Browsing by Author "Hong, Hwen-Fen"

Now showing 1 - 7 of 7

Efficiency evaluation of a hybrid miniaturized concentrated photovoltaic for harvesting direct/diffused solar light
(2019-03-01)
Tsao, Wei-Chen
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Zeng, Qiu-Chun
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Yeh, Yu-Hsiang
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Tsai, Chih-Hung
;
Hong, Hwen-Fen
In this paper, a miniaturized concentrator photovoltaic (CPV) system is experimentally demonstrated based on a hot embossing silicone lens array with a size of 2 cm x 2 cm. Owing to the small size of the lens array, the total track of the CPV system can be as small as 4 cm. Consequently, the weight of the CPV system can be much lower than conventional bulky CPV system. For harvesting the diffuse solar radiation, perovskite solar cells are mounted adjacent to a multi junction solar cell. Theoretically, the short-circuit current of the CPV system can be enhanced from 48.1 to 85.5 mA for gamma = 0.7. The enhancement can be much higher for off-normal incident light. This kind of hybrid CPV system will be useful for cloudy weather and also useful for compensating the loss caused by the miss-alignment of the tracking module.
High concentration and homogenized Fresnel lens without secondary optics element
(2011-09-01)
Pan, Jui-Wen
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Huang, Jiun-Yang
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Wang, Chih-Ming
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Hong, Hwen-Fen
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Liang, Yi-Ping
In this paper, we design a single concentrator to homogenize and concentrate the solar energy. The proposed concentrator only consisted of an array of refraction prisms. In order to homogenize the irradiance, all pitches of the Fresnel concentrator focus on the different position of the receiver. Finally, the Fresnel lens that achieves the uniformity of U is 14.6. An acceptance angle of 0.305 degrees is achieved without using additional secondary optics. Full Width at Half Maximum (FWHM) of illumination distribution is 1.4 mm. (C) 2011 Elsevier B.V. All rights reserved.
Improved Efficiency of a Large-Area Cu(In,Ga)Se-2 Solar Cell by a Nontoxic Hydrogen-Assisted Solid Se Vapor Selenization Process
(2014-04-09)
Wu, Tsung-Ta
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Hu, Fan
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Huang, Jyun-Hong
;
Chang, Chia-ho
;
Lai, Chih-chung
A nontoxic hydrogen-assisted solid Se vapor selenization process (HASVS) technique to achieve a large-area (40 X 30 cm(2)) Cu(In,Ga)Se-2 (CIGS) solar panel with enhanced efficiencies from 7.1 to 10.8% (12.0% for active area) was demonstrated. The remarkable improvement of efficiency and fill factor comes from improved open circuit voltage (V-oc) and reduced dark current due to (1) decreased interface recombination raised from the formation of a widened buried homojunction with n-type Cd-cu participation and (2) enhanced separation of electron and hole carriers resulting from the accumulation of Na atoms on the surface of the CIGS film. The effects of microstructural, compositional, and electrical characteristics with hydrogen-assisted Se vapor selenization, including interdiffusion of atoms and formation of buried homojunction, were examined in detail. This methodology can be also applied to CIS (CuInSe2) thin film solar cells with enhanced efficiencies from 5.3% to 8.5% (9.4% for active area) and provides a facile approach to improve quality of CIGS and stimulate the nontoxic progress in the large scale CIGS PV industry.
Nine-sector three-stage Fresnel lens concentrator
(2019-01-01)
Chen, Yong-Da
;
Tu, Shin-Han
;
Hong, Hwen-Fen
;
Chen, Chun-Yi
;
Pan, Jui-Wen
In this paper, we design a three-stage Fresnel lens concentrator with a low f number. The proposed concentrator consists of a primary optical element (POE) and a second optical element (SOE). The nine-sector three-stage Fresnel lens is composed of three types of triangular prisms: the refractive triangular prism, single total internal reflection triangular prism, and double total internal reflection triangular prism. In order to increase the uniformity and acceptance angle of the POE coupled to the SOE, the SOE is also divided into nine sectors. Finally, it is found that this nine-sector three-stage Fresnel lens concentrator can achieve a concentration ratio of 1000x; the uniformity is 25.8, optical efficiency is 81.8%, f number is 0.46, and acceptance angle is +/- 0.73 degrees. (C) 2018 Optical Society of America
Nine-sector three-stage Fresnel lens concentrator (vol 58, pg 122, 2019)
(2019-02-20)
Chen, Yong-Da
;
Tu, Sheng Han
;
Hong, Hwen-Fen
;
Chen, Chun-Yi
;
Pan, Jui-Wen
Performance comparison of III-V//Si and III-V//InGaAs multi-junction solar cells fabricated by the combination of mechanical stacking and wire bonding
(2019-03-13)
Kao, Yu-Cheng
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Chou, Hao-Ming
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Hsu, Shun-Chieh
;
Lin, Albert
;
Lin, Chien-Chung
The integration of III-V and Si multi-junction solar cells as photovoltaic devices has been studied in order to achieve high photovoltaic conversion efficiency. However, large differences in the coefficients of thermal expansion and the lattice parameters of GaAs, Si, and InGaAs have made it difficult to obtain high-efficiency solar cells grown as epilayers on Si and InP substrates. In this paper, two types of devices, including GaInP/GaAs stacked on Si (GalnP/GaAs//Si) and GaInP/GaAs stacked on InGaAs (GaInP/GaAs//InGaAs), are fabricated via mechanical stacking and wire bonding technologies. Mechanically stacked GaInP/GaAs//Si and GaInP/GaAsllInGaAs triple-junction solar cells are prepared via glue bonding. Current-voltage measurements of the two samples are made at room temperature. The short-circuit current densities of the GaInP/GaAs//Si and GaInP/GaAs//InGaAs solar cells are 13.37 and 13.66 mA/cm(2), while the open-circuit voltages of these two samples are measured to be 2.71 and 2.52V, respectively. After bonding the GaInP/GaAs dual-junction with the Si and InGaAs solar cells, the conversion efficiency is relatively improved by 32.6% and 30.9%, respectively, compared to the efficiency of the GaInP/GaAs dual-junction solar cell alone. This study demonstrates the high potential of combining mechanical stacked with wire bonding and ITO films to achieve high conversion efficiency in solar cells with three or more junctions.
Single stage transmission type broadband solar concentrator
(2010-06-21)
Wang, Chih-Ming
;
Huang, Hung-I
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Pan, J. W.
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Kuo, Hung-Zen
;
Hong, Hwen-Fen
In this paper, a single stage solar cell concentrator is designed and discussed. The proposed concentrator consists of refraction prisms and total internal reflection prisms in the inner and outer areas, respectively. In order to compensate for dispersion, all odd zones gather the light onto the - D position, while all even zones gather the light onto the + D position. Finally, the hybrid concentrator achieves optical efficiency of 89.8% for normally incident light without an antireflection coating. An acceptance angle of +/- 0.78 degrees at 1dB loss is achieved without using additional secondary optics. In addition, the fabrication tolerance is also analyzed. (C) 2010 Optical Society of America