Academia.edu no longer supports Internet Explorer.
To browse Academia.edu and the wider internet faster and more securely, please take a few seconds to upgrade your browser.
Non-tracking planar concentrators are a low-cost method of increasing the performance of traditional solar photovoltaic (PV) systems. This paper presents new methodologies for properly modeling this type of system design and experimental results using a bi-directional reflectance function (BDRF) of non-ideal surfaces rather than traditional geometric optics. This methodology allows for the evaluation and optimization of specular and non-specular reflectors in planar concentration systems. In addition, an outdoor system has been shown to improve energy yield by 45% for a traditional flat glass module and by 40% for a prismatic glass crystalline silicon module when compared to a control module at the same orientation. When compared to a control module set at the optimal tilt angle for this region, the energy improvement is 18% for both system. Simulations show that a maximum increase of 30% is achievable for an optimized system located in Kingston, ON using a reflector with specular reflection and an integrated hemispherical reflectance of 80%. This validated model can be used to optimize reflector topology to identify the potential for increased energy harvest from both existing PV and new-build PV assets.
Photovoltaic Specialists Conference (PVSC), 2013 IEEE 39th,
Photovoltaic System Performance Enhancement With Non-Tracking Planar Concentrators: Experimental Results and BDRF Based Modelling2013 •
Non-tracking planar concentrators are a low-cost method of increasing the performance of traditional solar photovoltaic (PV) systems. In this study such an outdoor system has been shown to improve energy yield by 45% for a traditional flat glass module and by 35% for a prismatic glass crystalline silicon module. In addition, this paper presents new methodologies for properly modelling this type of system design and experimental results using a bi-directional reflectance function (BDRF) of non-ideal surfaces rather than traditional geometric optics. This methodology allows for the evaluation and eventual optimization of specular and non-specular reflectors in planar concentration systems.
In this study, a theoretical analysis of a solar field augmented by a fixed reflector placed in the front between the top of the preceding row and the bottom of the succeeding row is presented. An analytical model has been developed and used to estimate the solar irradiation. The analytical model is based on the anisotropic sky model, assuming an infinite length of collector and reflector rows. A simulation has been carried out in order to figure out the behavior of the solar field and to find the optimum design parameters of the solar field leading to a maximum solar energy augmentation. The results obtained are depicted synoptically as a relationship between the solar field design parameters and the latitude angle, and this presentation enables us to determine the optimum design parameters in order to achieve the intended percentage improvement of solar radiation incident on the solar field rows at any location on the Northern hemisphere, which presents the novelty of this research. Also we have introduced a new parameter named " the effective height of the collector " , which presents the portion of the collector's height illuminated by the reflector. This parameter is very important especially in case of PV solar fields, because it determines the domain of the concentrated solar energy over the surface of the PV panel.
Solar Energy Materials and Solar Cells
Optimisation of reflector and module geometries for stationary, low-concentrating, façade-integrated photovoltaic systems2007 •
2001 •
The light collection properties of PhoCUS C-Module photovoltaic concentration units have been investigated by realizing a rugged “Mock-up” containing the primary refractive optics, a secondary optical element (SOE) and a receiver. To independently investigate the sole collection efficiency of the optical unit, the receiver was realized by an integrating sphere equipped with a photodetector, able to collect, with known efficiency, all the radiation reaching the receiver area. To investigate the optical efficiency of the whole C-Module photovoltaic concentration unit, a concentration silicon cell, pre-viously tested in the PhoCUS C-Modules, was used as receiver. Two methods were applied for the optical measurements, the conventional “direct” method using a parallel beam with solar divergence to irradiate the front side of concentrator, and the “inverse” method using a lambertian source applied in place of the concentrating cell in order to operate the concentrator in the reverse way.
International Journal of Optics and Applications
Modelling of Compound Parabolic Concentrators for Photovoltaic Applications2013 •
The collection properties of nonimaging "Rondine ® " PV solar concentrators are investigated by indoor measurements of the angle-resolved optical efficiency. We illustrate two different methods to draw the optical efficiency curve. The first one, briefly called as "direct method", is performed by producing a uniform and collimated beam of known flux impinging on the input aperture of the concentrator at different incidence angles, and by measuring the flux collected at the exit aperture. The second method, called "inverse method", is based on a reverse illumination procedure, whereby a lambertian diffused light is produced at the exit aperture of the concentrator, and the radiance of the beam transmitted backwards from the input aperture is measured at different directions in space. The obtained results are similar for the two methods, but the "inverse method" is largely to be preferred for the simplicity of the experimental apparatus and the ...
Proceedings of the World Renewable Energy Congress – Sweden, 8–13 May, 2011, Linköping, Sweden
Using Structured Aluminum Reflectors in Flux Scattering on Module Performance2011 •
The photons in the solar spectrum with energy equal to or higher than the band gap energy of the solar cell material are potentially useful for photo electricity. However, as most of the commercial solar cells have negative thermal coefficients; during operation, the unused photons cause thermal losses in these solar cells, and affect their electrical conversion efficiency. To overcome these losses, combined Photovoltaic Thermal systems (PVT) are developed. In these systems, heat is extracted from the PV module to improve its performance. This extracted heat is used separately for thermal applications. Thus, the system gives both electrical and thermal output simultaneously. Several such PVT systems have been reported in the past. In the current study, an inverted trapezoidal flume shaped PVT system is designed. The system is equipped with the flat mirror reflectors from all sides. Water is used as working medium to extract the heat from the PV module. The performance of the system is analyzed experimentally at Nagpur [21° N, 79° E] for different operating conditions. The experimental results had shown significant improvement in the electrical efficiency of PV module. Maximum average electrical efficiency and maximum overall efficiency of the system were found to be 10.42 and 62% respectively. Constructional details of the system and the performance analysis are discussed in this article. INTRODUCTION The operating temperature of solar cell plays an important role in the photovoltaic energy conversion process. The output of PV cells decreases as the cell temperature increases. PV module efficiency is usually inversely proportional to the operating cell temperature [1, 2]. In the case of mono-crystalline silicon cell, the efficiency decreases by 0.45% for the unit rise in temperature [3-5]. A typical solar PV module converts 6-20% of total incident solar radiation into electricity and the rest of incident radiations get converted into undue heat, which significantly raises the temperature of PV module [6, 7]. This undue heat can be extracted by circulating cooling medium in contact with the PV module. Such a system is known as Pho-tovoltaic thermal (PVT) system. This system facilitates the conversion of solar radiation into heat and electricity simultaneous. The PVT systems have higher efficiency compared to individual PV and thermal systems [8]. The PVT systems are broadly classified on the basis of heat extraction arrangement, working media, and end applications. Further, the PVT systems can also be classified based on non-concentration and concentration arrangements of radiations.
Solar Energy Materials and Solar Cells
Angular characterization of low concentrating PV–CPC using low-cost reflectors2008 •
2006 •
Progress in Photovoltaics: Research and Applications
Reflector materials for two-dimensional low-concentrating photovoltaic systems: the effect of specular versus diffuse reflectance on the module efficiency2005 •
Solar Energy Materials and Solar Cells
Mitigating the non-uniform illumination in low concentrating CPCs using structured reflectors2009 •
2015 •
Progress in Photovoltaics
Role of radiation-hard solar cells in minimizing the costs of global satellite communication systems1996 •
AIP Conference Proceedings 2144, 030008 (2019)
Study the Performance of V-Trough PV Solar System with 1.5123078 fadhil karbalaSolar energy materials and solar cells
Power losses in an asymmetric compound parabolic photovoltaic concentrator2007 •
International Journal of Optics and Applications
Optical Simulation of PV Solar Concentrators by two Inverse Characterization Methods2012 •
2001 •
Energy and Buildings
Optimal position of flat plate reflectors of solar thermal collector2012 •
Third International ISES Europe …
Optical properties of SnOx: F/Al2O3/Al solar selective reflector surfaces2000 •
Applied Energy
Influence of reflectance from flat aluminum concentrators on energy efficiency of PV/Thermal collector2010 •
Physica Status Solidi a Applications and Materials Science
3D photonic crystal intermediate reflector for micromorph thin-film tandem solar cell2008 •
Renewable and Sustainable Energy Reviews
Concentrating photovoltaic thermal (CPVT) collectors and systems: Theory, performance assessment and applications2018 •