The way citizens perceive air quality has a huge impact on the public's willingness to contribute agendas that promote a sustainable future. Consequently, the scientific community wonders do the ...sudden and short-term shifts in air quality (such as one caused by the COVID-19 pandemic) have the potential to induce long-term changes in community behavior. This study is based on the interpretation and analysis of a facultative survey administered to the student population of a medium-sized university city in the Balkans. The study's goal is to identify the types and strengths of factors that influence students' perceptions of air quality. In this regard, six classification algorithms were compared in order to select the one with the best fit between students' demographics, traveling habits, and air quality perception. Individual variable influence revealed that Weekly lectures attendance and Distances students travel determine the perception of air quality more than Gender and Permanent place of residence. According to the study, potential commuting reorganization should target those living 2-4 km from the faculty building. Students who regularly attend lectures are likely to be willing to rely on better-organized public transport. Those who do not, will generally contribute the initiative once the positive effects are evident.
This paper shows the thermal energy audit of the kindergarten "Zeka", located in the territory of the city of Kragujevac, Serbia. Data of the analyzed building, with an emphasis on the heating ...system, as well as the climate conditions of the location are shown. Analysis of the thermal energy use, done by implementing a software package "URSA-građevinska fizika 2", shows that the analyzed building belongs to the "G" energy efficiency level, which indicates that the heat transfer coefficients are not in the range defined by the Rule book of energy efficiency for buildings. Consequently, the energy conservation measures for increasing the efficiency of thermal energy use are proposed. Besides, for each measure, the techno- economic analysis was done, which includes determination of the investment costs, as well as the payback period. By implementing the appropriate measures in the analyzed building, it was concluded that thermal energy savings of almost 79% can be achieved.
Educational buildings have a significant share in the total number of buildings of public sector. Also, significant part of energy consumption belongs to these buildings. There are 15 kindergartens ...that are under 2 preschool institutions. Their specific annual heat consumptions are from 79.42 kWh/m2 to 491.52 kWh/m2 (from 106.02 kWh/m2 to 325 kWh/m2 for objects connected to the district heating system). The average specific annual heat consumption is about 22% more than the consumption in neighboring countries. Most kindergarten buildings were built in the '70 and '80s of the last century and do not have adequate thermal insulation. Based on the defined methodology, specific annual heat consumption of these buildings has been analyzed, priorities for reconstruction have been defined and measures for improvement of energy efficiency have been proposed. Conducted case study of implementing the proposed measures at 'Ciciban' kindergarten showed that savings could be from 36% to 58% in heat consumption.
The food industry uses a considerable amount of energy and that amount has been constantly growing with further developments in the sector. The growth of the milk processing industries with the ...production of dairy products has followed the trends in the food industry in general. The authors made a systematization of the literature data on the most common energy efficiency opportunities (measures) in diaries. Authors also present a methodology for conducting an energy audit in dairies based on ISO 50002 which includes a multi-criteria analysis for ranking energy efficiency opportunities. The proposed methodology was applied to a case study dairy in central Serbia. Taking into account interactions between opportunities, implementation of the proposed energy saving opportunities can ensure 11-15% energy savings for electricity and 20-23% of heat energy annually.
The costs related to the operation of street lighting can be significant expenses for municipalities; therefore, it is very important to take advantage of opportunities for improving energy ...efficiency. In this paper, the authors studied the effects of the implementation of energy efficiency measures in a street lighting system. Different scenarios, including replacing luminaires, replacing inefficient lamps, and installing a dimming control system, are analysed. The model includes a detailed analysis of the techno-economic characteristics of both LED street luminaires and LED corn bulbs available on the market. The results show that the replacement of low-power, high-intensity discharge lamps with LED corn bulbs is an economically favourable solution that provides desirable economic project parameters with relatively low investments. Moreover, in the case of a relatively low price of electricity for street lighting, it is the preferable solution in most scenarios.
This paper focuses on the implementation of air-water heat pumps used to provide heating for households instead of electric boilers. The paper proposes a methodology for determining the quantity of ...energy used for heating based on the data collected from electricity bills. In addition, the simulations conducted in a selected software can provide insight into the amount of energy loss based on the constructional characteristics of an object. The proposed methodology was tested through a case study. The results indicate that the selected household can save about 60% of electricity currently consumed. Financially speaking, it is reasonable to expect that the electricity costs can be reduced by three times and that the payback period of the investment would be about four years for this household.
This paper examines the potentials of saving electric energy in school lighting by replacing the existent systems of lighting with more adequate ones which are based on light-emitting diode ...technology. Our primary goal is to present the methodology used in this analysis since it can be used to determine potential savings in lighting systems of any public building. We have performed the detailed analysis of nine high schools located in Kragujevac, Serbia. The first step was to collect the data about the numbers and types of systems utilized, as well as about the habits of their users. This has revealed the share of electricity consumption for lighting in total electricity consumption. The replacements for each existent light source have been proposed taking into consideration the projected value of light flux depending on the purpose of each room. The calculations of potential savings through the replacement of lighting systems have been conducted taking into consideration not only the savings in electric energy but also the savings made through the maintenance cost reduction. Based on the results, the potential savings range from 53-62% while the payback period for the analysed schools is about four years in average.
The use of renewable energy sources for electricity generation in the Western Balkan countries is analyzed in this review paper. Since those countries are part of EU or intend to be, data for Western ...Balkan are also compared with data for EU-28. The first part of the paper presents a brief overview of main promotion mechanism for electricity generation from renewable energy sources. As a dominant support policy, the feed-in tariff is more elaborated as an incentive measure and a de?tailed overview of the amount of tariffs and quotas for dominant technologies in the Western Balkan countries is presented. Furthermore, the current state of installed capacities and annual productions of three particular renewable electricity technologies (small hydro power, wind power, and solar photovoltaic) are analyzed in detailes. Based on presented data, there is a discussion and consideration of the impact of incentive measures on the electricity market and power production from renewable sources.
he paper proposes a methodology for defining the optimal solution for the integrated usage of cogeneration and rooftop photovoltaics. The purpose is to minimize CO₂ emissions in industrial plants. ...The methodology is founded on the integral use of energy audit techniques (analyzing energy and material flows in a production process and the dependence of electricity and heat consumption on a production volume) and mathematical optimization (linear programming). In accordance with the obtained consumption profiles, technical limitations, and legal regulations, the potential for installing rooftop photovoltaic (PV) panels at appropriate locations and the implementation of appropriate cogeneration technologies were analysed. The proposed methodology was tested on a local margarine production facility. The integrated application of cogeneration (gas engines) and photovoltaics can reduce the current CO₂ emission by 56% if PV panels are installed on the entire accessible rooftop surface, i.e. up to 44.5% if 150 kW PV panels are installed as the new national regulation proposes.
Reducing carbon dioxide emissions and achieving climate neutrality is one of the main challenges nowadays. In this regard, the transition from fossil fuels to renewable energy sources is the goal of ...energy planning in various countries worldwide. The Republic of Serbia announced a draft ntegrated National Energy and Climate Plan of the Republic of Serbia for the period 2030 with the projections up to 2050, in response to both the global aspiration and the Paris Agreement. Yet, since cities utilize more than 75% of primary energy globally, they should be considered when it comes to long-term energy planning at the national level. Achieving climate-neutral cities requires time and extensive analysis of energy potential. This paper aims to implement a SWOT analysis of planning the future energy system, with a case study of the city of Kragujevac. The paper outlines all the benefits and factors that can help stakeholders on the road to a climate-neutral city and any potential drawbacks. The utilized SWOT analysis was done in accordance with all available data and it results in the presentation of current energy needs and an insight into possible future directions of energy development of the City of Kragujevac concerning national and local energy policy-