The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this work we investigate the optical and thermal properties of In12Ga88N/GaN photovoltaic devices. These devices show very good solar cell characteristics with peak external quantum efficiency of 63%, open circuit voltage of 1.7 V, and a fill factor of 76%. Thermal measurements show no reduction in output power with increasing temperature up to 87??C.
Deploying a concentrator for a photovoltaic (PV) system has been proved to be one of the most efficient ways to reduce the junction material cost per watt output, and to increase the power output per unit module area facing the sun. In this paper a novel side-mounted concentrator solar module structure and design that could be rather compact and thin compared to current designs, and yet provides good...
The potential benefits of using nanomaterials in PV manufacture triggered a recent surge of research and development in this area. Nevertheless, the environmental- and health-implications of using them are not delineated fully. In this study, we present and discuss the potential life-cycle energy uses and hazards of three photovoltaic (PV) designs based on nanotechnology, i.e., multi-junction amorphous...
Results and progress are reported for a course of work to establish an efficient reliability test for the die-attach of CPV cell assemblies. Test vehicle design consists of a ~1 cm2 multijunction cell attached to a substrate via several processes. A thermal cycling sequence is developed in a test-to-failure protocol. Methods of detecting a failed or failing joint are prerequisite for this work; therefore...
The effect of spectral variations on the maximal achievable efficiency of multi-junction solar cells is investigated in this paper. The energy yield rather than power rating are considered here. With the optimized band gaps under STC the average and annual efficiency for spectral irradiances measured at CREST in a wavelength range from 310-1710 nm is calculated. The material band gap optimised for...
The traditional modular building block for space solar arrays consists of solar cells mounted to an aluminum honeycomb panel with carbon composite facesheets. This design not only provides the structural rigidity for the array, but is critical for heat dissipation during operation in the space. The honeycomb provides consistent thermal conduction and emissive properties throughout the panel, and good...
A convenient test-bench for quickly assessing the degradation and stability of an organic electronic device is proposed. The extent of degradation is quantified by the decrease in the current flowing through the device at a particular bias. The three parameters considered to affect the degradation are time, charge fluence through the device and energy dissipation in the device. Data from experimental...
Aim of this work, is the study of the properties of Aluminium Gallium Indium Phosphide for the realization of the next generation high-efficiency multi-junction (MJ) solar cells. (AlxGa1-x)0.50In0.50P (AlInGaP) is a semiconductor with a high direct bandgap that can be tuned between 1.81 eV and 2.00 eV varying the Al content in the range 0<x??0.12. This makes AlInGaP one of the most promising candidates...
Over the last several years, we have continuously increased the conversion efficiency of solar cells and modules. In this paper, we discuss new developments which led to a ~5% increase in conversion efficiency of cells and modules made using roll-to-roll deposition. The enhanced efficiency is attributed primarily to the replacement of the conventional Al/ZnO back reflector with a new Ag/ZnO structure...
We report to reduce the recombination rate and photocatalytic activity in dye-sensitized solar cells (DSSCs) by doping titania with a transition metal, niobium (Nb). Nb doped titania (anatase) was synthesized by hydrothermal method. The synthesized powders were characterized by thermogravimetric analysis (TGA), X-ray diffraction (XRD), and finally they were used as photoanodes in DSSCs. TGA analysis...
Explosive growth in photovoltaic markets has fueled new creative approaches that promise to cut costs and improve reliability of system components. However, market demands require rapid development of these new and innovative technologies in order to compete with more established products and capture market share. Oftentimes diagnostics that assist in R&D do not exist or have not been applied...
Back-contact silicon solar cells enable new concepts for the module design and assembly. Monolithic module assembly refers to a process whereby the solar cell circuit and the module encapsulation are accomplished during the lamination step. This paper describes the advantages of MMA, progress in design and qualification of a commercial module based on MMA, and first results on pilot-scale production...
The implementation of energy scavenging technologies in distributed, self-sufficient micro systems offers new approaches to the realization of long-time power supplies within reasonable system dimensions. In this article various technical solutions to supply a low-power micro system with basic functions and fixed energy requirements are examined from an environmental point of view. Based on the material...
One of the driving factors for a steady reduction in wafer and cell thickness is the present shortage of polysilicon feedstock combined with the need to reduce manufacturing costs in photovoltaic module production. Therefore materials and manufacturing processes must adapt to maintain acceptable mechanical yields and module reliability. The soldering of solar cell strings is a critical step in the...
It was shown in the recent experiments that the hybrid organic/inorganic resonant structures could provide a flexible materials platform aimed at the design of novel light emitting devices. The applications of hybrid structures for photovoltaic solar cell can also be useful. We pay attention in this note that the resonant energy transfer in hybrid structure from the organic thin layer to the semiconductor...
In order to get a deeper understanding of the conduction mechanisms limiting the electrical characteristics of ITO/PEDOT:PSS/P3HT:PCBM/Al solar cells, dark current-voltage measurements at different temperatures were analyzed using a compact electrical equivalent circuit previously used in p/n junctions. Between 0.2 V and 0.6 V, the current-voltage characteristic is modeled by an exponential term which...
We analyze the absorption enhancement in single and tandem solar-cells comprising nanostructures that increase the path of the photons inside the solar cell. For this purpose we exploit different physical phenomena in different material systems.
Organic photovoltaics are being explored for powering electronic devices by harvesting the sun's energy or indoor lighting. Such solar cells have shown promise as they can be deposited on thin flexible foils that enable flexibility of integration within products while keeping the weight light. Several R&D efforts are underway in creating improved organic solar cells in terms of their efficiency...
PV power generation is the most promising generation system, which is expected to overcome both global warming problems and energy resource shortage problems. However, the present PV systems are inferior to conventional generation systems in terms of power generation cost, resource securing and power quality, though its installation is increasing rapidly because of subsidy systems introduced by many...
Photoresponse of nitrogen and phosphorous doped n-C/p-Si heterostructure have been studied. Camphor (C10H16O) was used as starting precursor material in both cases. Phosphorous was doped in varying amounts (1%-7% by mass) and Nitrogen was doped in gas phase with varying partial pressure in the range from 0.3 to 50 mTorr. The doped carbon films were deposited on Silicon substrates by pulsed laser deposition...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.