Optimization of cell to module conversion loss by reducing the resistive losses

Conventional silicon based photovoltaic industries, which convert silicon cells to modules attracted the attention of the researchers due to the cell to module conversion power losses. The conversion power losses are due to the various parameters such as shadow effect, inherent properties of the solar cells, properties of the materials used for fabricating the module etc. Among them, the inherent properties of the solar cells play a major role in module power. The electrical properties of the solar cell such as series resistance and fill factor drive the conversion power losses in the module. By increasing the number of contact points, the losses will be reduced. In this work it is found that by introducing an extra bus bar in metallization pattern leads to a great reduction in conversion losses. The fill factor gain is observed in three bus bar based modules compared to two bus bar based modules because of the contact points per cell increase which lead to low resistance losses. It is obvious that the power gain in three bus bar modules dominates shadowing loss due to an additional bus bar. A systematic approach on minimising the cell to module conversion loss by optimizing the front contact bus bar width has been studied. It is important that beyond the optimum value of bus bar numbers and its width the shadowing loss will dominate over the gain.

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