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Photovoltaic Systems (photovoltaic + system)
Selected AbstractsEconomic analysis of small photovoltaic facilities and their regional differencesINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 3 2004M. Varela Abstract Small grid-connected photovoltaic (PV) facilities in Spain receive either a premium of 0.36, kWh,1 over the average price on the power market or a fixed price of 0.40, kWh,1. However, legislation on this matter (Royal Decree 2818/98) requires a periodic review of these figures. The basis of on-going revision of these prices has been their profitability. However, the economic success of such PV facilities is clearly affected by the amount of solar radiation at the site where they are located. Since Spain is between latitudes 44 and 36° in the northern hemisphere, the feasibility of these systems must be analysed for different regions. Two different models have been used to produce the required input data for such an analysis: a model that generates typical solar radiation years and temperatures taken from satellite images and an empirical model for the prediction of daily power produced by a grid-connected photovoltaic system. From the results of this regional economic analysis, it may be concluded that the existing prices are insufficient in and of themselves to make these small grid-connected systems profitable anywhere in Spain. To guarantee the economic feasibility of these PV installations in any given location, the fixed price paid for the electricity should be around 0.93, kWh,1. Nevertheless, if the Government were to double the current fixed price, in consideration of the slow increase in the PV market in recent years, this would mean that small grid-connected installations would become profitable in at least 77% of the Spanish territory. Copyright © 2004 John Wiley & Sons, Ltd. [source] Photonics in photovoltaic systemsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 12 2008Andreas Gombert Abstract This paper gives an overview on photonics for photovoltaic systems. Starting from the spectral and angular distribution of the electromagnetic radiation from the sun, many important optical approaches how to improve the efficiency of solar cells are presented and discussed. Topics include antireflective coatings, various light trapping structures, refractive, reflective and fluorescent concentrators, and components for spectral management. The theoretical background is shortly described and examples of the experimental and also of the commercial realisation are given. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Comparison of potential solar electricity output from fixed-inclined and two-axis tracking photovoltaic modules in EuropePROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 1 2008Thomas Huld Abstract We present an approach to determine the potential energy gains of flat plate non-concentrating photovoltaic systems for the case of two-axis tracking and two inclination angles with fixed orientation (assuming biannual adjustment) compared to the configuration of single fixed optimum angle. The calculation is based on the Photovoltaic Geographic Information System (PVGIS), which integrates modelling tools with the pan-European solar radiation database. The results indicate that in the case of a PV system with two seasonal inclination angles, the maximum yearly gains, compared to the single fixed optimum angle, do not exceed 60,70,kWh per kWp in the Mediterranean region, while in the Baltic and North Sea regions this configuration gives less than 20,kWh extra. For the case of two-axis tracking, the relative energy gain compared to single fixed optimum angle is highest in the Northern latitudes but the absolute gain is much higher in the South. Typical yearly gains in Portugal and the Mediterranean region are in the range of 400,600,kWh per kWp. The smallest absolute increase is found in the Northwest and Central Europe including the British Isles, where it is lower than 250,kWh per kWp. For crystalline silicon we also investigate the effects of temperature and shallow-angle reflectivity on the comparison between fixed and tracking systems. While both effects reduce the overall energy output, the temperature degradation is stronger for tracking systems while the reflectivity reduces output more for fixed systems. The combined effect is almost equal for fixed and two-axis tracking systems. Copyright © 2007 John Wiley & Sons, Ltd. [source] Characterization of optical collectors for concentration photovoltaic applicationsPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 6 2003I. Antón Abstract The design and characterization of the collector of a photovoltaic concentrator system is commonly carried out for a given receiver, the optical parameters of the collector being linked to it. This paper, which has substantial tutorial content, deals with the characterization of collectors for concentrator photovoltaic systems, independently of any receiver, and providing the necessary parameters for the design of a system. This strategy allows the parameters related to the collector and the receiver, which are usually manufactured by different industries, to be totally separated. It also allows the optical collectors coming from non-photovoltaic industries to be evaluated. The information that the mirror and lens manufacturers should provide for a photovoltaic concentrator application can be summarized under three characteristics: overall optical efficiency; light distribution; and acceptance angle. Theory, equipment, and procedures to carry out the optical characterization of the collectors are explained. Copyright © 2003 John Wiley & Sons, Ltd. [source] Manufacturing technology for terrestrial PV systems: high efficiency crystalline Si through amorphous SiPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 2 2002Minoru Kaneiwa In order to meet the rapidly growing demands for solar power photovoltaic systems, grounded on public consciousness of global environmental issues, Sharp has increased the production of solar cells and modules 50-fold in last 7 years. Efforts to establish manufacturing technologies of solar cells for terrestial use and approaches toward high light-to-electricity conversion efficiency using silicon material (crystalline to amorphous ) are described. Copyright © 2002 John Wiley & Sons, Ltd. [source] Grid-connected photovoltaic systems: the Brazilian experience and the performance of an installationPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 5 2001Sérgio Henrique Ferreira de Oliveira Just as in several other countries, the Brazilian experience of installing in place solar photovoltaic technology was first aimed at meeting the needs of rural areas. More recently, the effects of the international trend towards grid-connected photovoltaic systems are beginning to be felt in Brazil. In less than five years, the first four grid-connected photovoltaic systems have been installed, and other projects are in progress. This work presents the overall characteristics of the first four systems and the technical performance achieved by one of them, with an annual production in the range of 1500,kW,h/kWp. Copyright © 2001 John Wiley & Sons, Ltd. [source] Limiting photovoltaic monochromatic light conversion efficiencyPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 4 2001Martin A. Green Notwithstanding the relatively low energy conversion efficiencies typical of standard solar photovoltaic systems, photovoltaic cells are shown, in principle, to be capable of converting well-collimated monochromatic light at efficiencies arbitrarily close to 100%. To approach such efficiencies, radiative recombination must be the main recombination process within the cell. The intensity of the monochromatic light must be high, and the cell should be designed so that it does not absorb or emit light outside the range of angles and wavelengths required to accept the incident monochromatic light. The thermodynamic basis of such high efficiency is also briefly discussed. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||