Search results for " Solar"
showing 10 items of 958 documents
La1-xSrxCo1-yFeyO3-delta perovskites: Preparation, characterization and solar photocatalytic activity
2015
Abstract LaCoO3 perovskites substituted by Sr at the A site and/or by Fe at the B site have been prepared by the citrate method. Characterizations by several techniques, such as specific surface area (BET method), XRD, TPR, SEM, UV–vis in DRS mode, XPS and TGA analyses, have been performed. The so prepared La1−xSrxCo1−yFeyO3−δ perovskites are semiconductor materials showing band gap energy values from 1.9 to 3.2 eV. They displayed solar photocatalytic activity for the 2-propanol degradation in gas–solid regime. The photocatalytic results suggest that the perovskites containing Fe are less active and the activity decreases by increasing the Fe content, however the presence of iron avoids the…
Fabrication and electro-optical characterization of Ruthenium-based Dye-Sensitized Solar Cells
2015
In this paper, we measure the main photoelectrical parameters of Dye Sensitized Solar Cells (DSSCs) based on ruthenium complexes at different irradiance levels, incident wavelengths, temperatures and hours of light soaking
Experimental characterization of Ruthenium-based Dye Sensitized Solar Cells and study of light-soaking effect impact on performance
2016
In this paper, we present an experimental investigation on the performance of Ruthenium-based Dye Sensitized Solar Cells (DSSCs) at different irradiance levels, incident wavelengths and hours of illumination. In particular, the measurements have been aimed at studying the performance variation due to light soaking effect since this phenomenon has noteworthy practical implications, such as stability tests of DSSCs. Our results show that the short circuit current density, the open circuit voltage and the conversion efficiency η increase with the hours of light soaking. Finally, the observed phenomenon is reversible, and thus the performance decreases again when the cell is kept in the dark.
Characterization of Thin Film CIG(S,Se)2 submodules using Laser Beam Induced Current Technique
2015
Nowadays, an important class of thin film solar cells consists of CuInGa(S,Se)2 (CIGSSe) solar cells, i.e., composed of Copper, Indium, Gallium, Sulfur and Selenide. Thanks to their electrical and optical properties and to the technological development, thin film integrated photovoltaic modules have nowadays obtained relatively good values of efficiency. In this work, we have performed the electrical and optical characterization of a CIGSSe sub-module by using both a solar simulator equipment and the Laser Beam Induced Current (LBIC) technique.
ELISA: A simplified tool for evaluating the Environmental Life-cycle Impacts of Solar Air-conditioning systems
2018
The paper presents ELISA, a simplified tool for estimating the Environmental Life-cycle Impacts of Solar Air-conditioning systems. The tool is designed to support researchers, designers and decision makers in a simplified evaluation of the life cycle energy and environmental potential benefits related to the installation of solar heating and cooling systems in substitution of conventional ones. The tool was developed within the research activities of Task 53 “New Generation Solar Cooling & Heating Systems (PV or solar thermally driven systems)” of the International Energy Agency.
Energy evaluation and life cycle assessment of an innovative building integrated technology: the smart window-luminescent solar concentrator
2022
Luminescent Solar Concentrators (LSC) represent one of the innovative and potentially most versatile technologies related to Building Integrated Photovoltaics (BIPV). The peculiarity of these devices lies in the fact that they can be integrated into the surface of the building to replace openings such as skylights or windows, thanks to their characteristic of being semi-transparent and of functioning both with direct and diffused radiation. Eni developed the own technology Eni Ray Plus® based on LSC and integrated it in a multifunctional smart window-LSC (SW-LSC) prototype. The device uses the energy produced by LSC modules to power an autonomous and passive shading system, exploiting irrad…
Colloidal Self-assembled Nanosphere Arrays for Plasmon-enhanced Light Trapping in Thin Film Silicon Solar Cells
2014
To realize high-efficiency thin-film silicon solar cells it is crucial to develop light-trapping methods that can increase absorption of the near- bandgap light in the silicon material. That can be achieved using the far-field scattering properties of metal nanoparticles (MNP) sustaining surface plasmons. The MNPs should be inserted in the back of the cell, embedded in the transparent conductive oxide (TCO) layer which separates the rear mirror from the silicon layers. In this way, a plasmonic back reflector (PBR) is constructed that can redirect light at angles away from the incidence direction and thereby increase its path length in the cell material. In this work, a novel technique is pr…
Effect of the linkage location in double branched organic dyes on the photovoltaic performance of DSSCs
2015
Two novel double branched D–π–A organic dyes (DB dyes) are synthesized to investigate the influence of the linkage location in DB dyes on the performance of dye-sensitized solar cells (DSSCs), where phenothiazine is introduced as a donor, thiophene–benzotriazole unit as the π-bridge and cyanoacrylic acid as the electron-acceptor. The photophysical, electrochemical and photovoltaic properties of the dyes are systematically investigated. The results show that the location of the linkage unit has a small effect on the physical and electrochemical properties of the dyes. However, when the dyes are applied in DSSCs, an obvious decline of short-circuit current (Jsc) and open-circuit voltage (Voc)…
Luminescent Solar Concentrator (LSC): preliminary phases of the LCA analysis applied to the Smart Window-LSC
2019
Luminescent solar concentrators (LSC) represent one of the innovative technologies related to Building Integrated PhotoVoltaics (BIPV). T hanks to their characteristic of being semi-transparent and of functioning both with direct and diffused radiation, the se devices can be integrated to the surface of the buildings, in particular in replacement of openings such as skylights or windows. They do not require solar tracking systems that are used in classic solar concentrators and allow reducing the presence of silicon compared to traditional photovoltaic panels.
The force-free twisted magnetosphere of a neutron star
2016
We present a detailed analysis of the properties of twisted, force-free magnetospheres of non-rotating neutron stars, which are of interest in the modelling of magnetar properties and evolution. In our models the magnetic field smoothly matches to a current-free (vacuum) solution at some large external radius, and they are specifically built to avoid pathological surface currents at any of the interfaces. By exploring a large range of parameters, we find a few remarkable general trends. We find that the total dipolar moment can be increased by up to $40\%$ with respect to a vacuum model with the same surface magnetic field, due to the contribution of magnetospheric currents to the global ma…