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An experiment was conducted to test the optical efficiency of the lenses of the Concentrating Photovoltaic Glazing (CoPVG) concept. The CoPVG is a seasonal glazing system consisting of longitudinal prismatic lenses. The lenses concentrate sunlight onto the focus where Photovoltaic (PV) cells are bonded, generating electricity while simultaneously preventing excessive glare indoors during summer. The system transmits sunlight for daylight purposes in winter. The experimental results were compared with an analytical model developed at Ulster University. Although there were discrepancies between the model and the experimental results, the model can still predict the optical performance of the lenses reliably, and can therefore still provide an overview of the concept's optical performance. The model was then used to create a visual representation of the glazing's annual optical performance, demonstrating how the glazing responds to changes in the sun's position in the sky throughout the year. This analysis allows for balancing the need for natural lighting and energy generation, and so enables designers to evaluate annual optical performance of the CoPVG lens quickly and accurately. A case study of a building in Belfast is presented to demonstrate the application of the model. As an example, the results indicate that utilizing the lenses in glazing towards the south leads to a shift in its performance from room lighting to shading on 1st April, and vice versa on 15 September. The analyses also show that utilizing the CoPVG lenses can potentially enhance the electrical output power of the glazing ranging between 5% and 8% and from 46% up to 52% during winter and summer, respectively, compared with traditional Semi-Transparent Photovoltaic (STPV) glazing with the same opaque area percentage. [ABSTRACT FROM AUTHOR]

An experiment was conducted to test the optical efficiency of the lenses of the Concentrating Photovoltaic Glazing (CoPVG) concept. The CoPVG is a seasonal glazing system consisting of longitudinal prismatic lenses. The lenses concentrate sunlight onto the focus where Photovoltaic (PV) cells are bonded, generating electricity while simultaneously preventing excessive glare indoors during summer. The system transmits sunlight for daylight purposes in winter. The experimental results were compared with an analytical model developed at Ulster University. Although there were discrepancies between the model and the experimental results, the model can still predict the optical performance of the lenses reliably, and can therefore still provide an overview of the concept’s optical performance. The model was then used to create a visual representation of the glazing’s annual optical performance, demonstrating how the glazing responds to changes in the sun’s position in the sky throughout the year. This analysis allows for balancing the need for natural lighting and energy generation, and so enables designers to evaluate annual optical performance of the CoPVG lens quickly and accurately. A case study of a building in Belfast is presented to demonstrate the application of the model. As an example, the results indicate that utilizing the lenses in glazing towards the south leads to a shift in its performance from room lighting to shading on 1st April, and vice versa on 15 September. The analyses also show that utilizing the CoPVG lenses can potentially enhance the electrical output power of the glazing ranging between 5% and 8% and from 46% up to 52% during winter and summer, respectively, compared with traditional Semi-Transparent Photovoltaic (STPV) glazing with the same opaque area percentage.

Abstract Geometrically equivalent V-trough and compound parabolic concentrators (CPC) were simulated to characterise the variation in optical efficiency using ray tracing modelling with COMSOL Multiphysics. The effect of CPC truncation and V-trough side wall angles were studied. The truncated CPC demonstrated much improved light acceptance outside the designed angle of acceptance when compared to the original CPC design and V-trough-like characteristics past the original design acceptance angles, consequently reducing material consumption for the manufacture of truncated CPC and therefore reduction in the cost of the system. Truncated CPCs showed optical efficiency equal to their full height counterparts, but a lower concentration ratio (4 at full, 3.6 at half and 2.7 at 50 mm height) due to an equivalent reduction of the inlet aperture size. The V-trough had a higher optical concentration ratio over 15–30° angle of incidents (AoI), with the CPC taking over from 30° AoI upwards. Experiments were performed on a 50 mm truncated CPC and a 22° Trough Wall Angle (TWA) V-trough collector under outdoor conditions. Experimentally measured data showed good correlation with ray tracing simulation results. Both experimental and the ray tracing analyses showed the CPC concentrator achieving a 2.4% higher power output compared to the V-trough design. Highlights • Novel Comsol MultiPhysics modelling to automatically update geometry on the fly and run large batches of simulations. • BIPV/BAPV suitable truncated CPC with a 80% reduced height at a mere 30% loss of concentration. • CPC has 13% higher optical performance than V-trough. • Experimental power output of CPC 2.4% higher than an equivalent V-trough. [ABSTRACT FROM AUTHOR]