Optical modeling of photovoltaic modules with ray tracing simulations

The increasing importance of photovoltaic energy conversion entails the need for an accurate prediction of the energy yield of photovoltaic systems. Optical modeling is an important part of such calculations. Compared to modeling bare solar cells, the modeling of photovoltaic modules is more complex in that it has to deal with optical effects on size scales varying by over six orders of magnitude. Moreover, objects of finite lateral extent with laterally inhomogeneous optical properties and illumination conditions which may be very different from tabulated standard testing conditions have to be considered. For an accurate description of the optical properties of photovoltaic modules, simple analytic formulas are therefore often not sufficient. In this chapter, we discuss the optical modeling of photovoltaic modules by ray tracing simulations, which have become popular due to their flexibility and increasing computation capacities. We cover basic aspects of optical modeling and ray tracing as well as specific requirements for photovoltaic modules and give some application examples. The chapter concludes with an overview of software tools for optical modeling of photovoltaic devices.