Dreams About Clean And Renewable Energy In One Small Municipality In South-Eastern Serbia

In Serbia, there are more than 240 thermo-mineral springs(THM-s). The municipality of Kursumlija covers an area of 952 km², but the number of THM-s is huge (see Figure 1). Also in this area are three official and ten unofficial spas. The indoor temperatures in the spas are between 20⁰C and 68⁰C, and they are valuable for space heating, balneology, greenhouse heating, etc.

But, although this municipality has huge geothermal, solar, and wood waste potential, local governments use dirty energy sources, such as timber, coal, oil, and natural gas. The main goal of renewable energy sources would be to heat households, which would reduce the negative influence of natural gas and oil. In this way, the inhabitants of this municipality would be freed from energy dependence. (Milivojevic et al., 1992; Milojevic and Martinovic, 2005). The average geothermal energy capacity in Serbia is estimated to fall within a range of <100 mW/m² to 120 mW/m².

The elaboration of thermal-mineral waters in Serbia has a long tradition, dating back 150 years. The first scientific book about the connection between geology and thermal mineral-springs was published by Radovanovic in 1897 (Radovanović, 1897).

Figure 1. Position of the research area and the Republic of Serbia in Europe. Credit: Aleksandar Valjarević

Currently, the three main spas in the municipality of Kursumlija are Lukovska, Prolom, and Kursumlijska. Also, we have more than ten unofficial spas with excellent water characteristics and good energy potential.

Serbia also has four independent geological units: in the North, there is Pannonian Basin, in the West Dinarides, in the South-East there is Carpatho-Balkanides, and in the south, the Serbian Macedonian massif. Prolom and Kursumlijska spa belong to the Serbian Macedonian massi, and Lukovska to the Sumadija-Kopaonik belt.

All of these spas have post-volcanism activity (Teofilovic et al.,1972). The average depth of boreholes is between 200 and 300 m. Indoor temperatures vary; in the Kursumlijska spa, we have an indoor temperature of 68⁰C, but an outdoor temperature of 25⁰C. In the hottest spa of Lukovo, we have an indoor temperature of 67⁰C with an outdoor temperature of 35⁰C, while in the Prolom spa, the indoor temperature is 31⁰C and outdoor is 24⁰C. In other springs, we have very similar indoor and outdoor temperatures. Boreholes in the area of the Prolom spa have somewhat lower temperatures, whereas, in the areas of Lukovska and Kursimllijska, temperatures inside the boreholes are higher.  90% of thermal-mineral waters belong to the Calcium-carbonates type, excluding water in Devil city, which is comprised of rare acid water (Filipovic,2003).

Today, excluding medical purposes and tourism, water in two spas, Lukovo and Prolom, is not used enough. Maybe one of the worst examples in all of Europe is the thermal-mineral waters in  Kursumlijska spa, since the spa has not been in function for the last twelve years after it closed in 2006. Streams of thermal-mineral waters flow to the nearest Toplica river, which means the spa loses the equivalent energy of 180TJ/year, as well as 200,000 USD of calculated energy for the electricity. With the help of advanced GIS (Geographical Information System) and after more than two years of collecting data, we estimated the energy potential for the total area of Kursumlija municipality (Valjarevic at al., 2015; Valjarevic at al.,2018).

In this way, we tried to present one of the most likely renewable, as well as the richest, territory in Europe. In this research, we used GIS numerical and geo-statistics methods to estimate energy potential and dispersion (Figure 3).

Figure 3. Indoor temperatures of THM-s in the territory of Kursumlija municipality. Credit: Aleksandar Valjarević

After detailed analysis, we got results and concluded that the biggest potential exists in the North-East edge of the municipality. The total energy in the whole territory is 620TJ/year, or 19.6MWt, which could be enough to heat  500 households or more than 100,000 sq. meters.

Credit: Aleksandar Valjarevic

Furthermore, this area represents only 1% of the territory but produces 25% of the total geothermal energy in comparison with the province of Vojvodina. For numerical analysis, we included elevation of geothermal energy and also used energy dispersion in three dimensions. 12.9 km² can be used for heating and producing electricity since these belts cover an area between 300 and 500 m of elevation. In the economical sense, the municipality can save approximately 700,000 USD per year and reduce the influence of dirty energy sources on municipalities. We even investigated a relatively small area that would be a good example of how Serbia may have neutralized the influence on the import of natural gas and oil (Valjarevic at al., 2018).

These findings are described in the article entitled A GIS-based method for analysis of a better utilization of thermal-mineral springs in the municipality of Kursumlija (Serbia), recently published in the journal Renewable and Sustainable Energy Reviews.

This work was conducted by Aleksandar Valjarević, Danica Srećković-Batoćanin, Dragana Valjarević, and Vesna Matović from the Department for Management of Science and Technology Development, Ton Duc Thang University, Ho Chi Minh City, Vietnam; Faculty of Environment and Labour Safety, Ton Duc Thang University, Ho Chi Minh City, Vietnam, as well University of Belgrade Faculty of Mining and Geology and the University of Kosovska Mitrovica, Department of Mathematics.

References:

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