Due to the observed increase of photovoltaic installations capacity in Poland, the research on the performance of different modules became an important issue from the practical and scientific point of view. This paper is intended to help system planners to choose photovoltaic modules and inverters taking into account the actual operating conditions. The study is devoted to the assessment of four different technologies of photovoltaic modules: polycrystalline silicon (pc-Si), amorphous silicon (a-Si), copper indium gallium selenide (CIGS), and cadmium telluride (CdTe). The data was collected at a solar plant located at high latitude location, in the eastern part of Poland, during the fourth year of the plant operation. The influence of irradiance on the temperature and efficiency of modules was studied. The results show that the efficiency of the pc-Si and CIGS modules decreases with rising temperature; however, the efficiency of the a-Si and CdTe modules is more stable. The impact of changing external conditions on the inverter efficiency as well as array and system losses during various seasons of the year was shown. The inverter efficiency reaches up to 98% in summer and drops as low as 30% in winter. Small average array capture losses of 7.41 (kWh/kWp)/month (0.25 h/day) are observed for the CIGS and 10.4 (kWh/kWp)/month (0.35 h/day) for pc-Si modules. The a-Si and CdTe array losses are higher, up to 2.83 h/day for CdTe in summer. The results indicate high annual energy yields of the pc-Si and CIGS modules, 1130 kWh/kWp and 1140 kWh/kWp, respectively. This research provided new data on pc-Si and especially the performance of the thin film modules and losses in a photovoltaic installation under temperate climate.

This study presents a comparative analysis of energy production over the year 2015 by the grid connected experimental photovoltaic (PV) system composed by different technology modules, which operates under temperate climate meteorological conditions of Eastern Poland. Two thin film technologies have been taken into account: cadmium telluride (CdTe) and copper indium gallium diselenide (CIGS). Rated power of each system is approximately equal to 3.5 kWp. In addition, the performance of a polycrystalline silicon technology system has been analyzed in order to provide comprehensive comparison of the efficiency of thin film and crystalline technologies in the same environmental conditions. The total size of the pc-Si system is equal to 17 kWp. Adequate sensors have been installed at the location of the PV system to measure solar irradiance and temperature of the modules. In real external conditions all kinds of modules exhibit lower efficiency than the values provided by manufacturers. The study reveals that CIGS technology is characterized by the highest energy production and performance ratio. The observed temperature related losses are of the lowest degree in case of CIGS modules.

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The cxpcrirriental rcsults of a study of the effect of supcrsaturation and temperature on the growth morphology of ammoniuni oxalatc monohydrate [ (NH&C201 . H 2 0 ; AO] single crystals obtained from aqueous soliltions at 30 and 40 "C and supcrsaturation up to 9% arc presented. The observations arc analyscd in terms of theoretical morphology, growth models and attachment cncrgy for growth imits in steps of growing faces.

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The fast development of new organic sensitizers for the purposes of dye-sensitized solar cells and photocatalysis requires a better understanding of the complexity of their electronic states on TiO2 surface. This paper describes a study of carboxylated derivatives of all-trans carotenoids retinoic acid (ATRA) and bixin by Stark effect (electroabsorption) spectroscopy in glassy ethanol at low temperature, both as free monomeric species and when adsorbed to nanoparticles of titanium dioxide in the presence of a variable concentration of acetic acid. Both pigments adsorbed strongly at the lowest acid contents (<0.2%), but become partially desorbed at the higher acid concentration (2%). Adsorption of pigments on TiO2 was accompanied by an increase of difference dipole moment Δμ between the ground and excited states from 14.5 to 22.5 D for ATRA. A smaller change in Δμ was estimated for bixin. The remarkable spectral inhomogeneity exhibited by significant fractions of both pigments with larger values of Δμ is ascribed to the differences in bonding to TiO2. The gradual spectral shift due to the charging of nanoparticles induced by the increasing acetic acid concentration was used to estimate the change in surface electric field of charged nanoparticles.

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Hybrid photovoltaic installations, defined as on-grid PV system in cooperation with battery energy storage system (BESS), are still rare among the typical investors because the investment cost of the hybrid installation is significantly higher than the one of the on-grid system. However, while considering the broader perspective, such as environmental or technological aspects, the mentioned solution can be competitive with photovoltaic on-grid systems and therefore should be carefully tested in the widest possible context. In this study, the authors compared 3.05 kW of peak power hybrid and on-grid installations operating in temperate climate conditions (Eastern Poland) using economic indicators, such as dynamic generation cost (DGC) and benefit–cost rate (BCR); environmental impact indicators (IMPACT 2002+ and GWP 100a) determined using Life Cycle Assessment (LCA); and technological aspects consideration, including the reliability of examined systems. Creating a ranking of the considered solutions based on the equal weighting factors assigned to the appropriate features allows indicating the technological areas where the competitiveness of hybrid systems justifies the increased investment costs. One such area is business, where the economic criterion, the only negatively assessed one in the standard operation, can be radically changed by the possible financial losses due to interruption of energy supply.