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.
The simulation of the quantum efficiency and the I-V curves at several concentrations of a high efficiency concentrator dual-junction solar cell is presented using three different approaches: 1) analytic simulation with the one-diode model; 2) analytic simulation with distributed circuit models; and, 3) numerical simulation. The main advantages and limitations of each model are discussed and their...
In search of solar cell concepts that allow processing thinner wafers (<150 micron), the conventional full Al rear side is replaced by an open rear metallization combined with a dielectric passivation layer. We show a gain of 2.1% (relative) in the product of Jsc??Voc, when we apply a passivated SiNx dielectric layer and local Al contacts on the rear of p-type mc-Si solar cells instead of a full...
The addition of quantum dots (QDs) or quantum wells (QW) to a solar cell allows one to extend the absorption spectrum of the solar cell to match spectral conditions under concentration. In this paper the effect of bandgap tuning using quantum dots is investigated. P-i-n GaAs concentrator solar cells, both with and without InAs QD superlattice (SL) inserted into the i-region, were fabricated. In order...
It is now well known that solar trackers pay for themselves with PV systems in field installations relative to fixed mounted systems by generating up to 1.4 times more kWh per kW installed. Solar trackers such as the JX Crystals' carousel tracker can also be profitably installed on commercial building flat rooftops. A commercially available JXC carousel tracker is equipped with six 200 W Sanyo planar...
In this paper, the benefits of the ultra high concentration (?? 1000 suns) are shown in terms of cost reduction and efficiency increase. Accordingly, the strategy followed at IES-UPM for more than 15 years is the development of III-V solar cells suitable for operation at 1000 suns or more. Recently, we have developed and manufactured a GaInP/GaAs dual-junction cell which results in an efficiency (measured...
A simple model based on the simulation of distributed series resistance effects in solar cells is presented. This model overcomes limitations of the standard two-diode model representation of solar cells in respect to fitting Suns-Voc (m-Voc) and Jsc-Suns curves. The model results include (i) an improved understanding of two-dimensional current flows in shunted solar cells, (ii) the prediction of...
Theoretical and experimental studies were performed to explore the effect of light intensity on the performance of silicon-based thin film solar cells. The theoretical study was conducted using AMPS-1D (Analysis of Microelectronic and Photonic Structures) to analyze how the device structure affects the performance of silicon-based solar cells under various concentration ratios of sunlight. We calculated...
The objective of this work is to present the design, construction and energetic performance evaluation of a polyhedral (four-face) low concentration mirror system. The concentrator generatrix is a straight line, so it is of the so-called single-sectional type. In the geometry design it has been considered only on reflection of the light in the mirrors before reaching the PV module and uniform illumination,...
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...
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...
This paper will describe a technology and process for providing reduced thermal resistance between CPV receivers and heat sinks, resulting in improved thermal performance and increased life span for the system.
For a solar array powering a mission designed to operate near the sun, a trade study was performed to calculate the effect of changing the operating temperature of the solar array on the required area of the thermal radiator required to moderate the array temperature.
Very High Efficiency Solar Cell (VHESC) program is developing integrated optical/photovoltaic modules for portable applications that operate at 50 percent efficiency. Test sub-modules incorporating four p-n junctions and corresponding optics have been realized and are predicted to realize efficiency greater than 40%. Phased implementation requires corresponding measurement to inspect accomplished...
InGaP/GaAs dual junction (DJ) solar cells were fabricated on epitaxial liftoff (ELO) 100 mm diameter GaAs wafers. These ELO DJ cell wafers have total semiconductor thickness less than 5 ??m and weigh less than 1.7 g. The best solar cells exhibited an efficiency of 28.69% at one sun AM1.5D illumination, which is the highest reported efficiency for DJ ELO thin cells to date. The DJ ELO cells had fill...
It is essential to obtain high values of tolerance for PV concentrators because manufacturing process always implies some accuracy errors. In this way, three new free-form concentrators are presented here, combining high geometric concentration and high tolerance (high acceptance angle). This is achieved by using the SMS3D design method, which is the most advanced method to design free-form surfaces...
The market for large PV systems is growing rapidly. An innovative 120x point focus concentrating system has been designed with the objective of achieving the lowest possible installed system price. As far as possible, extrapolations from one sun technology have been used. The Laser Grooved Buried Contact (LBGC) solar cell was chosen for the lowest cell ??/Wp cost. One sun lamination technology was...
In this paper we report on research activities at the Fraunhofer Institute for Solar Energy Systems (ISE) and Concentrix Solar in the area of secondary optics for FLATCON?? modules. This concentrator photovoltaic (CPV) technology is based on Fresnel-lenses as primary optics, passive heat spreaders and triple-junction III-V solar cells. In the first part of the paper, a field performance analysis is...
This paper presents design, development and testing of a modular solar engine for CPV. Solar cell, heat pipe, package substrate, heat sink, secondary optics rod and wirings are integrated in a self-contained, plug-and-play module. The integrated solar engine can generate 30 W per 1 cm2 solar cell area with natural (passive) cooling.
Traditional illumination lights are energy- consumption and not economical in the long term. While the solar lights are safe, easy to maintenance, independent of conventional energy, no pollution to environment. With the cost of the solar cells decreasing, the solar lights have been applied widely. Meanwhile photovoltaics are one of the fastest growing solar energy technologies. Photovoltaic devices,...
In this paper we characterize the first functional, lattice matched, GaInP/GaInAs/Ge triple junction solar cells grown and manufactured in our lab with an efficiency conversion of 31.5% at a concentration level of 1000 suns. This is our first approach for transferring the world record double junction solar cell, also developed in our group, into a Ge substrate. First experimental results are presented...
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.