Topology optimization for high-resolution designs: Application in solar cell metallization

Due to global population growth and industrial development, there is a rising demand for energy. It is desired that this demand is met in a cleaner and more sustainable way. Among the various renewable energy sources, solar power is experiencing remarkable growth throughout the world. To ensure that solar power can be a sustainable solution for the future energy demands, intensive research is being conducted to make solar cells more efficient and thereby reduce the cost of solar energy. Solar cells have metallization patterns on the front side to collect current generated in the semiconductor layer. The performance of a solar cell significantly depends on the amount of electrode material used for metallization, and the pattern in which it is deposited. There exist several optimization approaches to optimize the metallization distribution on the front surface of solar cells. However, due to the numerical simplifications associated with these methods, only limited gains in power output are observed. Moreover, the applicability of these methods is historically restricted to rectangular or circular domains. There has recently been a drive towards increased freeform photovoltaic installations. Given that these shapes can be very arbitrary, the optimal metallization patterns for such geometries can be expected to be complex, and the traditional methods cannot be used to design them.