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The Simultaneous Effect of the Operating Temperature and Solar Radiation on the Efficiency of Photovoltaic Panels / Jednoczesny Wpływ Temperatury Pracy Oraz Promieniowania Słonecznego Na Wydajnosc Ogniw Fotowoltaicznych

Abstract

The proper designing of PV systems requires the use of advanced building energy simulation techniques. It allows to design the best position of the PV array, as well as the right quantity of produced energy in different cases. On the other hand the PV efficiency is not only a constant value but changes according to temperature and solar radiation. This paper is devoted to estimate the simultaneous effect of both weather factors on PV efficiency. The task was achieved by numerical simulation and ESP-r software. Computer simulations have been carried out with the use of the Typical Meteorological Year data for Warsaw (52°N 21°E). The greatest influence of temperature on the efficiency of solar energy conversion was observed for crystalline silicon cells. The influence of the boundary conditions assumed in the study is ignored for amorphous silicon cells in the summer period and regardless of the material type in the winter period.

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The Statistical Analysis of Relation between Compressive and Tensile/Flexural Strength of High Performance Concrete

statistical analysis of design methods efficiency in determining shear capacity of reinforced concrete beams, Proceedings of the 11th International Probabilistic Workshop, Brno, 2013. 14. S.S. Shapiro, M.B. Wilk., An analysis of variance test for normality, complete samples., Biometrica, vol.54, Great Brittan, 1965.

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Seismic Evaluation of Mixed Steel and RC Columns in Hybrid High-Rise Buildings

Abstract

The growth in high-rise building construction has increased the need for hybrid reinforced concrete and steel structural systems. Columns in buildings are the most important elements because of their seismic resistance. Reinforced concrete (RC) columns and steel columns were used herein to form hybrid structural systems combining their distinct advantages. Eleven 3D building models subjected to earthquake excitation with reinforced concrete beams and slabs of 12 floors in height and with different distributions of mixed columns were analyzed by the SAP2000 software in order to investigate the most suitable distributions of a combination of reinforced concrete and steel columns. Top displacements and accelerations, base normal forces, base shear forces, and base bending moments were computed to evaluate the selected hybrid structural systems. The findings are helpful in evaluating the efficiency of the examined hybrid high-rise buildings in resisting earthquakes.

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Analysis of the Distribution Influence of the Density of Cost-forming Factors on Results of the LCCA Calculations

. Di Giuseppe, A. Massi, M. D’Orazio, “Probabilistic Life Cycle Cost analysis of building energy efficiency measures: selection and characterization of the stochastic inputs through a case study”. International High-Performance Built Environment Conference - A Sustainable Built Environment Conference 2016 Series (SBE16), iHBE 2016, Procedia Engineering. 2017 180:491-501 5. E. Fregonara, D. G. Ferrando, “How to Model Uncertain Service Life and Durability of Components in Life Cycle Cost Analysis Applications? The Stochastic Approach to the Factor Method

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Risk Analysis in the Realization of Buildings in Revitalized Areas

, “Economic efficiency of brownfield regeneration: Study of South Moravian projects,” Sci. Rev. Eng. Environ. Sci. , vol. 26, no. 2, pp. 151–158, 2017. [5] L. A. Haidar and A. Talib, “Adaptive Reuse in the Traditional Neighbourhood of the Old City Sana’a-Yemen,” Procedia - Soc. Behav. Sci. , vol. 105, pp. 811–822, Dec. 2013. [6] A. Dziadosz, “Przegląd wybranych metod wspomagających analizę ryzyka przedsięwzięć budowlanych,” Przegląd Bud. , vol. R. 81, nr 7-8, pp. 76–80, 2010. [7] D. Skorupka, “Zarządzanie ryzykiem w przedsi ęwzięciach budowlanych,” vol

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Causes of Rework in Construction Projects in Ukraine

. 11. J.L. Burati, J.J. Farrington, W.B. Ledbetter, “Causes of quality deviations in design and construction”, J. Constr. Eng. Manag., 118 (1): 34-49, 1992. 12. I. Rybka, E. Bondar-Nowakowska, K. Pawluk, M. Połoński, “Risk of contractors’ claims on the example of road works”, IOP Conference Series: Materials Science and Engineering, 245: 1-9, 2017. 13. R. Trach, M. Polonski, P. Hrytsiuk. “Modelling of Efficiency Evaluation of Traditional Project Delivery Methods and Integrated Project Delivery (IPD)”, IOP Conf. Series: Materials Science and Engineering

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Determination of the Lifetime Influence Upon the Conversion Efficiency of the Photovoltaic Silicon Solar Cells

. Schroder, Semiconductor material and device characterization, Third Edition, John Willey & Sons, Inc., 2006. [5] D.M. Chapin, C.S. Fuller, G.L. Pearson, A New Silicon p-n Junction Photocell for Converting Solar Radiation into Electrical Power, J. Appl. Phys. 25, 676, 1954. [6] N. Bateman, P. Sullivan, C. Reichel, J. Benick, M. Hermle, High quality ion implanted boron emitters in an interdigitated back contact solar cell with 20% efficiency, Proceedings of the 1st International Conference on Crystalline Silicon Photovoltaics, Energy Procedia, vol. 8, pp.509

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Analysis of Energy Efficiency and Financial Profitability for an Active Filter Equipment Used for Large Industrial Consumer

Abstract

The aim purpose of this paper is to analyze the efficiency of active filtering equipment use for a large industrial consumer connected to the national power system. Based on data acquisition system the technological process of the consumer is identified and modeled, and then is optimized from energy consumption point of view. The compensation of power factor by reducing the consumption of reactive power and the filtering methods for current harmonics are due by using active filters. The measurements of the power quality parameters with active filter installed, being compared with the ones without filter, confirm the results of research and clearly demonstrate the effectiveness of the implemented solution. To prove the effectiveness of the investment is developed a financial and economic calculation, making a benefit and cost ratio, calculation which clearly proves the profitability of this investment.

Open access
An Investigation of the Mechanical Properties of Sintered Fly Ash Lightweight Aggregate Concrete (SFLWAC) with Steel Fibers

Abstract

this study investigates the fresh and mechanical performance of concrete incorporating sintered fly ash lightweight aggregates (SFLWA) both with and without steel fibers. Comparative assessments of natural aggregates with sintered fly ash aggregates were evaluated. Mix design was obtained by the IS method for M30 grade concrete, and within the natural aggregates were replaced with 20%, 40%, and 60% amounts of SFLWA. The addition of SFLWA shows an increase in the workability of the concrete. Replacement with SFLWA increases with an increase in slump value, and decreases in strength parameters. Compressive strength of 42.6 MPa was achieved with a 40% replacement of SFLWA with steel fibers. The mechanical properties such as compressive strength, split tensile strength, flexural strength, elastic modulus, and structural efficiency of SFLWAC were examined, both with and without fibers. The incorporation of fibers drastically improved the mechanical properties of the mix.

Open access
The Profitability Analysis Of Enhancement Of Parameters Of The Thermal Insulation Of Building Partitions

Abstract

The energy saving tendencies, in reference to residential buildings, can be recently seen in Europe and in the world. Therefore, there are a lot of studies being conducted aiming to find technical solutions in order to improve the energy efficiency of existing, modernized, and also new buildings. However, there are obligatory solutions and requirements, which must be implemented during designing stage of the building envelope and its heating/cooling system. They are gathered in the national regulations.

The paper describes the process of raising the energy standard of buildings between 1974–2021 in Poland. Therefore, the objective of this study is to show energy savings, which can be generated by modernization of thermal insulation of partitions of existing buildings and by the use of different ways of heat supply. The calculations are made on the selected multi-family buildings located in Poland, with the assumption of a 15 years payback time.

It is shown that it is not possible to cover the costs of the modernization works by the projected savings with the compliance to the assumption of 15 years payback time.

Open access