Critical Retrospect on Conventional and Luminescent Solar Concentration Devices

Problem statement: Conventional solar concentrators are only sensitive for the beam radiation and they function poorly in overcast sky conditions. Even under a clear sky condition, trackers are always needed for conventional solar concentrators. Static concentrators always come with a poor concentration rate without a tracker and the light concentrated by normal Luminescent Solar Concentrators (LSC) could not be transported by optical fibers to a remote place since the light produced by LSCs is not a pointolite. Approach: Through a critical literature review and discussion, this article retrospects the merits and demerits of recent conventional solar concentrators and Luminescent Solar Concentrators (LSC). Results: Results summarized the limitations in current day lighting related solar concentration devices. As an approach for energy saving, daylight has a disadvantage of not being able to reach many areas of a building such as store rooms, basements and corridors and it also brings heat gain with the light. Light pipes were designed to transport daylight to unreached areas, but light pipes have their difficulties for wiring, so that optical fibers are considered as the best approach for the daylight transportation so far. However, the optical fiber needs a pointolite for the light transportation. Various solar concentrators that were designed using optical approaches such as using mirrors or lens for the solar energy concentration. Since they are only sensitive for the beam irradiation, they function poorly in the cloudy weather and the diffuse light conditions and even if they are under a clear sky condition, trackers are always needed. Luminescent Solar Concentrators (LSC) and some static solar concentrators were then designed as the diffuse light solution and the static solution, respectively. Static concentrators always come with a low concentration rate without a tracker and the light concentrated by normal LSCs could not be transported by optical fibers to a remote place since the light produced by an LSC is not a pointolite. Conclusion/Recommendations: New solar concentration systems need to be developed to mitigate the above-mentioned limitations. Future studies especially cross disciplinary researches on developing new solar concentrators in mitigating those limitations as discussed in this study are highly recommended.