V-trough Concentrator Research Articles

Modelling and simulation of Λ-ridge concentrator system using commercial PV modules

This paper presents the Λ-ridge and V-trough concentrator system with low concentration ratio applicable in independent power supply systems (e.g. chalets, road signs, traffic lights, street lamps, industrial cameras, CCTV), of an outpower not exceeding 500W. Actual area of photovoltaic modules, which doesn’t exceed 3m2 constitutes important parameter in this kind of construction. Small external dimensions and relatively light weight are the crucial principles of constructing Λ-ridge concentrator system. The performance of the system and the amount of energy produced constitute key factors for such restrictions. A series of simulations was conducted enabling evaluation of the efficiency of the presented systems depending on their technical parameters and weather conditions.

A comprehensive multi-physics model of photovoltaic modules with non-uniform solar concentration and serpentine cooling

This paper focuses on the multi-physics modeling of photovoltaic modules with solar concentration and cooling. The first step of the proposed modeling approach is optical modeling of the solar concentrators to determine the solar flux distribution on the photovoltaic module. Using the solar flux distribution by the concentrator, the thermal performance of the photovoltaic module was calculated for various cooling cases. The temperature and solar irradiance distributions were then used to model the electrical performance using a newly proposed cell-based electrical model for photovoltaic modules. The model was used to study the impact of solar concentrator design and cooling system design on the electrical performance of the photovoltaic system. Multiple cases with different working fluid velocities showed that the compound parabolic concentrator focuses the solar flux close to the edges of the photovoltaic module on focal points of the parabolic reflectors, where the concentration ratio rose to 18. It resulted in extreme non-uniformity of irradiance and cell temperature over the module, which resulted in only a 7 % increase in the electrical power output when the 2x compound parabolic concentrator was added to the photovoltaic module. Water cooling significantly improved over 35 % in power output and a 16 % reduction in average temperature even for the most straightforward heat exchanger design (4 bends) and with the lowest inlet velocity (0.1 m/s). The study results show that a simple V-trough concentrator design improves electrical performance compared to the more complicated compound parabolic concentrator.

A new configuration of V-trough concentrator for achieving improved concentration ratio of >3.0x

A new configuration of V-trough solar concentrator is proposed, constructed and investigated in an attempt to improve the concentration ratio of the V-trough concentrators. The new design consists of two conventional V-trough concentrators arranged in a cross, which lead to improvement in concentration ratio and angular response. The results of an experimental study show that the concentration ratio of this new configuration (referred to as OVSC) is 40%–60% higher than its corresponding conventional V-trough solar concentrator (CVSC) with additional benefits. The study reveals that the angular response of this new configuration is better than conventional V-tough concentrator with a potential to reduce the cost of concentrators by using less reflector materials. Surprisingly, the improvement in the concentration ratio is not accompanied by significant reduction in optical efficiency and light uniformity, making it a better alternative for low-cost and low concentration applications in future. • A new design of V-trough concentrator (VSC) enabling higher concentration ratio beyond the limits of conventional VSCs. • Concentration ratio of >3 obtained while keeping the VSC simplicity and similar optical efficiency and light uniformity. • Concentration ratio is improved with added benefit of better angular response and reduced fabrication cost.

A novel model for optimizing tilts of four reflectors on a flat plate thermal collector: Case study in Ouargla region

Enhancing the produced thermal energy of a flat plate thermal collector by increasing the received sunlight using reflectors is an economical solution. For this purpose, tilts optimization of four identical planar reflectors surrounding a fixed and a bi-axial tracked flat plate thermal collector in the southeast of Algeria was investigated experimentally and by simulating novel mathematical model. The findings showed that the novel tilt angles of the reflectors in the fully tracked case, which were fixed at 67° anywhere throughout the year. On the other hand, in the fixed case, they varied from one month to another. According to the simulation results, the average annual solar irradiation was increased by 64% in the stationary system without shadowing and by 111.28% in the two-axis solar tracked system. Experimental results showed that the daily average benefit ratio of incoming sunlight and the produced thermal energy for a two-axis tracked V-Trough concentrator were considerably enhanced, especially the received irradiation, and were equal to 4.25 and 2.48, respectively. However, in the fixed case, the improvements were only 1.52 and 1.33, respectively.

Thermal Profile of a Low-Concentrator Photovoltaic: A COMSOL Simulation

With the gradual reduction of fossil fuels, it is essential to find alternative renewable sources of energy. It is important to take advantage of substitutes that are less expensive and more efficient in energy production. Photovoltaic concentrators (CPVs) are effective methods through which solar energy can be maximized resulting in more conversion into electrical power. V-trough concentrators are the simplest types of low-CPV in terms of design as it is limited to the use of two plane mirrors with a flat photovoltaic (PV) plate. A consequence of concentrating more solar radiation on a PV panel is an increase in its temperature that may decrease its efficiency. In this work, the thermal profile of the PV plate in a V-trough system will be determined when this system is placed in different geographical locations in Saudi Arabia. The simulation is conducted using COMSOL Multiphysics software with a ray optics package integrated with a heat transfer routine. The 21st of June was chosen to conduct the simulation as it coincides with the summer solstice. The employment of wind as a cooling method for V-troughs was investigated in this work. It was found that with the increase in wind speed, the PV panel temperature dropped significantly below its optimum operating temperature. However, due to the mirrors’ attachment to the PV panel, the temperature distribution on the surface of the panel was nonuniform. The temperature gradient on the PV surface was reduced with the increase of wind speed but not significantly. Reducing the size of the mirrors resulted in a partial coverage of solar radiation on the PV surface which helped in reducing the temperature gradient but did not eliminate it. This work can assist in testing numerous cooling models to optimize the use of V-troughs and increase its efficiency especially in locations having high ambient temperatures.

Experimental and economical performance investigation of V-trough concentrator with different reflectance characteristic in photovoltaic applications

Lack of consideration of photovoltaic panel temperature in a concentrating photovoltaic (CPV) system causes a great misconception and leads to the financial risk of system installation since the increment in PV cell temperature significantly reduces the performance. In this study, an energy-efficient and cost-effective V-trough PV system with low-temperature configuration was proposed to achieve better performance by using easily accessible reflector material instead of the high reflective anodized aluminum reflector with high cost. The concentrating photovoltaic systems were designed, produced, and installed. Anodized aluminum reflector (AAR) protected with nanocomposite using a coil-coating, and polished stainless steel (PSSR) were used as reflector mirrors. The electrical performance parameters of CPVs were experimentally analyzed as a function of cell temperature and compared with a 1-Sun PV system. The net present value (NPV) method was used for the economical evaluation of the system. The results indicate that high reflectivity can cause the temperature elevation in the PV cell thereby decreasing the fill factor, voltage, and power output of the system. The power generation of the AAR-CPV system was about 17.4% lower than that of the 1-Sun PV system due to higher cell temperature. On the other hand, a low reflective PSSR-CPV system generates about 17.84% and 42.7% higher power compared to 1-Sun PV and AAR-CPV systems, respectively. The payback period of PSSR-CPV appears to be 6 years and is equal with that of the PV system on a yearly basis, however, PSSR-CPV yields a greater return. An easily accessible polished stainless steel having reasonable reflectivity may be a better attitude for increasing the incident solar irradiation with a slight increase in the PV cell temperature for a CPV system based upon the economical and experimental analysis for a cost-effective and energy-efficient design of CPV technology.

Performance assessment of a V-trough photovoltaic system and prediction of power output with different machine learning algorithms

This study carried out in two stages. In the first stage, four different-sized layers were designed and manufactured for a concentrated photovoltaic system. These layers were used to change the concentration ratio and area ratio of the system. Furthermore, a new power coefficient equation with this paper is proposed to the literature for the determination of the system performance. In the second stage of the study, the power outputs measured in the study were predicted with four machine-learning algorithms, namely support vector machine, artificial neural network, kernel and nearest-neighbor, and deep learning. To evaluate the success of these machine learning algorithms, coefficient of determination (R2), root mean squared error (RMSE), mean bias error (MBE), t-statistics (t-stat) and mean absolute bias error (MABE) have been discussed in the paper. The experimental results demonstrated that the double-layer application for the concentrator has ensured better results and enhanced the power by 16%. The average concentration ratio for the double-layer was calculated to be 1.8. Based on these data, the optimum area ratio was determined to be 9 for this V-trough concentrator. Furthermore, the power coefficient was calculated to be 1.35 for optimum area ratio value. R2 of all algorithms is bigger than 0.96. Support vector machine algorithm has generally presented better prediction results particularly with very satisfying R2, RMSE, MBE, and MABE of 0.9921, 0.7082 W, 0.3357 W, and 0.6238 W, respectively. Then it is closely followed by kernel-nearest neighbor, artificial neural network, and deep learning algorithms, respectively. In conclusion, this paper is reporting that the proposed new power coefficient approach is giving more reliable results than efficiency data and the power output data of concentrated photovoltaic systems can be highly predicted with the machine learning algorithms.

The Performance of V-Trough Solar Concentrator Photovoltaic Systems at Varying Panel Surface Temperatures

The photovoltaic (PV) panel performances are dependent upon many factors. A study was executed to ascertain the effect of a V-Trough Concentrator (VTC) to be engaged on a PV Panel in this research where the performance of PV panels are compared at different surface temperatures both back and front. The experiment was conducted using two similar rated monocrystalline PV panels. One of the PV panels was installed with a VTC while the other is without the VTC that served as Control for benchmark purposes. The optimum VTC selected is a 60° VTC. Both PV systems were built with a lower supporting mechanism and were placed to operate under similar operating and weather situations, while the PV panel surface temperature both front surface and back surface, Open Circuit Voltage (Voc), as well as Short-Circuit Current (Isc) readings are being recorded down at specific time. The theoretical output is determined and compared. This paper ends with a presentation of the results obtained in a study on the PV panel surfaces temperature in relation to its performance by PV system using a 60o VTC.

Performance of Solar Module with Presence of Two Types of Reflectors in Concentrator System

Any work to improve the performance of the solar modules could add to their economic competitiveness against fossil fuels. In the present work the performance of PV solar module was improved by using V-Trough concentrator system (CPV) which moved by two axis tracking system. The concentrator consists of two flat reflectors of area 2 m2 for each one with geometric concentration ratio of 2X. To optimize the performance of the V-Trough CPV systems, two types of reflector material, Aluminum and mirror (glass coated by silver nitrate) were used. The results indicated that the temperature of PV reference module was higher than the ambient temperature by 27oC but there is too small difference in temperature between the tracking PV module with the reference which ranged to 2oC, while the temperature of the CPV system was higher than reference by 37oC. The temperature of the PV module under mirror reflectors was lower than module combined with Aluminum reflectors by 3oC. As a result of arising of the temperature of CPV system in compare with PV reference module, the open circuit voltage was droop by 0.7 V, 0.5 V for PV module under mirror and Aluminum reflectors respectively. The reflectors increased the short circuit current values by 2.1 A, 2.6 A for PV module combined with mirror and Aluminum reflectors respectively. Accordingly the performance (as an average daily gain of output power) of the PV solar module was improved by using V-Trough CPV system, 44%, 34% by using Aluminum and mirror reflectors respectively.

Improve the performance of solar modules by reflectors

Solar energy is one of the most significant renewable energy sources, in both its applications thermal and photovoltaic, world needs. Iraq is one of the countries with the abundance of this type of energy, where annual solar activity reaches about 2000kWh/m2/year on the horizontal surface. In the present work a solar collectors with V-trough concentrator system were designed and fabricated with geometric concentration ratios two suns to get an extra electric output power. The experiment was carried out in Al-Zwraa Company in Baghdad. The main results indicated that the solar concentrator system caused to increase the short circuit current due to increase the amount of incident solar radiation on the solar modules, and thus increase in output power. As a comparison with reference module, the gain in output power, at solar noon, exceeded 48%. It can be concluded that the use of V-Trough concentrator system coupled with solar module systems can result in a favourable cost-benefit ratio.

Enhanced electrical performance in a solar photovoltaic module using V-trough concentrators

The electrical performance of a novel solar photovoltaic collector fabricated by lamination of silicon PV cells onto a copper metal sheet using EVA as the bond material and adding a single water channel underneath was further improved by using V-trough booster reflector mirrors. From the ray-tracing analysis, it was observed that under fixed tilt of 13°, the one-mirror arrangement even though of less concentration provides uniform illumination for seven months, whereas the two-mirror arrangement does not provide uniform illumination in any month except June. The non-uniform illumination on the solar photovoltaic collector due to different incidence angles throughout the day, can be minimized by increasing the length of the reflector mirrors by 2.82 times the length of the modified PV module. Experimental results show that due to the fixed tilt of the V-trough concentrator and the reflection losses on the glazing, the increase in electrical power was realized only for a duration of 90–120 min around solar noon in one-mirror arrangement and for about 60 min around solar noon in the two-mirror arrangement. The higher power output observed for the fixed tilt V-trough concentrator during peak noon conditions is favourable for peak noon demand such as air-conditioning, irrigation, etc.

Design and Performance Analysis of a V-Trough Photovoltaic Concentrator

Design and Performance Analysis of a V-Trough Photovoltaic Concentrator

Optimum design of V-trough concentrator for photovoltaic applications

This paper presents new simulation of a V-trough concentrator used with photovoltaic module. OptisWorks, an advanced ray tracing software was used to determine the optimum design of the V-trough concentrator. In this paper, the effects of V-trough geometric parameters such as slant height of the reflectors and vertex angle on the trough optical performance in terms of effective concentration ratio and irradiance distribution were investigated to determine the optimum design. In this simulation, a V-trough concentrator with four geometric concentration ratios (1.5×, 2×, 2.5×, and 3×) and three reflective materials (ideal reflector R100%, anodized aluminium R90%, and mirror R80%) were investigated. The simulation results of the effective concentration ratio using OptisWorks compared with published experimental showing good agreement with about 1.99% deviation. Results show that the optimum vertex angles of the V-trough concentrator for 1.5×, 2×, 2.5×, and 3× are 30°, 30°, 22°, and 19°, respectively.

Experimental investigations into low concentrating line axis solar concentrators for CPV applications

Solar photovoltaic conversion systems with integrated, low concentration ratio, non-imaging reflective concentrators, could be on south facing building roofs used to generate power at a lower cost than currently available proprietary systems. The experimental investigation presented by this research provides information on the optical and energy conversion characteristics of two geometrically equivalent non-imaging concentrators; a compound parabolic concentrator and a V-trough reflector. The aim was to investigate the assumption of uniform cell illumination when PV cells located on the receiver surface with their central axes are aligned parallel with the focal line of the line-axis concentrator. Solar radiation incident was measured at the aperture and the PV cell surface using respectively a pyranometer and photodiodes at six different collector tilt angles of 0°, 10°, 20°, 30°, 40° and 52°. The analysis of the collected experimental data presented demonstrated that the V-trough system had a more even distribution of solar radiation than the CPC and a higher optical concentration ratio (ratio of solar radiation incident on the aperture cover to that incident on the receiver) though the geometrical concentration ratio of the two collectors was equal to 2.2×. Also, the V-trough concentrator had an electrical power output up to 17.2% higher than the CPC system at a specific tilt angle of 30°. The V-trough had a consistently higher receiver plate temperature as it was reflecting larger quantities of solar radiation than the CPC. Over 17 consecutive typical summer days’ similar performance was observed over the range of tilt angles studied. The development of V-trough concentrators should be preferred due to higher power production, reduced complexity, increased uniformity of illumination and lower manufacturing costs compared to CPCs.

WITHDRAWN: V-trough concentrator with integrated cooling for performance enhancement of rooftop PV in arid and semi-arid regions of India

WITHDRAWN: V-trough concentrator with integrated cooling for performance enhancement of rooftop PV in arid and semi-arid regions of India

Photovoltaic and disinfection performance study of a hybrid photovoltaic-solar water disinfection system

It is the first time that flat PV (photovoltaic) cells were integrated with SODIS (solar water disinfection) to be an access to the clean drinkable water and the renewable electricity. The disinfection and photovoltaic performance of the system was evaluated by the disinfection of Escherichia coli (E. coli) and Salmonella. In order to enhance the SODIS process, a V-trough concentrator and low concentration H2O2 were adopted. The treatment time required for 8 L water that reached completely disinfection was 1.25 h and 2.5 h for the inactivation of E. coli and Salmonella respectively, when using the V-trough concentrator and 5 mg L−1 H2O2 simultaneously. Therefore, E. coli seems not to be a suitable bacteria indicator for SODIS. The temperature of the PV module decreases significantly because of the additional water layer, so that the power generation efficiency is improved. Although the water layer on the PV module can both reflect and absorb light, the output power of the PV module with a V-trough concentrator is about 43 W (the reference is 26.1 W), which is much higher than the whole system power consumption. Therefore, the excess power can be used for other applications.

Analysis of a photovoltaic-electrolyser direct-coupling system with a V-trough concentrator

Hydrogen is a clean energy carrier for energy storage which is essential to solar system for continuous energy output. A promising method to store solar energy as hydrogen energy is by using photovoltaic-electrolyser (PVE) system. In this investigation, the operation of a PVE system with V-trough concentrator was studied experimentally and numerically. The V-trough concentrator was optimized and the daily average concentration ratio reaches about 1.9. A mathematical model including the sub models for irradiation flux pattern, PV array and electrolyser was established to analyze the characteristics of the system and it was verified experimentally. The results show that the utilization of V-trough concentrator makes PVE system work more efficiently with the same PV array. In this study, the conversion efficiency of solar energy to hydrogen energy was increased from 5.62% to 6.18% and the hydrogen production was doubled.

White butterflies as solar photovoltaic concentrators.

Man’s harvesting of photovoltaic energy requires the deployment of extensive arrays of solar panels. To improve both the gathering of thermal and photovoltaic energy from the sun we have examined the concept of biomimicry in white butterflies of the family Pieridae. We tested the hypothesis that the V-shaped posture of basking white butterflies mimics the V-trough concentrator which is designed to increase solar input to photovoltaic cells. These solar concentrators improve harvesting efficiency but are both heavy and bulky, severely limiting their deployment. Here, we show that the attachment of butterfly wings to a solar cell increases its output power by 42.3%, proving that the wings are indeed highly reflective. Importantly, and relative to current concentrators, the wings improve the power to weight ratio of the overall structure 17-fold, vastly expanding their potential application. Moreover, a single mono-layer of scale cells removed from the butterflies’ wings maintained this high reflectivity showing that a single layer of scale cell-like structures can also form a useful coating. As predicted, the wings increased the temperature of the butterflies’ thorax dramatically, showing that the V-shaped basking posture of white butterflies has indeed evolved to increase the temperature of their flight muscles prior to take-off.

Natural convection heat transfer in V-trough solar concentrators

The use of V-trough concentrators offers a simple approach to increasing the radiation incident on a solar receiver; this is particularly useful for increasing the temperature in thermal systems. However in order to accurately predict the performance of thermal systems under concentrated radiation, there is a need to understand the heat loss from them. This study experimentally shows that, for a laterally and longitudinally inclined enclosed V-trough concentrator, the natural convection heat loss can be predicted using an equation of the form Nu=aRab for Rayleigh numbers between 2×103 and 1×108. It is suggested that the relationship is a good representation of heat transfer in enclosed V-trough concentrators under most practical orientations, and thus lends itself for implementation into design models for V-trough concentrators.

Case study of a grid connected with a battery photovoltaic system: V-trough concentration vs. single-axis tracking

Photovoltaic systems (PVSs) combined with either some form of storage, such as a battery energy storage system (BESS), or direct load control, can play a crucial role in achieving a more economical operation of the electric utility system while enhancing its reliability with additional energy sources. At the same time, it is also important to use cost-effective PV solutions. In this context, a low-concentration PVS (CPVS) is analysed as a feasible alternative. This paper, present a case study of a complex PVS, composed of two PVSs, a storage system (BEES) and an inverter that allows the system to operate in both the island and grid-connected modes. The first PVS, is a 2.76-kWp single-axis tracking system (azimuth) with modules facing south and tilted 30°, while the second PVS is a dual-axis tracking system, rated 860Wp, consisting of a concentrator at the flat mirrors (DoubleSun® Four). The system is installed on the roof of the main building of the “ITIS Marconi” school (Italy). A detailed description of the system is provided, and preliminary operating data are presented and discussed. The efficiencies of the PV systems are calculated and measured to evaluate the cost effectiveness of a low-concentration system.