Luminescent solar concentrators: From experimental validation of 3D ray-tracing simulations to coloured stained-glass windows for BIPV

Abstract

Luminescent solar concentrators (LSC) are a promising technology for building integrated photovoltaics (BIPV) given the wide variety of forms and colours that can be realised. Given the flexibility of the technology, the use of ray-trace modelling is indispensable in the design, performance evaluation, and optimisation of LSCs. This work begins by comparing a threedimensional (3D) ray-trace model of an LSC with experimental results. The study includes 70 samplesboth square and circular LSCs, containing five different fluorescent organic dyes (BASF Lumogen) each at seven different concentrations. The figure-of-merit used for performance evaluation was the average power density determined at the LSC edge sheet, measured using an optical fibre connected to a spectrometer. The results demonstrate that 3D ray-trace results gives good agreement with the experimental measurements, to within around ±5% within a wide concentration range (optical density = 0.05-8) and a maximum difference of ±13%. The wide range of colours achieved is presented in a CIE chart. Overall, the validated experimental results give confidence in the use of modelling for future larger LSCs for BIPV. Therefore, based on these results and the colours achievable, a model of a stained-glass window is constructed and its performance throughout a solar day is simulated.

Cylindrical array luminescent solar concentrators: performance boosts by geometric effects

“…Another study quantified the maximum level of coverage an LSC, albeit a red dye doped one, on a facade is 25%, for both interior and exterior viewing [7]. The potential for LSC stained-glass window designs has been reported on, and 3D ray-trace models have been created which have been confirmed experimentally to be useful for optimising LSCs in various shapes and sizes [8]. Curved LSCs can find also applications in building integration, for example being wrapped around a streetlight pole as both an aesthetic and electricity generating structural element [9].…”

“…Only one study measures a fibre array CLSC performance over the course of a month [10]. LSC tilt and its effect of performance has been looked at for flat LSC geometries, both in outdoors conditions [23] and in laboratory conditions [8,24]. Furthermore, whilst the geometrical effect of a cylinder array on external reflections due to angle of incidence of incoming light was touched on [14], there is an absence on the investigation on LSC cylindrical array performance in real world lighting conditions such as the light output as a function of angle of incidence of incoming light.…”

State-of-the-art review of solar design tools and methods for assessing daylighting and solar potential for building-integrated photovoltaics

“…Nevertheless, this model is still able to properly simulate a wide range of physical phenomena. Although wave models are mostly used to simulate PV under direct sunlight source they not capable enough to simulate complex shapes under diffuse sunlight [136]. On the contrary, geometric optics model represented by ray tracing approach is more flexible at simulating these geometries under both direct and diffuse sunlight.…”

“…Most of them used in-house software tools and specific models to simulate different PV cell types. On the contrary, implementations of ray tracing tools from other disciplines are presented by Kerrouche et al [136] who performed experimental validation of commercially available SPEOS Optisworks 3D optical ray-tracing simulations for luminescent solar concentrators BIPV thus achieving good of <7%. This software is also used in a simulation of a novel non-imaging stationary window integrated 3-D solar concentrator (SEH) developed by Sellami and Mallick [145].…”

Design and development of a reflective membrane for a novel Building Integrated Concentrating Photovoltaic (BICPV) ‘Smart Window’ system

“…Sabry [33] developed a lowconcentration, PV-coupled prismatic segmented glazing façade that can convert most of the direct solar radiation incident on buildings façades to electricity, while allowing diffuse daylight transmitting to the interior of the building. Kerrouche et al [34] studied the performance of Luminescent Solar Concentrators (LSC) using 3D ray-tracing simulation. The study included 70 samples -both square and circular LSCs, containing five different fluorescent organic dyes each at seven different concentrations.…”