Energija, ekonomija, ekologija最新文献

{"title":"Pоbоlјšаnjе prеdikciје prоizvоdnjе vеtrоеlеktrаnа u Јužnоm Bаnаtu kоmbinоvаnjеm pојеdinаčnih prоgnоzа pоmоću mоdеlа vеštаčkе intеligеnciје","authors":"Мilicа Kоprivicа, Željko Đurišić","doi":"10.46793/eee21-3.54k","DOIUrl":"https://doi.org/10.46793/eee21-3.54k","url":null,"abstract":"The prediction of day-ahead wind farm production is crucial for optimal unit engagement and minimizing power balancing costs in the power system. Several wind farms which use different models to predict the production have been built in the South Banat region. The basic idea in this paper is to combine the production predictions of each of the wind farms with the production predictions of other wind farms in the region using the artificial intelligence model. This approach has a physical justification given that all wind farms are located in a region with the same wind climatology. Since the total error in estimating production for the day ahead is of interest for planning balancing capacities, this paper analyses the possibility of minimizing cumulative error through the application of artificial intelligence algorithms. The algorithms combine forecasts of individual wind farm models and thus make corrections in estimating the total production of wind farms in this region. The training of the neural network model was performed on the basis of forecasts of individual wind farms for the day ahead and performance. One-year sets of forecasted and realized wind farm productions that were in operation in 2020 were used to train the networks. The developed model of prediction of cumulative wind farm production in South Banat enables the transmission system operator to perform subsequent processing of individual predictions of wind farm production in order to reduce the total error in the assessment of cumulative production.","PeriodicalId":236996,"journal":{"name":"Energija, ekonomija, ekologija","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126120590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pravična tranzicija energetike Srbije – održivost reformi u uslovima nove globalne krize","authors":"Petar Đukić","doi":"10.46793/eee22-3.53d","DOIUrl":"https://doi.org/10.46793/eee22-3.53d","url":null,"abstract":"The accomplished results of the energy transition in Serbia are in big delay, in comparison to the relevant countries in Europe and the world. Energy sector is the biggest anthropogenic factor of air pollution in Serbia, as much as all damaging emissions. Serbian climate action and green agenda have to start from the energetics. The majority of Serbian citizens are aware of that, but there are not enough organised public efforts for the structural changes in the big public companies and institutional system in the energy sector. Regardless how much updated, the environmental standards, programs and the strategies will not be efficient unless we put systematic work of designing one socially acceptable model for structural reform of the energy sector. Energy transition in today’s world is the process that leads to the rapid decarbonisation and “greening” of energy systems, in the way that permanently increases economic performances and energy efficiency, as well as one social sustainable and controlled process of the institutional changes. Serbia belongs to the group of the “leading” countries towards coal participation in electricity power production, as much as in the energy mix. Therefore, transformation and distribution loses, especially those in the electricity sector are unacceptably high. That is why it is necessary to undertake a systematic discussion about basic contents of one just and socially sustainable model of energy transition. Some foreign experiences, especially Czech Hungarian, Polish, Rumanian, Greek and Bulgarian could be useful, but it should not be enough. Large debate needs to be conducted behind the level of political confrontations, including all interested parties. The independent experts, representatives of employed in energy companies, union activists, as much as actual administration and management, citizens depending of energy companies, students and NGOs on the local and national level, all should be included in this dispute. On the level of the national executive authority and legislative power, it should be constituted one advisory body, that could strategically deal with acceptable solutions of just energy transition and its monitoring in Serbia, at list for the next two or three decades.","PeriodicalId":236996,"journal":{"name":"Energija, ekonomija, ekologija","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127027203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Električni automobil sa integrisanim fotonaponskim sistemom","authors":"Vladimir Antonijević, Željko Đurišić","doi":"10.46793/eee20-1-2.160a","DOIUrl":"https://doi.org/10.46793/eee20-1-2.160a","url":null,"abstract":"- The paper deals with the modeling and analysis of the effects of integrating photovoltaic systems into the body elements of electric vehicles. The aim of this paper was to examine the capacities, opportunities and effects of local electricity generation in real electric cars. Given the complex geometry of the vehicle and its mobility, this task posed a relatively complex engineering challenge. A mathematical model in MATLAB software has been developed that enables the estimation of the time diagram of photovoltaic panels production integrated into moving objects of complex geometry. Based on real irradiation measurement data for several locations in Serbia, analyses and calculations of the energy balances of electric vehicles with and without integrated photovoltaic panels in the car body were carried out. The results of the paper show the cost effectiveness for the application of this solution in the automotive industry. In addition to the local production of clean energy, the effects of increasing vehicle autonomy and longer range, less frequent visit to the charging station, less dependency and less impact of vehicles on power system are also achieved.","PeriodicalId":236996,"journal":{"name":"Energija, ekonomija, ekologija","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128001517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vertikalne fasade solitera kao lokacije za instalaciju fotonaponskih panela","authors":"Andreja Stefanović","doi":"10.46793/eee22-2.06s","DOIUrl":"https://doi.org/10.46793/eee22-2.06s","url":null,"abstract":"Fasade solitera predstavljaju alternativnu lokaciju za instalaciju fotonaponskih panela, koji se najčešće postavljaju na krovove objekata. Specifičan prostorni oblik solitera, sa relativno malom površinom osnove u odnosu na visinu objekata, pruža mogućnost iskorišćenja vertikalnih fasada ovih objekata, koje su često u lošem stanju. Fotonaponski paneli postavljeni na ovakvim lokacijama, osim generisanja električne energije, mogu imati estetski i urbanistički uticaj na gradski prostor. U ovom radu je izvršena simulacija generacije električne energije iz fotonaponskih panela, lociranih na vertikalnim fasadama solitera grada Kragujevca, korišćenjem softvera EnergyPlus. Sprovedena je analiza dobijenih rezultata za realne prostorne orijentacije fasada, pri čemu je modelirano i okruženje solitera koje stvara osenčenje fasada, kao što su okolni objekti i visoko drveće. Dobijene godišnje vrednosti generisane električne energije su upoređene sa energijom koje se troši za grejanje ovih građevinskih objekata.","PeriodicalId":236996,"journal":{"name":"Energija, ekonomija, ekologija","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134388662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimalno dimenzionisanje mikromreže sa obnovljivim izvorima energije u Srbiji","authors":"Vladimir Antonijević, Lazar Mlađenović, Goran Dobrić, Mileta Žarković","doi":"10.46793/eee21-4.16a","DOIUrl":"https://doi.org/10.46793/eee21-4.16a","url":null,"abstract":"The paper analyzes the formation of the microgrid in South Banat. The paper contains three scenarios related to determining the size of the distribution area of the part of the electric power system of Serbia that can potentially be powered only from renewable energy sources. Based on real data on the production of four wind farms in Serbia (Čibuk, Kovačica, Alibunar and Košava) for the period January - June 2019 and real consumption data, the first scenario was formed which refers to determining the part of distribution area that can be covered from existing wind farms. In this scenario, with respect to the criteria of uninterrupted power supply, the percentage share of energy from the electricity network was determined for different sizes of distribution area. In order to reduce the share of energy from the electricity network, a new scenario was considered, which refers to the addition of production capacities of solar energy. The analysis of the second scenario showed reduced cumulative intermittency of wind and solar power plants compared to the first scenario. The complementary nature of the sun and wind contributes to a better correlation between consumption and production. The third scenario involves adding storage capacity to the second scenario. A genetic algorithm was applied for the optimal determination of the storage capacity of a microgrid in both grid-connected and islanded modes. A correlation coefficient of production and consumption was formed for each scenario. A complete analysis was performed in order to consider the possibility of forming a microgrid in the part of the Serbian power system near wind farms. This analysis showed a reduction in transmission losses, a reduction in CO2 emissions and better voltage conditions.","PeriodicalId":236996,"journal":{"name":"Energija, ekonomija, ekologija","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134229858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Problematika priključenja vetroelektrana na prenosnu mrežu EMS ad","authors":"Saša Zdravković, Milan Blažić, Branko Šumonja, Marija Đorđević, Julijana Vićovac, Nebojša Đurin","doi":"10.46793/eee20-1-2.044z","DOIUrl":"https://doi.org/10.46793/eee20-1-2.044z","url":null,"abstract":"in 2018 the first connections of wind farms to the transmission network EMS have been realized. In a short period of time, the total of four (4) wind farms were put into operation and, therefore, with engaging a lot of employees, it was necessary to modify and adapt a number of procedures and regulations in order to conclude all the Wind Energy Exploitation Agreements. Due to the stochasticity of the wind phenomenon, the forecast of wind farm production and its relation to the achieved energy production shall be addressed. As the employees of JSC EMS meet for the first time with this type of production capacities, the paper contains real data on meteorological parameters that influence the production of electricity from wind farms. Since all four (4) wind farms are located in the same geographical area, their impact on power flows, operational planning and balancing of the electrical power system shall be analyzed.","PeriodicalId":236996,"journal":{"name":"Energija, ekonomija, ekologija","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132483926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The importance of district heating systems in periods of energy crisis: Case study for the city of Skopje","authors":"Igor K. Shesho, Monika Uler-Zefikj, R. Filkoski, Done J. Tashevski","doi":"10.46793/eee22-2.40s","DOIUrl":"https://doi.org/10.46793/eee22-2.40s","url":null,"abstract":"Nowadays energy crises are characterized by their intensity, i.e. for a short period of time they can cause significant consequences on the economy and overall living. The impacts of energy crisis are mainly reflected indirectly through misbalance in electrical energy production, which is main component and foundation for all socio-economic processes. In addition, the current coincidence of the energy crisis (high price of natural gas) with the heating season reveals and emphasizes the importance of the heating energy. The aim of this paper is to analyse the role, advantages and disadvantages of existing district heating (DH) systems with cogeneration power plants CHP), as an important link in the country power system, especially in times of energy crises. In the analyses as a reference system is considered the DH system in Skopje, Republic of North Macedonia. Assessment for the influence of the fluctuation in heat consumption in the DH system on the power system is performed by using simulation software for energy modelling of the district heating system in Skopje, linked with the data for yearly (hourly basis) electricity consumption. Additional economic assessment is conducted to determine cost competitiveness of DH system with other individual heating technologies available in urban areas. Results reveal that district heating systems with cogeneration power plants in densely populated urban areas are cost optimal heating system and extremely important link in country energy chain, providing energy stability, along with potential consequences in case of longer (un) foreseen interruptions in operation.","PeriodicalId":236996,"journal":{"name":"Energija, ekonomija, ekologija","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133377653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lociranje parcijalnih pražnjenja u energetskom transformatoru primenom UHF tehnike","authors":"Đorđe Dukanac","doi":"10.46793/eee21-2.73d","DOIUrl":"https://doi.org/10.46793/eee21-2.73d","url":null,"abstract":"A specially developed algorithm used in the program in MATLAB in a simplified model of a large power transformer will determine the locations of partial discharges using four UHF sensors by simulating ten real waveforms from a source of partial discharges. Subsequent interpolation of the recorded signals will be performed, in order to obtain the closest possible shapes to the actual waveforms. Actual waveforms were obtained by experimenting with a single UHF sensor in a real large power transformer. The ten signals of the actual shape are mutually different heights of the initial several peaks and different shapes, but still have similar maximum amplitude, frequency spectrum and the prevailing frequency of the most prominent partial discharges. It was important to determine where the actual signal begins, for which a unique calculation procedure was made, and later to accurately determine the differences between the occurrences of the first (reference) peaks of the actual signals at individual sensors. The most favourable threshold value was taken into account when determining the differences in signal arrival times by the method of the first acceptable peak. The deviations in the calculated positions of the sources of partial discharges obtained for 120 randomly selected points in the volume of the transformer tank model will be analysed.","PeriodicalId":236996,"journal":{"name":"Energija, ekonomija, ekologija","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115377597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Directional Ground Overcurrent Protection Setting Calculation in Transmission Network by Using Differential Evolution Algorithm","authors":"Miljana Todorović, A. Savic","doi":"10.46793/eee22-1.60t","DOIUrl":"https://doi.org/10.46793/eee22-1.60t","url":null,"abstract":"The paper presents the procedure of directional ground overcurrent protection setting calculation in the transmission network by using classical calculation procedure and by using an advanced algorithm of differential evolution. To meet the basic requirements of relay protection systems such as speed, selectivity, coordination and sensitivity, the conditions that need to be considered when setting directional ground overcurrent protection are defined. By using the optimization method, the problem was solved in two ways. In the first case, the settings are designed to minimize the total response time of directional ground overcurrent protection to remote-end high-resistance faults, whereas in the second case the settings are designed so that the maximum response time to remote-end high-resistance fault is minimal. The results obtained using the classical approach are compared with the results obtained using the optimization method and the advantages and disadvantages of both approaches are highlighted.","PeriodicalId":236996,"journal":{"name":"Energija, ekonomija, ekologija","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125554869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mogućnost korišćenјa toplotnih pumpi sa otpadnom toplotom iz postrojenјa za prečišćavanјe otpadnih voda kao toplotnim izvorom","authors":"D. Ivezić, M. Živković, Aleksandar Madžarević, B. Pavlović","doi":"10.46793/eee21-1.11i","DOIUrl":"https://doi.org/10.46793/eee21-1.11i","url":null,"abstract":"In the next period, it is planned to build several wastewater treatment systems in major cities in Serbia. Experiences from the facilities currently in operation show that treated wastewater (taking into consideration available flow and temperature) could be a significant source of renewable energy. The paper presents examples of good practice in the use of this energy source by heat pumps in district heating systems in the EU countries. The operation of the wastewater treatment plant in the city of Šabac was analysed and the possibility of its use in the local district heating system was considered.","PeriodicalId":236996,"journal":{"name":"Energija, ekonomija, ekologija","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125711908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}