Analysis of electric power production results in South Serbia: Recommendations for improvement of operation of first mini photovoltaic power plants

Solar radiation in Serbia is for about a third higher than in Middle Europe, which represents a very favorable energy potential. Southeast Serbia is a leading area in this aspect, since the annual average of daily global radiation on a horizontal surface exceeds 4.2 kWh/m2. This paper compares four photovoltaic power plants installed in southeastern Serbia. Analyzes are done based on results from two years of power plant exploitation. The power plants are not located in the same area – there are differences between topography and altitude of their locations, which is also taken into account during analyzes. Photovoltaic modules have different orientation and inclination toward horizontal surface, and their capacity varies from 30-40 kW. The conclusion provides recommendations for improvement of production where it is actually possible

The study of effects of greenery on temperature reduction in urban areas

Urban landscape is largely characterized by high degree of built space, high share of artificial surface material and the reduction of green areas, which leads to changes in the microclimate and the deterioration of thermal comfort in out-door urban space. One of the most important roles of urban greenery is the impact on the reduction of air temperature due to less heating of green space com-pared to paved surfaces and due to tree shading. The paper analyses the influence of urban greenery on temperature reduction. Aim of the study was to measure the difference in warming up of grassy surfaces and paving materials commonly used for public areas and to evaluate the impact of tree shading on the surface cooling during the day. For this purpose, measuring of surface temperatures was performed during the summer months in 2015 in the central city zone of the city of Nis. The measuring included: grass, asphalt as most commonly used paving material, and concrete tiles commonly used for pedestrian areas. Results show the temperature of grass is significantly lower than the temperature of paved surface at any time of day. In the case of paved surfaces, temperature of shaded or partially shaded material is lower than the temperature of surface exposed to sunlight during the whole day, a temperature difference exists even after nocturnal cooling. The results indicate the importance of green areas for cooling of urban spaces, due to their lower warming and surface shading from tree canopy

Urban and architectural character of thermal ambient influences in operation of photovoltaic panels on buildings

This paper presents some basic urban and architectural requirements regarding the installation of solar panels for electricity production on buildings. These requirements are usually design ‒ aesthetic and functional ‒ constructive. However, from the thermal ambient aspect, constructor’s solution is often not in accordance with requirements of architectural and urban planning profession. It is a known fact that thermal environment impacts the yield in the solar panels production. The aim of this paper is to show, based on experience of solar power plant DOMIT, city of Leskovac, Serbia, what is the expected effect in that aspect, in order to choose the optimal solution with regard to the character of the building. The most favorable production have solar power plants built on buildings where the panels on the underside are completely open because they have the best ventilation, and therefore cooling