THERMAL SCIENCE

International Scientific Journal

WOOD FUELS CONSUMPTION IN HOUSEHOLDS IN BOSNIA AND HERZEGOVINA

ABSTRACT
The paper shows research results for the consumption of all types of wood fuels in the households in Bosnia and Herzegovina and its entities in 2015. The research was conducted in the period from March 15th to August 26th, 2016 in 109 cities/municipalities in the entire Bosnia and Herzegovina. Complex methodological approach was used for conducting the research, which required field research on the sample of 8,602 households on the entire territory of Bosnia and Herzegovina as well as adequate statistical processing of the obtained data pursuant to the high statistical standards. Research results show that in 2015, 5.4 million m3 of firewood, 81,656 tones of wood pellets, and 6,780 tones of wood briquettes were consumed in the households in Bosnia and Herzegovina. Total expenses of households necessary for the supply of wood fuels in Bosnia and Herzegovina in 2015 were 239.8 M€, with the largest share of firewood (226.8 M€), followed by wood pellets (11.6 M€), and wood briquettes (720.9 thousand €). Average firewood consumption per household in Bosnia and Herzegovina is 6.43 m3. Compared to the surrounding countries it is on the level of Slovenia (6.5 m3 per household), less than in Serbia (7.3 m3 per household) and more than in Montenegro (5.49 m3 per household). Average consumption of energy from firewood expressed in kWh/m2 of the heated surface was 252.7 kWh, which is significantly higher than the average in the EU. One of the reasons for such high consumption of wood energy per 1 m2 of the heated surface is the fact that only 36.1% of the households using solid fuels have thermal insulation on their residential facilities.
KEYWORDS
PAPER SUBMITTED: 2017-01-02
PAPER REVISED: 2017-01-27
PAPER ACCEPTED: 2017-02-08
PUBLISHED ONLINE: 2017-03-03
DOI REFERENCE: https://doi.org/10.2298/TSCI170102034G
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2017, VOLUME 21, ISSUE 5, PAGES [1881 - 1892]
REFERENCES
  1. . After Serbia, research of wood fuels consumption was carried out in Montenegro in the period 2011-2012. This research also showed that actual consumption of wood fuels was significantly higher than the officially registered consumption. According to
  2. actual consumption of firewood in households in Montenegro was 5.1 times higher than the officially recorded consumption in 2011. During 2014, research of wood fuels consumption was conducted on Kosovo as well. According to
  3. , total consumption of firewood on Kosovo is about 2.05 million m3. The issue of balancing the consumption of woody biomass and its potentials has been dealt with other authors in Europe as well. According to
  4. biomass and renewable waste, with a share of 64.2% of primary renewable energy production, is the most important energy source in the EU. However, utilization of renewables in energy production and consumption differs across EU countries and is significantly influenced by various factors. Using Slovakia as an example, almost 83% of all resources used in Slovakia originated in forest biomass, 16.1% were from industry waste, and only 1% came from used paper. On the other hand, over 84% of resources were used industrially, while nearly 16% were used for energy purposes
  5. . 2. Scope and objective of the work The main scope of researches is wood fuels consumption for energy purposes of households in Bosnia and Herzegovina which include heating, food preparation, hot water, brandy distilling, meat smoking, and other purposes. Research objective is to identify the consumption level of all wood fuel types which are used in the households in Bosnia and Herzegovina by applying internationally recognized methodology. Based on such obtained results, consumption of wood energy per 1m2 of the heated surface will be calculated in order to make adequate conclusions and give recommendations to the decision makers in order to adopt measures for increasing the efficiency of wood fuels use in the households in Bosnia and Herzegovina. 3. Used methodology Considering the fact that Bosnia and Herzegovina does not have reliable statistical data on the production and consumption of wood fuels and that numerous studies and papers with the topic of woody biomass were based on the assessment of experts based on official statistical and other data published by certain institutions and organizations, the need to conduct a comprehensive research emerged with the purpose to observe actual consumption and thus participation of wood based energy in the total balance of final energy consumption. The paper used WISDOM methodology defined by the FAO organization
  6. . As the basis for determining the sample for interviewing of households were used the preliminary results from the census conducted in 2013. This sample could include only those households that use solid fuels for heating. In this regard, it was necessary to do the research and collect data on the number of households in all cantons and mesoregions that use other fuels for heating, such as: electricity, gas and fuel oil, and the number of households that use district heating systems. For those purposes, data from all relevant fuel suppliers in Bosnia and Herzegovina were collected through questionnaires. On the basis of thus collected data on the total number of households in Bosnia and Herzegovina in accordance with the census (1,163,387 households), those households that use other fuels for heating were deducted in order to obtain the number of households that use solid fuels such as wood, coal, briquettes, pellets, or combined fuels (fig. 1). The same methodological approach was used in the research of wood fuels consumption in Serbia in 2010, in Montenegro in 2013 and in Macedonia in 2016. Fig. 1. Methodology for determining the number of households which use solid fuels for heating purposes in Bosnia and Herzegovina
  7. Number of households which used the stated fuels was obtained from the District heating plants
  8. , Electric Power Industry
  9. and Petroleum distributors in Bosnia and Herzegovina
  10. representing the number of active households which used the stated fuel forms in the period in which the research was conducted. Using the above mentioned methodological approach (fig.1), the total number of households which used solid fuels (wood fuels and coal) for heating in Bosnia and Herzegovina in 2015 was calculated to 860,228. Thus defined sample was a starting point for defining the size of the sample for interviewing of households. The sample was 1% of the total number of households which use solid fuels, i.e. 8,602 households. After determining the sample, the following methodological steps were made: - to determine the sample size in some cantons, mezoregions and the District of Brčko, was used the same percentage as each canton/mezoregion/District of Brčko had in the total number of households according to the last census in Bosnia and Herzegovina. The total number of 8,602 households in the sample was multiplied by that percentage and so the sample for each canton/mezoregion/district was obtained. - sampling of the number of households in particular towns/municipalities within the cantons/mezoregions/district was done in the same way. Number of households in the sample in certain towns/municipalities within cantons/mezoregions/district was determined based on a percentage share of the number of households in that town/municipality in the number of households at the level of a canton/mezoregion/district. - division of such sampled households into "urban households" and "other households" was based on a share of those two categories (urban and other) in the total number of households at the level of town/municipality. For conducting the field research, 33 interviewers were selected for the entire Bosnia and Herzegovina. For the Republic of Srpska, which is divided into 6 mezoregions (Prijedor, Banja Luka, Doboj, Bijeljina, East Sarajevo and Trebinje), 12 interviewers were selected. In the Federation of Bosnia and Herzegovina, which is divided into 10 cantons, 21 interviewer was selected, and one in the District of Brčko. Households were interviewed between March 15th and April 22nd 2016 in 109 cities/municipalities in the entire Bosnia and Herzegovina, i.e. in its two entities, the Republic of Srpska and the Federation of Bosnia and Herzegovina, and the District of Brčko. Interviewing was conducted in urban settlements, and in at least two larger other settlements in every city/municipality. Survey was conducted in such a manner that interviewers visited households and applied the method of direct interviews (face-to-face). A total of 8,500 households were interviewed for the entire Bosnia and Herzegovina, as follows: households in urban settlements: 3,912 and households in other settlements: 4,588. Compared to the defined sample, there were 102 interviewed households less. The main reason was the lack of cooperation in some cities. However, despite of this, the number of 8,500 interviewed households is fully representative for conducting the analyses on wood fuels consumption in households in Bosnia and Herzegovina since it represents nearly 1% (0.99%) compared to the number of households that use solid fuels.1 Spatial distribution and size of strata for interviewed households by some mezoregions/cantons/district are given in fig.2. Fig. 2- Spatial distribution and size of strata for interviewed households by mezoregions, cantons and district in Bosnia and Herzegovina After interviewing and entering the data into the web application, the entered data were checked, logical control of consumption in physical measurement units per m2 of heating surface was conducted, 1 Sample and its scope are statistically representative for the conducted research in households using only solid fuels for heating purposes (860,228). In 2015, Agency of Statistics of Bosnia and Herzegovina conducted the research on consumption of all types of energy in households at the level of B&H (1,163,387) on a sample of 7,083 households. and then the data were processed, systematized and calculated from the level of a sample to the level of a whole. Data obtained using the above described methodology are used for creation of wood fuel energy balance for 2015 for Bosnia and Herzegovina. Data obtained for some types of fuels needed to be calculated into cubic meters of the compact wood volume, while some other fuels needed no further calculation. Wood fuels for which the data on production and consumption were obtained in stacked m3 or bulk cubic meters, were converted into solid m3 using conversion factor 0.69. 4. Research results and discussion Current situation on wood fuels market in Bosnia and Herzegovina is characterized by the fact that the following types of wood fuels are used for the purpose of heating households: firewood, wood pellets, wood briquettes, logging residues and residues from sawmills. Consumption of wood fuels in households in Bosnia and Herzegovina The stated statistical indicators of the number and structure of households are significant for the analysis of fuel consumption for own purposes (heating, food preparation, etc.). Results of the survey showed that 11% of the total number of households in Bosnia and Herzegovina used district heating system, 9% used electricity, 5% used gas and 1% used heating oil for heating purposes in 2015. The largest number of households (74%) used solid fuels such as firewood, coal, wood briquettes, wood pellets, logging residues, residues from sawmills and combinations of solid and other fuels (fig. 3). Fig. 3. Share of certain fuel types for heating households in Bosnia and Herzegovina in 2015, Sources:
  11. ,
  12. ,
  13. Participation of certain fuel types for the purpose of heating households varies in different regions in Bosnia and Herzegovina. Results of the questionnaires
  14. indicate that the households in 2105 used 27 different combinations of fuels for heating purposes. Fig. 4 shows the share of households with particular fuel combinations on the level of the region in Bosnia and Herzegovina. Fig. 4. Presence of certain fuel types for heating households in Bosnia and Herzegovina in 2015
  15. The main conclusion that can be drawn based on this overview in fig.4 is that firewood individually or combined with coal is dominantly present in all the regions in Bosnia and Herzegovina. Combinations of firewood with other fuels (gas, electricity, heating oil, briquettes, etc.) are present in practice, however with a small share of such households in the total number of households in Bosnia and Herzegovina. Results of the participation of certain types of solid fuels on the level of Bosnia and Herzegovina are presented in fig. 5. Data from fig. 5 show that 70.3% of households, which used solid fuels for heating, use firewood, while the combination wood/coal is present in 23.2% of households. Fig. 5. Participation of certain types of solid fuels for heating households in 2015 in Bosnia and Herzegovina
  16. Total consumption of wood fuels in households in Bosnia and Herzegovina in 2015 is given in tab. 1. Data in tab. 1 are structured as to show consumption of certain wood fuels in households at the level of Bosnia and Herzegovina and its entities. Table 1. Wood fuel consumption in households in Bosnia and Herzegovina in 2015 Urban/ other settlements Type of wood fuel Number of households that use wood fuels Measurement unit Total consumption of wood fuel in households (measurement unit) Total expenses of households for supply of wood fuels (€) BOSNIA AND HERZEGOVINA TOTAL Firewood 839,296 m3 5,398,022 226,822,003 Slabs from sawmills 9,602 m3 26,269 603,524 Wood pellets 17,363 tonnes 81,656 11,559,347 Wood briquettes 3,014 tonnes 6,780 720,890 Logging residues 4,072 m3 9,050 115,185 Sawdust 1,425 tonnes 1,098 21,316 REPUBLIC OF SRPSKA TOTAL Firewood 319,285 m3 2,317,308 88,730,477 Slabs from sawmills 3,751 m3 16,152 295,765 Wood pellets 4,094 tonnes 22,217 3,090,210 Wood briquettes 2,750 tonnes 6,323 674,854 Logging residues 3,188 m3 6,083 29,826 Sawdust 1,321 tonnes 1,087 20,889 FEDERATION OF BOSNIA AND HERZEGOVINA TOTAL Firewood 497,139 m3 2,937,340 133,153,512 Slabs from sawmills 5,693 m3 12,339 285,220 Wood pellets 12,383 tonnes 55,566 7,903,909 Wood briquettes 264 tonnes 457 46,036 Logging residues 751 m3 2,834 84,069 Sawdust 104 tonnes 11 427 DISTRICT BRČKO TOTAL Firewood 22,872 m3 143,374 4,938,014 Slabs from sawmills 483 m3 1,427 22,539 Wood pellets 886 tonnes 3,873 565,228 Logging residues 133 m3 133 1,290 Source:
  17. , Calculations: Glavonjić B. Total consumption of wood fuels for energy purposes in households in Bosnia and Herzegovina in 2015 was as follows: firewood 5.4 millions m3, wood pellets 81,656 tonnes, wood briquettes 6,780 tonnes, slabs from sawmills 26,269 m3, sawdust from industry 1,098 tonnes and logging residues 9,050 m3. Total expenses of households necessary for supply of wood fuels in Bosnia and Herzegovina in 2015 were 239.8 M€, including the largest share of firewood (226.8 M€), and then follow wood pellets (11.6 M€) and wood briquettes (720.9 thousand €). According to the survey results, wood fuels are mostly purchased from timber merchants who represent the main suppliers of all types of wood fuels in Bosnia and Herzegovina. About 75% of the total amount of firewood purchased by households in Bosnia and Herzegovina, the Federation of Bosnia and Herzegovina (74.7%) and the Republic of Srpska (75.0), was purchased from timber merchants, and in the District of Brčko it is 62.9%. Supply of firewood from private or state forests is much lower than the one from merchants, and does not exceed 13.7%. In the District of Brčko, large amounts of firewood are purchased from fuel storages (16.6%). One of the characteristics of wood fuels supply in Bosnia and Herzegovina is the fact that sawmills became sellers of wood briquettes and pellets although they do not produce these types of fuel. This is the result of various compensation deals, which means that sawmills deliver sawdust and slabs to the factories that produce briquettes and pellets, and in return they receive briquettes and pellets which they further sell to households. In some sawmills, there are small presses where briquette is produced out of sawdust, so such sawmills are producers of wood briquettes at the same time. Timing of purchase of firewood compared to the beginning of the heating season is an important factor in firewood consumption. Review of households according to the timing of purchase of firewood relative to the beginning of the heating season is given in fig. 6. Fig.6. Time period in which households purchased firewood compared to the beginning of the heating season in 2015
  18. The largest number of households in Bosnia and Herzegovina purchased firewood in 2015, 2 to 3 months before the heating season (37.5%), and then follow those households that purchased firewood 4 to 6 months before the heating season (28.5%) and those that purchased it right after the end of the previous heating season (18.2%). Results of the conducted field research show that in the Federation of Bosnia and Herzegovina, the largest number of households purchased firewood 4 to 6 months before the heating season, then follow households which purchased it 2 to 3 months before the heating season and those which purchased firewood right after the end of the previous heating season. In the Republic of Srpska, the largest number of households purchased firewood 2 to 3 months before the heating season (45.4%), then follow households that purchased it up to 1 month before the heating season (15.8%) and those that purchased firewood 4 to 6 months before the heating season (14.8%). In the District of Brčko, the largest number of households (51.7%) purchased firewood 2 to 3 before the heating season. Data on attitudes of households in Bosnia and Herzegovina on what type of wood is the best to be used for heating are given in fig.7. Fig.7. Attitudes of households in Bosnia and Herzegovina on the optimal use of wood for heating (2015)
  19. At the level of Bosnia and Herzegovina, total of 44.8% households, compared to the number of households that use solid fuels, consider dry wood as the best for heating, especially the one that stayed for a year or more. In the Federation of Bosnia and Herzegovina, 47.6% of households have the same attitude, and in the Republic of Srpska 40.8% households share the same attitude. In the District of Brčko, there are 37.7% of households with this attitude. Comparative analysis of the data on fig.6 and fig.7 shows that households which consider that it is the best to use dry wood for heating (44.8%) purchase the wood at the time with sufficient period for the wood to get air-dried, in terms of the beginning of the heating season. When it comes to the most frequent purposes for which firewood is used in the households in Bosnia and Herzegovina the results of the survey show that firewood is the most frequently used for heating and food preparation (fig. 8). Results of the field research and the questionnaire have shown that 53.5% of total households which use solid fuels in Bosnia and Herzegovina use firewood for heating and food preparation, in the Federation of Bosnia and Herzegovina 48.7%, in the Republic of Srpska 60.9%, and in the District of Brčko 58.5%. Types and characteristics of heating appliances that used in the households in Bosnia and Herzegovina have an important role in consumption and efficiency of combustion of firewood. Results of conducted survey shown that the most frequent appliance for combustion of wood fuels in Bosnia and Herzegovina in 2015 were wood and coal burning stoves. 422,799 households or 49.2% of the total number of households using solid fuels used these appliances. In the Federation of Bosnia and Herzegovina, 211,702 households (41.1%) use this appliance, 196,194 households (61.1%) in the Republic of Srpska and 14,907 households (61.5%) in the District of Brčko. Fig. 8. Purposes for which firewood is used in households in Bosnia and Herzegovina
  20. The second most frequently used appliances were wood burning stoves in all entities except in the District of Brčko, where the second most frequently used appliances are boilers using solid fuels (18.9%). Other types of appliances are used significantly less than the previously mentioned. Households by the age of the most frequent types of appliances used for wood fuels combustion in households in Bosnia and Herzegovina is given in tab.2. Table 2. Households by the age of the most frequent types of appliances used for wood fuels combustion in households in Bosnia and Herzegovina in 2015 Area Age in years Wood and coal burning stove Wood and coal burning stove, for central heating Wood burning furnace Wood and coal burning furnace, for central heating Boiler using solid fuels (coal, wood, briquette) Tile stove Bosnia and Herzegovina 1-5 124,435 23,212 70,580 29,991 28,962 65 6-10 188,253 28,858 67,823 29,334 28,947 - 11-15 86,333 5,526 23,452 11,037 10,712 125 16-20 31,008 1,628 9,308 2,731 3,680 195 21 and more 18,520 1,394 10,449 3,694 1,829 629 Source
  21. In Bosnia and Herzegovina and its entities, the Federation of Bosnia and Herzegovina and the Republic of Srpska, the most frequently used appliances are wood and coal burning stoves 6 to 10 years old, while in the District of Brčko the most frequent are those 1 to 5 years old. In 41.9% of households at the level of Bosnia and Herzegovina there are wood and coal burning stoves 6 to 10 years old, in the Federation of Bosnia and Herzegovina in 47.7%, and in the Republic of Srpska in 36.3% of households. In the District of Brčko, this type of appliance is mostly 1 to 5 years old, in 41.4% of households that use solid fuels for heating. Graphic presentation of distribution of households depending on the age of wood and coal burning stoves at the level of Bosnia and Herzegovina and its entities is given in fig.9. Note: B&H-Bosnia and Herzegovina; FB&H-The Federation of Bosnia and Herzegovina; RS-The Republic of Srpska Fig.9. Households by age of wood and coal burning stoves in Bosnia and Herzegovina and its entities in 2015
  22. In Bosnia and Herzegovina, 41.9% of households use 6 to 10 years old wood and coal burning stoves. In the Federation of Bosnia and Herzegovina, 47.7% of households use this type of appliance 6 to 10 years old, 32.7% of households in the District of Brčko and 32.3% in the Republic of Srpska. Pellet burning furnaces are appliances of the new generation and therefore they are mainly 1 to 2 years old in households that use these appliances for heating. This refers to the households in all areas in Bosnia and Herzegovina. Boilers that use solid fuels for central heating are mainly 1 to 5 years old in the Federation of Bosnia and Herzegovina, 41.8%. In the Republic of Srpska, these boilers are mainly 6 to 10 years old (37.1%), and in the District of Brčko 11 to 15 years old (32.0%). At the level of Bosnia and Herzegovina, they are mainly 1 to 5 years old, in 39.7% of households. Average consumption of energy per 1m2 of the heated surface in households which use firewood in Bosnia and Herzegovina Average firewood consumption per household in Bosnia and Herzegovina in the amount of 6.43 m3. Compared to the surrounding countries it is on the level of Slovenia (6,5 m3/households), less than in Serbia (7.3 m3/households) and more than in Montenegro (5.49 m3/households)
  23. . Average firewood consumption in households depends on several factors, the following of which are highlighted: size of the heated surface, presence of thermal insulation on the heated facilities, age of windows and doors, possession of insulated glazing on the windows, time of wood purchase compared to the beginning of the heating season and type and age of the appliances. Concerning households in Bosnia and Herzegovina, results of the calculations of the average consumption of wood energy expressed in kWh per 1 m2 of the heated surface are presented in the following text. Size of the heated surface in the households using solid fuels for heating was the starting point in these calculations. Total heated surface in the facilities of the households which used solid fuels for heating in 2015 was 59.6 million m2 on the level of Bosnia and Herzegovina
  24. . Calculation results show that the average consumption of energy from firewood per 1 m2 of the heated surface was 252.7 kWh on the level of Bosnia and Herzegovina in 2015. Having in mind the magnitude of wood energy consumption, it general conclusion can be made that firewood in households is used inefficiently because the average consumption is significantly higher than the average on the level of the European Union
  25. . One of the reasons for such a high consumption of wood energy per 1 m2 of the heated surface is the fact that a small number of households possesses thermal insulation on their facilities. Results of the conducted research show that on the level of Bosnia and Herzegovina, there are 310,731 households or 36.1% that use solid fuels and have thermo-insulation. Among them, 15,575 facilities are up to 5 years old, 43,442 are 6 to 10 years old, 80,910 are 11 to 20 years old and 170,804 facilities are more than 20 years old. Of the total number of households that use solid fuels for heating, 549,497 or 63.9% have no thermo-insulation. Among them, 11,798 facilities are up to 5 years old, 39,094 are 6 to 10 years old, 94,150 are 11 to 20 years old, and 404,455 facilities are more than 20 years old. Based on these data it can be concluded that in Bosnia and Herzegovina and its entities prevail households with no thermo-insulation on their facilities. According to this parameter, the best situation is in the Federation of Bosnia and Herzegovina, where there is 44.1% of households that use solid fuel with thermo-insulation on their facilities. In other entities, situation is significantly worse. In the Republic of Srpska there are 23.4% households with thermo-insulation on their facilities and 35.1% in the District of Brčko. 5. Conclusions Results of the conducted research show that firewood individually or combined with other fuels is the main energy-generating product used for heating purposes in the households in Bosnia and Herzegovina. Out of the total number of households in Bosnia and Herzegovina, 74% or 860,228 households use solid fuels for heating purposes. Out of this, 70.3% of the households use only firewood, 23.2% use wood combined with coal and 3.3% use firewood combined with other fuels. Needs of such a high number of households for firewood in 2015 were on the level of 5.4 million m3 or in average 6.43 m3/household. Results of the performed calculations show that the consumption of wood energy per 1 m2 of the heated surface is 252.7kWh, which is not satisfactory from the aspect of efficient use of firewood. Since firewood is the wood fuel with the highest share in the consumption of wood energy, one of the reasons for its big consumption is the time of purchase compared to the beginning of the heating season. Research results show that 51.8% of the total number of households using firewood purchase it in the period from 2 weeks to 3 months prior to the beginning of the heating season, which is considered to be inefficient purchase from the aspect of efficient use of firewood. The second reason is the fact that very few households have thermal insulation on their facilities. Out of the total number of households that use solid fuels for heating, 549,497 or 63.9% have no thermo-insulation. References
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