Study on the Optical Properties of Triangular Cavity Absorber for Parabolic Trough Solar Concentrator

A theoretical analytical method for optical properties of cavity absorber was proposed in this paper and the optical design software TracePro was used to analyze the optical properties of triangular cavity absorber. It was found that the optimal optical properties could be achieved with appropriate aperture width, depth-to-width ratio, and offset distance from focus of triangular cavity absorber. Based on the results of orthogonal experiment, the optimized triangular cavity absorber was designed. Results showed that the standard deviation of irradiance and optical efficiency of optimized designed cavity absorber were 30528 W/m2and 89.23%, respectively. Therefore, this study could offer some valuable references for designing the parabolic trough solar concentrator in the future.

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Solar Concentrator Consisting of Multiple Aspheric Reflectors

Energies ◽

10.3390/en12214038 ◽

2019 ◽

Vol 12 (21) ◽

pp. 4038

Author(s):

Guobin Cao ◽

Hua Qin ◽

Rajan Ramachandran ◽

Bo Liu

Keyword(s):

Focal Plane ◽

Concentration Ratio ◽

Optical Design ◽

Pso Algorithm ◽

Solar Concentrator ◽

Coordinate Transformations ◽

Swarm Optimization ◽

Spot Radius ◽

Design Software ◽

Tracing Method

This paper presents an off-axis-focused solar concentrator system consisting of 190 aspheric reflectors, where the aperture radius of each reflector is 10 cm, and vertices of all reflectors are orderly arranged in the same plane. The aspheric parameters controlling the curvature of the reflectors are determined using coordinate transformations and the particle swarm optimization (PSO) algorithm. Based on these aspheric parameters, the light distribution of focal plane was calculated by the ray tracing method. The analyses show that the designed concentrator system has a spot radius of less than 1 cm and the concentration ratio over 3300:1 is achieved using only one reflection. The design results have been verified with the optical design software Zemax.

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Investigation on the Optical Design and Performance of a Single-Axis-Tracking Solar Parabolic trough Collector with a Secondary Reflector

Sustainability ◽

10.3390/su13179918 ◽

2021 ◽

Vol 13 (17) ◽

pp. 9918

Author(s):

Chinnasamy Subramaniyan ◽

Jothirathinam Subramani ◽

Balasubramanian Kalidasan ◽

Natarajan Anbuselvan ◽

Thangaraj Yuvaraj ◽

...

Keyword(s):

Incidence Angle ◽

Optical Design ◽

Operating Conditions ◽

Optical Performance ◽

Ambient Conditions ◽

Parabolic Trough ◽

Tracking Errors ◽

Optical Efficiency ◽

Collector System ◽

And Performance

The design of solar concentrating collectors for the effective utilization of solar energy is a challenging condition due to tracking errors leading to different divergences of the solar incidence angle. To enhance the optical performance of solar parabolic trough collectors (SPTC) under a diverged solar incidence angle, an additional compound parabolic concentrator (CPC) is introduced as a secondary reflector. SPTC with CPC is designed and modeled for a single axis-tracking concentrating collector based on the local ambient conditions. In this work, the optical performance of the novel SPTC system with and without a secondary reflector is investigated using MATLAB and TRACEPRO software simulations for various tracking errors. The significance parameters such as the solar incidence angle, aperture length, receiver tube diameter, rim angle, concentration ratio, solar radiation, and absorbed flux are analyzed. The simulation results show that the rate of the absorbed flux on the receiver tube is significantly improved by providing the secondary reflector, which enhances the optical efficiency of the collector. It is found that the optical efficiency of the SPTC with a secondary reflector is 20% higher than the conventional collector system for a solar incidence angle of 2°. This work can effectively direct the choice of optimal secondary reflectors for SPTC under different design and operating conditions.

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High Concentration Photovoltaics (HCPV) with Diffractive Secondary Optical Elements

Photonics ◽

10.3390/photonics6020068 ◽

2019 ◽

Vol 6 (2) ◽

pp. 68 ◽

Cited By ~ 9

Author(s):

Furkan Sahin ◽

Musa Yılmaz

Keyword(s):

Low Cost ◽

Optical Design ◽

Chromatic Aberration ◽

High Energy ◽

Solar Concentrator ◽

High Concentration ◽

Acceptance Angle ◽

Optical Elements ◽

Optical Efficiency ◽

Single Material

Multi-junction solar cells can be economically viable for terrestrial applications when operated under concentrated illuminations. The optimal design of concentrator optics in high concentration photovoltaics (HCPV) systems is crucial for achieving high energy conversion. At a high geometric concentration, chromatic aberration of the primary lens can restrict the optical efficiency and acceptance angle. In order to correct chromatic aberration, multi-material, multi-element refractive elements, hybrid refractive/diffractive elements, or multi-element refractive and diffractive systems can be designed. In this paper, the effect of introducing a diffractive surface in the optical path is analyzed. An example two-stage refractive and diffractive optical system is shown to have an optical efficiency of up to 0.87, and an acceptance angle of up to ±0.55° with a 1600× geometric concentration ratio, which is a significant improvement compared to a single-stage concentrator system with a single material. This optical design can be mass-produced with conventional fabrication methods, thus providing a low-cost alternative to other approaches, and the design approach can be generalized to many other solar concentrator systems with different cell sizes and geometric concentration ratios.

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Optical Simulation and Experimental Verification of a Fresnel Solar Concentrator with a New Hybrid Second Optical Element

International Journal of Photoenergy ◽

10.1155/2016/4970256 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Guiqiang Li ◽

Yi Jin

Keyword(s):

Optical Properties ◽

Concentration Ratio ◽

Flux Distribution ◽

Deflection Angle ◽

Optical Element ◽

Fresnel Lens ◽

Optical Simulation ◽

Solar Concentrator ◽

Optical Efficiency ◽

Solar Concentrators

Fresnel solar concentrator is one of the most common solar concentrators in solar applications. For high Fresnel concentrating PV or PV/T systems, the second optical element (SOE) is the key component for the high optical efficiency at a wider deflection angle, which is important for overcoming unavoidable errors from the tacking system, the Fresnel lens processing and installment technology, and so forth. In this paper, a new hybrid SOE was designed to match the Fresnel solar concentrator with the concentration ratio of 1090x. The ray-tracing technology was employed to indicate the optical properties. The simulation outcome showed that the Fresnel solar concentrator with the new hybrid SOE has a wider deflection angle scope with the high optical efficiency. Furthermore, the flux distribution with different deviation angles was also analyzed. In addition, the experiment of the Fresnel solar concentrator with the hybrid SOE under outdoor condition was carried out. The verifications from the electrical and thermal outputs were all made to analyze the optical efficiency comprehensively. The optical efficiency resulting from the experiment is found to be consistent with that from the simulation.

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Influence of a Thermal Pad on Selected Parameters of Power LEDs

Energies ◽

10.3390/en13143732 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3732

Author(s):

Krzysztof Górecki ◽

Przemysław Ptak ◽

Tomasz Torzewicz ◽

Marcin Janicki

Keyword(s):

Optical Properties ◽

Thermal Resistance ◽

Optical Power ◽

Junction Temperature ◽

Operating Parameters ◽

Cold Plate ◽

Optical Efficiency ◽

Forward Current ◽

Measurement Results ◽

Set Up

This paper is devoted to the analysis of the influence of thermal pads on electric, optical, and thermal parameters of power LEDs. Measurements of parameters, such as thermal resistance, optical efficiency, and optical power, were performed for selected types of power LEDs operating with a thermal pad and without it at different values of the diode forward current and temperature of the cold plate. First, the measurement set-up used in the paper is described in detail. Then, the measurement results obtained for both considered manners of power LED assembly are compared. Some characteristics that illustrate the influence of forward current and temperature of the cold plate on electric, thermal, and optical properties of the tested devices are presented and discussed. It is shown that the use of the thermal pad makes it possible to achieve more advantageous values of operating parameters of the considered semiconductor devices at lower values of their junction temperature, which guarantees an increase in their lifetime.

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Optical design of a flat-facet solar concentrator

Solar Energy ◽

10.1016/j.solener.2012.03.007 ◽

2012 ◽

Vol 86 (6) ◽

pp. 1962-1966 ◽

Cited By ~ 13

Author(s):

Zhiqiang Liu ◽

Justin Lapp ◽

Wojciech Lipiński

Keyword(s):

Optical Design ◽

Solar Concentrator

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Comparison of Two Linear Collectors in Solar Thermal Plants: Parabolic Trough vs Fresnel

ASME 2011 5th International Conference on Energy Sustainability, Parts A, B, and C ◽

10.1115/es2011-54312 ◽

2011 ◽

Cited By ~ 9

Author(s):

A. Giostri ◽

M. Binotti ◽

P. Silva ◽

E. Macchi ◽

G. Manzolini

Keyword(s):

Power Plants ◽

Thermal Power ◽

Solar Thermal ◽

Heat Transfer Fluid ◽

Steam Generation ◽

Parabolic Trough ◽

Research Activity ◽

Optical Efficiency ◽

Synthetic Oil ◽

Yearly Average

Parabolic trough can be considered the state of the art for solar thermal power plants thanks to the almost 30 years experience gained in SEGS and, recently, Nevada Solar One plants in US and Andasol plants in Spain. One of the major issues that limits the wide diffusion of this technology is the high investment cost of the solar field and, particularly, of the solar collector. For this reason, since several years research activity has been trying to develop new solutions with the aim of cost reduction. This work compares commercial Fresnel technology with conventional parabolic trough plant based on synthetic oil as heat transfer fluid at nominal conditions and evaluates yearly average performances. In both technologies, no thermal storage system is considered. In addition, for Fresnel, a Direct Steam Generation (DSG) case is investigated. Performances are calculated by a commercial code, Thermoflex®, with dedicated component to evaluate solar plant. Results will show that, at nominal conditions, Fresnel technology have an optical efficiency of 67% which is lower than 75% of parabolic trough. Calculated net electric efficiency is about 19.25%, while parabolic trough technology achieves 23.6%. In off-design conditions, the gap between Fresnel and parabolic trough increases because the former is significantly affected by high radiation incident angles. The calculated sun-to-electric annual average efficiency for Fresnel plant is 10.2%, consequence of the average optical efficiency of 38.8%, while parabolic trough achieve an overall efficiency of 16%, with an optical one of 52.7%. An additional case with Fresnel collector and synthetic oil outlines differences among investigated cases. Finally, because part of performance difference between PT and Fresnel is simple due to different definitions, additional indexes are introduced in order to make a consistent comparison.

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Field test of thermoelectric generator using parabolic trough solar concentrator for power generation

10.1063/1.5028104 ◽

2018 ◽

Author(s):

Rommel R. Viña ◽

Feliciano B. Alagao

Keyword(s):

Power Generation ◽

Field Test ◽

Thermoelectric Generator ◽

Solar Concentrator ◽

Parabolic Trough

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Design and Fabrication of Absorptive/Reflective Crossed CPC PV/T System

Designs ◽

10.3390/designs2030029 ◽

2018 ◽

Vol 2 (3) ◽

pp. 29

Author(s):

Muhsin Aykapadathu ◽

Mehdi Nazarinia ◽

Nazmi Sellami

Keyword(s):

Numerical Control ◽

Solar Concentrator ◽

Cnc Milling ◽

Acceptance Angle ◽

Optical Efficiency ◽

Compound Parabolic Concentrator ◽

Building Integrated Photovoltaic ◽

New Generation ◽

Experimental Rig ◽

T System

A crossed compound parabolic concentrator (CCPC) is a non-imaging concentrator which is a modified form of a circular 3D compound parabolic concentrator (CPC) obtained by orthogonal intersection of two 2D CPCs that have an optical efficiency in line with that of 3D CPC. The present work is about the design and fabrication of a new generation of solar concentrator: the hybrid photovoltaic (PV)/thermal absorptive/reflective CCPC module. The module has a 4× CCPC structure truncated to have a concentration of 3.6× with a half acceptance angle of 30°. Furthermore, an experimental rig was also fabricated to test the performance of the module and its feasibility in real applications such as building-integrated photovoltaic (BIPV). 3D printing and Computer Numerical Control (CNC) milling technologies were utilized to manufacture the absorber and reflective parts of the module.

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