Search results for " Solar"

Simultaneous determination of carrier lifetime and electron density-of-states in P3HT:PCBM organic solar cells under illumination by impedance spectr…

2010

We report new insights into recombination kinetics in poly(3-hexylthiophene):methanofullerene (P3HT:PCBM) bulk heterojunction (BHJ) solar cells, based on simultaneous determination of the density of states (DOS), internal recombination resistance, and carrier lifetime, at different steady states, by impedance spectroscopy. A set of measurements at open circuit under illumination was performed aiming to better understand the limitations to the photovoltage, which in this class of solar cells remains far below the theoretical limit which is the difference between the LUMO level of PCBM and the HOMO of P3HT (∼1.1 eV). Recombination kinetics follows a bimolecular law, being the recombination ti…

Uncertainties in polarimetric 3D reconstructions of coronal mass ejections

2015

P.P. acknowledges STFC for financial support. Date of Acceptance: 21/01/2015 Aims. The aim of this work is to quantify the uncertainties in the three-dimensional (3D) reconstruction of the location of coronal mass ejections (CMEs) obtained with the so-called polarization ratio technique. The method takes advantage of the different distributions along the line of sight of total (tB) and polarized (pB) brightnesses emitted by Thomson scattering to estimate the average location of the emitting plasma. This is particularly important to correctly identify of CME propagation angles and unprojected velocities, thus allowing better capabilities for space weather forecastings. Methods. To this end, …

Energies Renovables i el seu Condicionament

2017

El document forma part dels materials docents programats mitjançant l'ajut del Servei de Política Lingüística de la Universitat de València La matèria “Energies Renovables i elassignatura amb el mateix nom i forma part del bloc comú de matèries pròpies de la branca de Telecomunicacions. S'imparteix en el primer quadrimestre del tercer curs de les titulacions de Grau en Enginyeria Electrònica de Telecomunicació i Grau en Enginyeria Telemàtica i com assignatura optativa al quart curs del Grau en Engineria Electrònica Industrial. La càrrega lectiva total és de 6 ECTS. La càrrega de treball per a l’estudiant és de 150 hores al llarg del quadrimestre, de les quals 60 són presencials i 90 són de …

Il sole dappertutto nelle nostre città. L’idea di Giovanni Francia

2010

Sviluppo di un convertitore di energia solare (S.E.C. - Solar Energy Converter) per applicazioni di efficientamento energetico in agricoltura attrave…

2014

Review of sustainable solar hydrogen production using photon fuel on artificial leaf

2017

Abstract Energy conversion from the renewable energy sources with suitable energy storage plays a vital role in the sustainable development. Sustainable hydrogen production from the solar energy is well suited for energy storage applications because of inherent high mass energy density of hydrogen. This manuscript reviewing the techniques required for the sustainable solar hydrogen production using photon fuel on artificial leaf, i.e. solar cell. The designing and assembling of artificial solar leaf, which is the replica of natural leaf and capable of harnessing full solar spectrum, are deliberated. This technology for sustainable solar hydrogen production will overlay a viable way for more…

Synthesis and characterization of zinc carboxy–porphyrin complexes for dye sensitized solar cells

2018

Two zinc porphyrins, 2 and 8, have been synthesized. Porphyrin 8 displays better electronic communication between the dye and the TiO2 electrode. Photophysical measurements and electrochemistry experiments suggest that both porphyrins are very promising sensitizers for dye-sensitized solar cells (DSSCs). It was found that their molecular orbital energy levels favor electron injection and dye regeneration in DSSCs. Solar cells sensitized by 2 and 8 were fabricated, and it was found that they show power conversion efficiencies (PCEs) of 5.27% and 7.13%, respectively. Photovoltaic measurements (J–V curves) together with the incident photon-to-electron conversion efficiency spectra of the two c…

Reconfiguration strategies to reduce mismatch effects on PV array: An Arduino-based prototype

2014

Today, solar energy represents a widespread source of electricity among all the renewable energies. One of the major problems concerning the photovoltaic (PV) arrays is the partial shading, that is the non-uniform irradiance on its parts. The partial shading leads to several undesired effects, such as mismatch between modules and a reduction of the production of electric energy. In order to alleviate the partial shading effects, different methods can be employed. Among them, the reconfiguration of the electrical connections between modules represents an alternative solution. In this paper, an algorithm of reconfiguration for a small-scale PV plant is proposed and experimental results showin…

Maintance by water-cleaning and efficiency reduction of pv panels

2019

With the increase in the use of solar energy, both in civil and industrial environments, the problem of maintenance of photovoltaic panels becomes extremely important. In this work attention is restricted to the problem of cleaning and safety conditions of the photo-voltaic (PV) panels and a brief review of main effects determining their efficiency reduction are reported. The discussion related to problems and unsafe functioning conditions concludes this paper.

Analyses of innovative glass blocks for BIPV: assessment of thermal and optical performance

2015

This paper illustrates the results of the performance analyses conducted on an innovative glass block integrated with thirdgeneration dye-sensitised solar cells (DSCs), designed to enable the construction of translucent and sustainable building envelopes. The analyses include the simulation of both thermal and optical performance with regard to different configurations of the photovoltaic (PV)-integrated glass block, and the results obtained are presented using two different programs: Comsol Multiphysics and WINDOW. The configurations may differ – for example, because of the position of the module inside the glass block, the type of DSC module used (composition, transparency, design) and th…