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Solar cells made from multicrystalline silicon (mc-Si) wafers play an important role in photovoltaics. Nevertheless, tools for the optical simulation of these devices are scarce. In the present work, the reflectance and charge carrier generation of mc-Si cells and modules are for the first time simulated successfully in the complete spectral range including light trapping and escape light, as the comparison with measured reflectance of the finished cells and mini-modules shows. The "spherical caps" geometry is used to model the front surface reflection of iso-textured silicon solar cells. The characteristic angles of the spherical caps are determined from the reflectance of iso-textured wafers for three different texture strengths. Based on this calibration, the reflectance and charge carrier generation rates of cells encapsulated with EVA and glass are simulated and analysed. Iso-textured cells with full-area aluminium back surface field (Al-BSF) and with passivated emitter and rear (PERC) are quantitatively compared regarding the photo-generated current density j Ph . The simulations demonstrate that the direct cell-to-module loss of iso-textured mc-Si cells with Al-BSF (0.7 mA/cm²) is smaller than for PERC cells (1.2 mA/cm²).

In this study we assess the reproducibility of the honeycomb texturing process, and we compare experimental values to a simulation. Our results show that the honeycomb-texture can be simulated with the OPAL program. It calculates the losses of any angle of incidence, where the short computation time is achieved by decoupling the ray tracing from the Fresnel equation. We investigate various surface morphologies and their impact on reflection values. The samples were etched at different etching times, whereby the honeycomb geometries were changed. Using our optimal acid etching solution ratio, we are able to fabricate a HC-texture with a reflectivity of R = 19.4 % (ω = 85°). Between the simulation values and those of the measurement, we see a difference of R = 0.3 %abs. This small deviation causes the relatively inaccuracies of the simulation and the measured samples. The focus is to simulate the different honeycomb structures and compare the values with the experimental values

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