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In recent years, more attention has been paid to the use of third generation feedstocs for the production of biodiesel. One of the most promising sources of oil for biodiesel production are microalgae. They are unicellular or colonial photosynthetic organisms, with permanently increasing industrial application in the production of not only chemicals and nutritional supplements but also biodiesel. Biodiesel productivity per hectare of cultivation area can be up to 100 times higher for microalgae than for oil crops. Also, microalgae can grow in a variety of environments that are often unsuitable for agricultural purposes. Microalgae oil content varies in different species and can reach up to 77% of dry biomass, while the oil productivity by the phototrophic cultivation of microalgae is up to 122 mg/l/d. Variations of the growth conditions and the implementation of the genetic engineering can induce the changes in the composition and productivity of microalgal oil. Biodiesel from microalgae can be produced in two ways: by transesterification of oil extracted from biomass or by direct transesterification of algal biomass (so called in situ transesterification). This paper reviews the curent status of microalgae used for the production of biodiesel including their isolation, cultivation, harvesting and conversion to biodiesel. Because of high oil productivity, microalgae will play a significant role in future biodiesel production. The advantages of using microalgae as a source for biofuel production are increased efficiency and reduced cost of production. Also, microalgae do not require a lot of space for growing and do not have a negative impact on the global food and water supplies. Disadvantages of using microalgae are more difficult separation of biomass and the need for further research to develop standardized methods for microalgae cultivation and biodiesel production. Currently, microalgae are not yet sustainable option for the commercial production of biodiesel. First of all, the price of biodiesel from microalgae is still higher than the price of diesel due to high production costs. [Projekat Ministarstva nauke Republike Srbije, br. III 45001]

The aim of this study was to evaluate the chemical composition of the back fat tissue of mangalitsa pig and meaty pig breeds and their crosses, and the pigs that were fed with feed that was enriched or unenriched with oil, from the aspect of the production of biodiesel, where the starting material for the fuel would be the fat tissue of pigs. By examining the impact of breed and oil content in feed, it was found that chemical parameters (fat, water, protein, saturated and unsaturated fatty acids) show statistically significant variation under the influence of these factors. The highest fat content (89.39%), which is essential for conversion of fat into biodiesel, was found in back adipose tissue of mangalitsa breed, while the lowest fat content (86.10%) was found in the back fat tissue of meaty breeds and their crosses. Favorable ratio of saturated to unsaturated fatty acids (37.92% : 62.07%), on which some physical properties of the fuel depend, was found in the back fat tissue of pigs that were fed with feed enriched with oil, and the largest proportion of saturated fatty acids, i.e. the most unfavorable fatty acid composition (40.90% : 59.09%) was found in the back fat tissues of pigs that were fed with feed unenriched with oil. The lowest content of saturated fatty acids and water (7.44%), as the key factors that determine the cetane number of the fuel and the fuel production process, indicates that the most suitable raw material for the production of biodiesel is the fat tissue of pigs that were fed with food that contained a certain amount of oil.

In Serbia, the ash from power plants has long been labelled as hazardous waste. With the adoption of the appropriate legislation this ash became secondary raw material with the potential usage. In this paper an analysis of the fly and bottom ash composition, which are disposed of in the power plant “Nikola Tesla A” landfill, is presented. Thirty samples, divided into three sets, were analyzed for trace elements As, Ba, Be, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Ti, V and Zn. The first and second set of samples were taken at the depth of 0.0-0.6 m, from cassette III, at the place of waste discharge (set I) and in the centre of the cassette (set II).The third set of samples was taken from the same cassette spot but at the different depth. The estimated variations in quality within individual sets, as well as the comparison between sets I and II, were done. The repeatability of results by the depth of cassette (set III) was also analyzed. The mixture consisting of 79.4% limestone, 17% clay, 0.5% sand, 0.55% iron ore, 0.55% from steel mill waste and 2% ash from the thermal power plant "Nikola Tesla A" was adopted as the reputable mixture for cement making. For concrete making, the same cement mixture was used but with 2.1% of the same ash material added. The results showed possibility of further fly and bottom ash use as the cement and concrete material.

The paper analyses how a fast advance in technology can ease both discovering and exploitation of alternative energy resources available in space, and at the same time can open new long-term conflicts over supremacy in commercialisation of space resources. The author considers viability of actual and planned projects of members of the prestigious club of “space nations”-the United States, Japan, Russia and the European Union. Global energy demand growth stimulates technologically advanced countries to explore more intensively the technical feasibility and economic viability of renewable energy sources in space. Along with advancement in space technology in the foreseeable future, astro-resources could be used as an alternative or at least a supplement to the existing resource base. The author argues that the increasing space technology ambitions of China, India and, to some extent Iran, create a potential knot of new geopolitical and geoeconomical international conflicts. In conclusion, the author emphasizes that the extraterrestrial sources for the Earth's energy needs will not only stay an important alternative basis for energy security in decades to come, but space itself is likely to become rather a new battlefield of the great powersʼ strategic interests than a part of the common heritage of mankind, equally accessible to all nations.

The main focus of this paper lies with the national laws of three European countries (Germany, Austria and Hungary), as well as the EU law, relating to liability for damage caused by nuclear plant. The aforesaid European countries have enacted legislation prescribing stringent rules on liability of the operators of nuclear plants, meaning that for some forms of legally recognized harm (death, injury, damage to health) the operator incurs liability, even if damage was caused by force major. This type of strict liability, whereby force major is not reason for exculpation, provided that the damage could be related to functioning of the plant, is named absolute liability. In addition, some regimes introduce presumption of causality, when it is more likely than not that damage resulted from the effects of nuclear plants (or ionizing radiation, or secondary nuclear waste materials). The author also analyzes national and European rules on prevention of nuclear and other environmental damage, which includes the creation of the registry of nuclear plants with relevant data on domestic and European operators, the mechanisms of control of the operators, the requirement of preliminary ecological analysis in the construction of new plants, etc. In addition, the author observes differences between nuclear damage in broad and in narrow sense. The former is, in principle, redressed generally, to the extent possible. The latter is commonly redressed individually, to the extent prescribed by statutes.

Three urban redevelopment projects recently undertaken in Europe–Ria 2000 in Bilbao, Spain; Emscher Park in Germany; and Gasometer in Vienna, Austria, are presented and discussed in the paper. All three innovate on three independent levelsculture, economy and urban organization, and provide high quality places to assist their cities and regions to cope with a global competitive environment. All three were also designed to represent the best of the sustainable practice in Europe at the time. In the same time, the basic phylosophy of all three is deeply rooted in creative economies and elaborate their bacis principles. The paper explores their design solution in order to identify the points where creative industries and sustainability meet, and investigates if, and to what extent, they comply with the principles of sustainability. Urban design and physical space are in focus, while other areas are considered as long as they contribute to the design, or reflect a credo that architecture and urban design are among those that play a central role in building cities’ reputation and character. The author argues that all three materialized some of the basic principles of sustainability, by elaborating ideas of genius loci and the relationship between identity and locality. Emscher Park has been the most successful in demonstrating how the brownfield site and devastated area could be transformed into the cultural landscape. Ria 2000 brought in a new interpretation of balance between the man made and natural environments. Gasometer has been least successful, and rather its solutions go after the traditional redevelopment paradigm. На примеру три изведена пројекта, Риа 2000 у Билбаоу, Емшер парк у Рурској области и Гасометар град у Бечу, разматра се релација између креативних економија и одрживости. Иако се три пројекта у стручној јавности сагледавају пре свега као примери обнове у духу нових економија, па се у том смислу и воде расправе, у овом раду је полазиште другачије. Намера је да се пројекти погледају из другог угла и да се њихов однос према одрживости стави у средиште интересовања. Овакво опредељење аутора базирано је у ставу да две филозофије не само да имају додирне тачке, већ се по значајном броју питања преклапају или деле заједничке вредности и опредељења. Са таквим циљем у виду, у раду се дефинише сет критеријума одрживости и спроводи анализа три пројекта. Низ заључака потврђује полазни став, што пред урбанисте и планере ставља нова питања и доноси нове изазове истраживачима и свима онима који се физичким простором и одрживошћу баве.

The economy activity in Serbia is burdened by lots of unfavourable circumstances, including the natural catastrophe so far unseen on this area in May 2014. The unemployment is long-term problem not being resolved with the 'employment policies' but with promotion of investments and achieving the economic growth and development. However, all sectors cannot become the pillars of increase of number and creation of new workplaces. The creators of local economic projections and programmes most frequently use the word 'restructuring'. But in practice, the 'restructuring' demands much more complex and more serious approach so far, above all to public sector of economy. The Serbian energy sector, and above all its public sector, is in front of great challenges deriving from urgent needs of current rehabilitation of flood after effects, from new strategic demands, as well as from European standard. The energy sector is by tradition important determinant of growth and stability of the entire economy. In Serbia, that is especially important considering the state of the capacities and legacy from the past. Modernisation of energy sector implies the application of many new dimensions of sustainability which need to be achieved. Unused renewable sources represent the opportunity for the increase of green investments, sustainable employment, and 'green jobs' in this sector. 'Green economy' and sustainable energy sector represent great opportunity for the future of Serbia. Stabilization and ecologisation of the capacities for the production of thermoelectric energy, increase of the share of renewable sources, and above all the measures of energy efficiency will represent crucial steps and measures towards sustainable energy sector in Serbia. Perhaps they represent true challenge for new construction works, new infrastructure, rehabilitation of schools and hospitals, modernisation of agriculture and tourism, as well as new public and private sector manufacturing capacities.

The importance of school buildings is considerable due to their function, character, purpose, and architectural design, and their refurbishment could lead to significantly better building energy performance. The current research was carried out on select school buildings and is based on a parametric study of the application of energy refurbishment of the thermal envelope (ERTE) and of select passive design systems (PD). The research analyzes the relevant parameters of planning and designing a Trombe wall system (TW), double skin facades (DSF), a green roof (GR), and shading – blinds (BL). In order to determine any possible benefits for increased energy-efficient heating and cooling, models of school buildings were designed using the EnergyPlus software. Climate data which represent a typical meteorological year for the city of Niš were used in the simulation. During modeling, the architectural features of the building were adhered to, as was the layout, the purpose, and the means of using the indoor space. The simulation results indicate that the individual application of the TW, DSF, and GR on the school building models leads to increased energy-efficient heating with decreased energy-efficient cooling. In contrast, the application of BL, independently or in combination with other PD systems, results in the significant increase in energy-efficient cooling. Adequate application of ERTE in combination with TW, DSF, and GR leads to increased energy-efficient heating, while application of ERTE in combination with BL and PD systems leads to the significant increase in energy-efficient cooling. Measures for increased energy-efficient heating and cooling include applying the TW+GR or the DSF+GR system, combined with BL, which confirms that combining numerous PD systems can contribute to significant energy efficiency improvements for the school building models. The application of proper thermal mass and glazing systems significantly increases energy - efficient heating. The application of a TW system, whose thermal mass is either a masonry wall or a 0,25m thick concrete wall, as well as the use of single glazing instead of triple glazing significantly increases energy-efficient heating. The application of a DSF system with an intermediate cavity 0,3 m wide and triple glazing leads to significantly increased energy-efficient heating, compared to applying a DSF system with an intermediate cavity 0.4 m or 0,5 m wide and single glazing. The results confirm that the application of a shading system significantly contributes to increased energy-efficient cooling for the building models. Application of a ventilated TW compared to a non-ventilated one, as well as of a ventilated DSF compared to a non-ventilated one, leads to a significant increase in energy-efficient cooling for the building models. The simulation results offer insight into which parameters provide significant energy efficiency for heating and cooling buildings and confirm the benefits of applying ERTE measures and select PD systems. The applied methodology could be modified, improved, and used in regions with similar climatic characteristics, which would provide a new approach to a decision-making process curbed by limited resources.

Today, most sophisticated numerical methods for predicting building energy consumption are implemented in building energy performance simulation tools. One of the possible ways to improve balance between building energy consumption and occupant thermal comfort in existing buildings is to use simulation-assisted operation of HVAC systems. Simulation-assisted operation can be formulated as a type of operation that implements knowledge of future disturbance acting on the building and that enables operating the systems in such a way to fulfill given goals, which in nature can often be contradictory. The most important future conditions on building energy consumption are weather parameters and occupant behavior and expectations of thermal environment. In order to achieve this type of operation, optimization methods must be applied, i.e. optimal daily operation strategies must be defined for HVAC systems. Methodology to create HVAC system operation strategies on a daily basis is presented in this doctoral dissertation. Methodology is based on using building energy performance simulation software EnergyPlus, data available in short-term weather forecasts, global sensitivity analysis, and for the purpose of this research, developed software. The developed software includes particle swarm optimization method, applied over the moving horizon (planning horizon) thus enabling the use of short-term weather forecasts, with necessary calculations being performed by the chosen simulation tool. Global sensitivity analysis, also performed with the same tool, is used in order to reduce number of input variables for the optimization process. The methodology is applied to real combined-type building in Niš. Objective function of the research is to reduce building energy consumption while satisfying constraints set on thermal comfort in one part of the building. Planning horizon is set to two days, while the resulting strategies are being implemented only on the first day of this horizon. The process repeats for every new planning horizon. The results of the methodology are experimentally verified in real building. The results show that applying this methodology leads to improvement in thermal comfort in most of the premises by using more energy, compared to usual building operation, so it offers a possibility to balance between building energy consumption and thermal comfort. Use of sensitivity analysis as a first step in determining daily building operation strategies, showed that the reduced number of input variables for the optimization would lead to similar thermal comfort and building energy consumption. Since the research was performed for the real building, building energy model calibration was performed in order to make model accurately reproduce the behavior of the real building.

U radu se daje osvrt na najbitnije razlike u nacionalnim regulativama koje definišu oblast energetske efikasnosti zgrada, u Srbiji, Makedoniji, Crnoj Gori i Albaniji, dakle na tržištima za koje je objavljen softver „KnaufTerm2“, u verzijama programa prilagodjenim lokalnim osobenostima, i to sa aspekta energetske sertifikacije, dozvoljenih vrednosti koeficijenata prolaza toplote i tretmanu linijskih transmisionih toplotnih gubitaka. The paper provides an overview of the most important differences in national regulations that define the area of energy efficiency in buildings, in Serbia, Macedonia, Montenegro and Albania, countries for which software "KnaufTerm2" is released, in versions adapted to local characteristics, in terms of energy certification, allowable values of the coefficient of heat transfer and the treatment of linear transmission heat losses.