Measurements of the Electrical Incidence Angle Modifiers of an Asymmetrical Photovoltaic/Thermal Compound Parabolic Concentrating-Collector

Bernardo Ricardo, Davidsson Henrik, Gentile Niko, Gomes João, Gruffman Christian, Chea Luis, Mumba Chabu, Karlsson Björn

Division of Energy Engineering, M?lardalen University, V?ster?s, Sweden.
Energy and Building Design, Lund University, Lund, Sweden.
Finsun AB, ?lvkarleby, Sweden.
Solarus Sunpower AB, Stockholm, Sweden.
Universidade Eduardo Mondlane, Maputo, Mozambique.
University of Zambia, Lusaka, Zambia.

DOI: 10.4236/eng.2013.51B007                

Abstract

Reflector edges, sharp acceptance angles and by-pass diodes introduce large variations in the electrical performance of asymmetrical concentrating photovoltaic/thermal modules over a short incidence angle interval. It is therefore important to quantify these impacts precisely. The impact on the electrical performance of the optical properties of an asymmetrical photovoltaic/thermal CPC-collector was measured in Maputo, Mozambique. The measurements were carried out with the focus on attaining a high resolution incidence angle modifier in both the longitudinal and transversal directions, since large variations were expected over small angle intervals. A detailed analysis of the contribution of the diffuse radiation to the total output was also carried out. The solar cells have an electrical efficiency of 18% while the maximum measured electrical efficiency of the collector was 13.9 % per active glazed area and 20.9 % per active cell area, at 25 °C. Such data make it possible to quantify not only the electrical performance for different climatic and operating conditions but also to determine potential improvements to the collector design. The electrical output can be increased by a number of different measures, e.g. removing the outermost cells, turning the edge cells 90°, dividing each receiver side into three or four parts and directing the tracking, when used, along a north-south axis.

 

Keywords

CPC-collector; PVT hybrid; incidence angle modifier; asymmetric collector; electrical efficiency

Conflicts of Interest

The authors declare no conflicts of interest.

References

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