organization chart of a common textile factory in Turkey.
H.K. Ozturk / Energy 30 (2005) 2424–2446 2437
to the people responsible for energy questions, such as manager of the factories, managers for energy,
maintenance, and those responsible for economic matters. The organization chart of the common textile
company in Turkey is given in Fig. 2. The amount of electricity measured with counter. Fuel values
(coal, fuel-oil, or LPG) are measured when it was bought. The amount of energy consumption
(electricity or fuel) was taken from energy manager. If an energy manager is not employed at the factory,
the data was obtained from the manager. The price and annual energy cost for electricity, fuel-oil and
LPG were taken from financial officer.
The factories chosen were one small, one big and two-middle sized. Brief information about the
factories and their working areas are correspondingly given in Table 10. The production fields and types
of the factories are dyeing, weaving, plain fabric and bathrobes as shown in the table. The process chain
of dying and finishing and weaving and energy use of the factories are described in Figs. 3 and 4,
respectively.
The amount of energy consumption, price, and annual energy cost for electricity, fuel-oil and LPG
are given in Table 11. As can be seen from the table, energy price of electricity, fuel-oil and LPG are
8.7 ¢/kW h, 26 and 66 ¢/kg, respectively. The unit energy price does not change with the amount of
consumption although the annual energy consumption and cost are different for each of the factories.
Table 10
Information for the survey textile firms and their working area
Factories Factory A Factory B Factory C Factory D
Year of foundation 1995 1985 1999 1960
Number of personnel 180 200 65 500
Production field Dyeing Weaving, dyeing Dyeing Weaving, dyeing
Production type Plain fabric Bathrobes, plain fabric Plain fabric Bathrobes, plain fabric
Fig. 3. Weaving process and energy use.
Fig. 4. Dyeing and finishing process for fiber and yarn and energy use.
H.K. Ozturk / Energy 30 (2005) 2424–24462438
Table 11
The type and consumption of energy for the factories
Energy type Energy consumption Energy price Annual energy cost ($)
Factory A Electricity 2,583,000 kW h 8.7 ¢/kW h 224,721
Fuel-oil 3,740,000 kg 26 ¢/kg 972,400
Total 1,197,121
Factory B Electricity 3,819,000 kW h 8.7 ¢/kW h 332,253
Fuel-oil 2,690,000 kg 26 ¢/kg 699,400
LPG 156,000 kg 66 ¢/kg 102,960
Total 1,134,613
Factory C Electricity 1,210,000 kW h 8.7 ¢/kW h 105,270
Fuel-oil 2,005,000 kg 26 ¢/kg 521,300
Total 626,570
Factory D Electricity 927,920 kW h 8.7 ¢/kW h 80,729
Fuel-oil 1,485,000 kg 26 ¢/kg 386,100
Total 466,829
H.K. Ozturk / Energy 30 (2005) 2424–2446 2439
Monthly production of textile goods and their corresponding values in terms of weight are given in
Table 12 for each factory. As shown in the table, the production rates are variable through the year. The
production increases in spring and summer term and decreases in autumn and winter.
Energy cost and energy consumption of the factories is given in Table 13. Electricity, fuel-oil and
LPG usage by amount has been converted into the same units as Gcal. For electricity, percentage
of electricity cost is about three times higher than percentage of energy consumption by value,
while for fuel-oil, percentage of energy cost is less than percentage of energy consumption by value
(Table 13). It is noted that unit cost of electricity, fuel-oil and LPG are 101, 27 and 58.9 $/Gcal,
respectively.
Table 12
Monthly production of factories (kg)
Months Production
Factory A Factory B Factory C Factory D
Product;
plain fabric
Product: plain
fabricCbathrobe
Product:
plain fabric
Product: bathrobeCplain fabric
January 600,000 480,000 165,000 71,409
February 590,000 490,000 180,000 124,920
March 620,000 505,000 185,000 95,172
April 630,000 510,000 175,000 250,693
May 620,000 510,000 180,000 346,648
June 615,000 520,000 185,000 180,111
July 655,000 525,000 220,000 233,639
August 613,000 525,000 235,000 213,893
September 605,000 500,000 215,000 113,802
October 590,000 505,000 190,000 166,707
November 585,000 500,000 185,000 129,860
December 585,000 490,000 180,000 62,209
Total 7,308,000 6,060,000 2,295,000 1,989,063
Table 13
Energy consumption and energy cost of the factories
Factory Energy consumption Energy consumption by
value and percentage
Energy cost Unit energy
cost ($/
Gcal)Type Amount Gcal % $ %
A Electricity 2,583,000 kW h 2224 6 224,721 18.8 101
Fuel-oil 3,740,000 kg 35,904 94 972,400 81.2 27
Total 38,128 100 1,197,121 100 31.4
B Electricity 3,819,000 kW h 3,284 11 332,253 29.3 101
Fuel-oil 2,690,000 kg 25,824 84 699,400 61.6 27
LPG 156,000 kg 1747 5 102,960 9.1 58.9
Total 30,855 100 1,134,613 100 36.8
C Electricity 1,210,000 kW h 1041 5 105,270 16.9 101
Fuel-oil 2,005,000 kg 19,248 95 521,300 83.1 27
Total 20,288 100 626,570 100 30.9
D Electricity 927,920 kW h 798 5 80,729 17.3 101
Fuel-oil 1,485,000 kg 14,256 95 386,100 82.7 27
Total 15,054 100 466,829 100 31
H.K. Ozturk / Energy 30 (2005) 2424–24462440
Fig. 2 shows the share of energy consumption and energy cost for the four factories given in Table 13.
As can be seen in the figure, electricity is more expensive than fuel-oil and LPG. Amongst the three
energy sources, the cheapest is fuel-oil.
It is very important to know the relationship between energy consumption, energy cost and the
production. Fig. 5 shows the relationship between energy consumption and energy consumption per
kilogram, production and energy cost per production and the relationship of all this to the cost per unit of
Fig. 5. Relationship between energy consumption, energy cost and the production.
Fig. 6. Percentage of energy usage and cost.
H.K. Ozturk / Energy 30 (2005) 2424–2446 2441
energy. As can be seen in the figure, when production decreases, the energy cost per unit of production
increases. Also, when energy consumption increases, the energy consumption per kilogram reduces.
Cost per unit of energy is almost constant for factories A, C and D, while it is higher for factory B due to
the higher usage of electricity. As can be easily seen from Fig. 6, the electricity consumption for factory
B was almost twice that of the others.
Tables 14 and 15 show the changing use of electricity and fuel-oil with the month, respectively.
As can be seen from the tables, the electricity and fuel-oil consumption increases late in the summer.
Table 14
Monthly electricity usage for the year 2001
Months Electricity
A B C D
kW h/
month
Gcal/
month
kW h/
month
Gcal/
month
kW h/
month
Gcal/
month
kW h/
month
Gcal/
month
January 200,000 172 290,000 249 90,000 77 56,556 49
February 205,000 177 295,000 254 95,000 82 97,082 83
March 205,000 177 305,000 262 100,000 86 105,663 91
April 228,000 196 310,000 267 105,000 90 84,420 73
May 215,000 185 310,000 267 105,000 90 83,779 72
June 220,000 189 325,000 279 100,000 86 78,120 67
July 230,000 198 330,000 284 100,000 86 69,300 60
August 230,000 198 330,000 284 110,000 95 88,200 76
September 215,000 185 335,000 288 105,000 90 61,740 53
October 210,000 181 335,000 288 95,000 82 70,560 61
November 215,000 185 340,000 292 100,000 86 78,120 67
December 210,000 181 314,000 270 105,000 90 54,180 47
Total 2,583,000 2224 3,819,000 3284 1,210,000 1040 927,720 799
Table 15
Monthly fuel-oil usage for the year 2001
Months Fuel-oil
A B C D
kg/
month
Gcal/
month
kg/
month
Gcal/
month
kg/
month
Gcal/
month
kg/
month
Gcal/
month
January 300,000 2880 195,000 1872 164,736 1584 109,400 1050
February 305,000 2928 190,000 1824 169,728 1632 120,500 1157
March 310,000 2976 200,000 1920 159,744 1536 129,300 1241
April 315,000 3024 210,000 2016 154,752 1488 133,700 1284
May 315,000 3024 210,000 2016 169,728 1632 144,400 1386
June 310,000 2976 240,000 2304 174,720 1680 144,500 1387
July 320,000 3072 245,000 2352 174,720 1680 143,800 1380
August 315,000 3024 250,000 2400 164,736 1584 120,600 1158
September 315,000 3024 240,000 2304 174,720 1680 96,800 929
October 310,000 2976 240,000 2304 164,736 1584 120,800 1160
November 315,000 3024 250,000 2400 169,728 1632 122,600 1177
December 310,000 2976 220,000 2112 159,744 1536 98,500 946
Total 3,740,000 35,904 2,690,000 25,824 1,530,048 19,248 1,484,900 14,255
H.K. Ozturk / Energy 30 (2005) 2424–24462442
The reason for this is that, the quota of the Turkish textile industry is completed until late in
the spring and therefore production decreases later in the year. At the end of summer, production
starts again for the next year (see Table 16). Therefore energy usage and also production increases in
the summer.
The variation of annual production with annual energy consumption has been shown in Fig. 7. As can
be seen, there is a linear relationship between production and energy consumption. The figure was
produced from the data of six factories. The other two data sets were taken from the study (for Figs. 7–9)
Table 16
Monthly textile production for the year 2001 (ton/month)
Months Amount of production
A B C F
January 600 480 165 71
February 590 490 180 125
March 620 505 185 95
April 630 510 175 251
May 620 510 180 347
June 615 520 185 180
July 655 525 220 234
August 613 525 235 214
September 605 500 215 114
October 590 505 190 167
November 585 500 185 130
December 585 490 180 62
Total 7308 6060 2295 1990
Fig. 7. Variation of annual energy consumption with annual production.
H.K. Ozturk / Energy 30 (2005) 2424–2446 2443
[31]. As can be seen in Figs. 7–10, R is very close to 1. This means that the data were in accordance.
The annual production in the study changes from 1000 to 30,000 ton. If the annual production of any
factory is known, the annual energy consumption may be estimated using Fig. 7. Similarly, the variation
of annual production with annual electricity and annual heat energy consumption (fuel-oil, LPG or coal)
have been given in Figs. 8 and 9.
In Fig. 10, the relationship between annual production and energy cost has been shown for the four
factories considered in this study. It can be seen from the figure that total energy costs increase with
production as expected.
Fig. 8. Variation of annual electricity consumption with annual production.
Fig. 9. Variation of annual heat energy consumption with annual production.
H.K. Ozturk / Energy 30 (2005) 2424–24462444
16. Conclusions
Textile industry is very important for Turkish exports and the economy in general. It has been
recorded that energy takes about 10% of total cost of production. In this paper, the relationship between
energy consumption, energy cost and production has been presented.
It has been found that the total energy consumption, electricity consumption and heat energy
consumption increases linearly with production. These results can be useful not only in estimating the
cost of energy for any given production levels but also in estimating the reduction in production costs for
any energy saving and conservation measures proposed.
For a further study, the number of the factories should be increased to get more reliable result. Since
the number of the factories the survey carried out is limited, the values could not reflect the exact data.
Fig. 10. Variation of annual energy cost with annual production.
H.K. Ozturk / Energy 30 (2005) 2424–2446 2445
However, they can give an approximate idea about relationship among the energy consumption,
production and cost for Turkish textile industry.
In order to implement an actual energy management program, it is important to grasp the current level
of energy consumption and its actual conditions in detail. Therefore, it is useful to start with learning the
relationship among the production, energy consumption and cost to start energy management system.
Acknowledgements
The author is grateful for the support provided for the present work by textile factories Deba, Irem
Tekstil, Kucuker Tekstil and AFZ Tektil. He would like to thank three anonymous referees and the
Editor-in-Chief of this journal, Professor Noam Lior, for their valuable and constructive comments on
the paper.
References
[1] Hr-Net. Department of State Background Notes, Turkey; 1999. http://www.hri.org/docs/USSD-Background/Turkey.
1999-10.html.
[2] TE, Turkish Economy. Exports; 2002. http://www.turizm.net/economy/exports.html.
[3] Exports; 2002. http://www.dtmtokyo.org/foreigntradeexports.htm.
[4] TR, Turkish Republic. Turkish Treasury, Change of External Dept Payment; 2002. http://www.hazine.gov.tr/stat/
egosterge/Tablo-10.htm [in Turkish].
[5] FTP, Foreign Trade Policy. IGEM, Export Promotion Center; 2003. http://www.igeme.org.tr/introeng.htm
[6] WEC, World Energy Council. A report of the World Energy Council. Pricing energy in developing countries; 2001.
[7] CTTA, Chamber of Turkish Textile and Apparel. Export and import of Turkish textile industry, ITKIB; 2002. http://www.
itkib.org.tr/res800/Istatistik/yillikihracat/YillarTeks_Konf_ihr.htm [in Turkish].
[8] WTAD, The Washington Times Advertising Department. A special international report. Textile industry still faces
barriers in the US market; 2000. http://www.internationalspecialreports.com/europe/00/turkey/22.html
[9] TS. Treasury statistics, 1980–1999. Outstanding external debt profile; 2000. http://www.treasury.gov.tr/yayin/
hazineistatistikleri/3-6.htm
[10] MEF, Monthly Economic Figures. Istanbul Chamber of Commerce, National Income–Investment Incentive Certificates;
2001. p. 2–4.
[11] PMT, Prime Ministry of Turkey. Undersecretary of Foreign Trade Export Promotion Center. Economic outlook economy
in 2000; 2000. http://www.igeme.org.tr/introeng.htm
[12] WT. The Washington Times Advertising Department, a special international report. Energy sector offers large investment
opportunities; 2000. http://www.internationalspecialreports.com/europe/00/turkey/3.html
[13] Pasin S. Improvement of hydroelectric in Turkey and in the World. Energy Worlds 2002;41:46–55 [in Turkish].
[14] Balduk M. Turkish Grand National Assembly. The situation of the textile industry and suggestion for the solutions of the
problems; 2002. http://www.tbmm.gov.tr/komisyon/tekstil/gelen4.htm [in Turkish].
[15] DPT. State Planing Organization, Textile and Apparel Specialist Commission. Eighth five years development plan. Report
no. 2549. OIK: 565; 2001 [in Turkish].
[16] IEA. Energy prices and taxes. Retail prices in selected countries in US dollars/unit; 2002, http://www.iea.org/statist/
key2001/key2001/keystats.htm
[17] Tiris M, Akgun F, Olgun H. Industrial energy conservation activities in Turkey. In: Dincer I, Zubair SM, Al-Farayedhi A,
editors. Proceedings of the workshop on energy conservation in industrial applications, 12–14 February. Dhahran, Saudi
Arabia: Department of Mechanical Engineering, College of Engineering Science; 2000. p. 345–52.
H.K. Ozturk / Energy 30 (2005) 2424–24462446
[18] The Turkish Scientific and Technologic Research Committee, Turkish Technology Development Committee,
ScienceTechnology, Industry Discussion Platform. Energy technologies policies study group report, Ankara, Turkey;
May 1998 [in Turkish].
[19] Hepbasli A, Ozalp N. Development of energy efficiency and management implementation in the Turkish industrial sector.
Energy Convers Manage 2003;44:231–49.
[20] Kalliala E, Talvenmaa P. Environmental profile of textile wet processing in Finland. J Cleaner Prod 2000;8:143–54.
[21] Tang O, Mohanty B. Industrial energy efficiency improvement through cogeneration: a case study of the textile industry in
Thailand. Energy 1996;21(12):1169–78.
[22] UNIDO, United Nations Industrial Development Organization. Textile industry. Output of a seminar on energy
conservation in textile industry; 1992.
[23] Tiwari P. An analysis of sectoral energy intensity in India. Energy Policy 2000;28:771–8.
[24] Mozes E, Cornelissen RL, Hirs GG, Boom RM. Exergy analysis of the conventional textile washing process. Energy
Convers Manage 1998;39(16–18):1835–43.
[25] Deventer HC. Feasibility of energy efficient steam drying of paper and textile including process integration. App Thermal
Eng 1997; 17(8–10): 1035–1041.
[26] Muneer T, Maubleu S, Asif M. Prospects of solar water heating for textile industry in Pakistan. Renew Sustain Energy Rev
2004;1–23.
[27] EIE, Electricity Research Organization . Energy management principle for industry. 2nd ed. vol. I. Ankara, Turkey:
Elektrik Isleri Etud Idaresi Genel Mudurlugu, Ulusal Enerji Tasarrufu Merkesi; 2004 [in Turkish].
[28] IEA, Internatıonal Energy Agency. Energy policies of IEA countries, Turkey. 2001 Review; 2001. http://iea.org
[29] Ozturk HK, Atılgan M, Ikiz Y, Yılmaz Y. Using the geothermal energy of Denizli Kızildere for textile industry.
Renewable energy congress, 12–13 Ekim, Kayseri; 2002 [in Turkish].
[30] Toksoy M. Decision of energy price of geothermal energy for the consumer. Thermodynamic 2000;97:46–54 [in Turkish].
[31] Taner T. Energy management for Turkish industry. MSc Thesis. Pamukkale University, Turkey; 2002 [in Turkish].