Model-Based Assessment of the Incident Angle Modifier on the Annual Angular Losses and Gain of PV Modules in Tracking Systems

In a competitive photovoltaic (PV) solar energy market, precise and accurate modeling of the energy produced by a PV power plant is required to obtain the best technical and economic project. In particular, slight differences in the predicted energy produced are relevant due to the project size. Typically, the energy calculation includes the direct and diffuse components of the solar radiation at normal incidence. The incident angle's influence is considered using the incident angle modifier (IAM). This study model the experimental values of the IAM available in the literature using the physical, ASHRAE, SANDIA, and Martin-Ruiz models. Also, a new mathematical model based on only one parameter to describe the IAM is presented. The IAM is used to determine the annual angular losses (AAL) and energy gain using different solar tracking strategies compared with the horizontal plane for locations at different latitudes and climate zones. The results showed that the IAM is sensitive to radiation under indoor and outdoor conditions, quantified by the parameters employed to fit the experimental data. Also, results revealed that the gain in PV systems using solar tracker systems is improved if the AAL is considered.