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Title: Optical study of a spectrum splitting solar concentrator based on a combination of a diffraction grating and a Fresnel lens

Abstract

This paper presents recent improvements of our new solar concentrator design for space application. The concentrator is based on a combination of a diffraction grating (blazed or lamellar) coupled with a Fresnel lens. Thanks to this diffractive/refractive combination, this optical element splits spatially and spectrally the light and focus approximately respectively visible light and IR light onto electrically independent specific cells. It avoid the use of MJs cells and then also their limitations like current matching and lattice matching conditions, leading theoretically to a more tolerant system. The concept is reminded, with recent optimizations, ideal and more realistic results, and the description of an experimental realization highlighting the feasibility of the concept and the closeness of theoretical and experimental results.

Authors:
;  [1];  [2]; ;  [1]
  1. Centre Spatial de Liège, Avenue du Pré-Aily, 4031 Angleur (Belgium)
  2. (B5a), 4000 Liège (Belgium)
Publication Date:
OSTI Identifier:
22489015
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1679; Journal Issue: 1; Conference: CPV-11: 11. international conference on conventrator photovoltaictaic systems, Aix-les-Bains (France), 13-15 Apr 2015; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; CURRENTS; DESIGN; DIFFRACTION; DIFFRACTION GRATINGS; FRESNEL LENS; OPTIMIZATION; REFRACTION; SOLAR CELLS; SOLAR CONCENTRATORS; VISIBLE RADIATION

Citation Formats

Michel, Céline, E-mail: cmichel@ulg.ac.be, Habraken, Serge, Hololab, University of Liège, Allée du 6 Août, 17, Loicq, Jérôme, and Thibert, Tanguy. Optical study of a spectrum splitting solar concentrator based on a combination of a diffraction grating and a Fresnel lens. United States: N. p., 2015. Web. doi:10.1063/1.4931539.
Michel, Céline, E-mail: cmichel@ulg.ac.be, Habraken, Serge, Hololab, University of Liège, Allée du 6 Août, 17, Loicq, Jérôme, & Thibert, Tanguy. Optical study of a spectrum splitting solar concentrator based on a combination of a diffraction grating and a Fresnel lens. United States. doi:10.1063/1.4931539.
Michel, Céline, E-mail: cmichel@ulg.ac.be, Habraken, Serge, Hololab, University of Liège, Allée du 6 Août, 17, Loicq, Jérôme, and Thibert, Tanguy. Mon . "Optical study of a spectrum splitting solar concentrator based on a combination of a diffraction grating and a Fresnel lens". United States. doi:10.1063/1.4931539.
@article{osti_22489015,
title = {Optical study of a spectrum splitting solar concentrator based on a combination of a diffraction grating and a Fresnel lens},
author = {Michel, Céline, E-mail: cmichel@ulg.ac.be and Habraken, Serge and Hololab, University of Liège, Allée du 6 Août, 17 and Loicq, Jérôme and Thibert, Tanguy},
abstractNote = {This paper presents recent improvements of our new solar concentrator design for space application. The concentrator is based on a combination of a diffraction grating (blazed or lamellar) coupled with a Fresnel lens. Thanks to this diffractive/refractive combination, this optical element splits spatially and spectrally the light and focus approximately respectively visible light and IR light onto electrically independent specific cells. It avoid the use of MJs cells and then also their limitations like current matching and lattice matching conditions, leading theoretically to a more tolerant system. The concept is reminded, with recent optimizations, ideal and more realistic results, and the description of an experimental realization highlighting the feasibility of the concept and the closeness of theoretical and experimental results.},
doi = {10.1063/1.4931539},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1679,
place = {United States},
year = {Mon Sep 28 00:00:00 EDT 2015},
month = {Mon Sep 28 00:00:00 EDT 2015}
}
  • A transmittance-optimized linear Fresnel lens solar concentrator has been developed. The optical performance of the lens has been analytically predicted, using the method of cone optics, to define the radiant flux profile in the focal plane. Also, the optical performance of the lens has been experimentally determined, using a focal plane radiant flux scanner, under actual solar illumination. A brief description of the lens, its predicted performance, and its measured performance is presented.
  • Fresnel lenses are widely used in concentrating photovoltaic (CPV) systems as a primary optical element. They focus sunlight on small solar cells or on the entrance apertures of secondary optical elements. A Fresnel lens consists of several prism rings and diffraction by these prism rings is unavoidable. Some of the light that would reach a designated target area according to geometric optics will miss it due to diffraction. This diffraction loss may be of relevant magnitude for CPV applications. The results of published analytical calculations are evaluated, discussed, and compared to computer simulations and measurements.
  • Experiments were performed to gain information on the behavior of the 3M circular fresnel lens as a solar concentrator. A simulation was constructed to model that behavior. From consideration of the results of this work, it can be said that the lens is an inefficient concentrator with losses that begin at 20 and rise to about 80% as the focal distance decreases. However, the lens is capable and adequate for low concentration purposes with photovoltaic systems. The most attractive aspects of using this lens as a solar concentrator are its availability and its potential low cost.
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  • Fresnel lenses have been used for years as solar concentrators in a variety of applications. Several variables affect the final design of these lenses including: lens diameter, image spot distance from the lens, and bandwidth focused in the image spot. Defining the image spot as the geometrical optics circle of least confusion, a set of design equations has been derived to define the groove angles for each groove on the lens. These equations allow the distribution of light by wavelength within the image spot to be calculated. Combining these equations with the blackbody radiation equations power, power distribution, and fluxmore » within the image spot can be calculated. In addition, equations have been derived to design a lens to produce maximum flux in a given spot size. Using these equations, a lens may be designed to optimize the spot energy concentration for given energy source.« less