Open source photovoltaic system performance modeling with python

Several tools exist for modeling the annual energy output of photovoltaic (PV) solar systems. However, open source frameworks are not widely available and tend to be procedural. Moreover, they are oriented toward the modeling of the solar resource instead of the optimization of PV system design. Open source software allows for peer revision, collaboration and rapid development. Furthermore, localized optimizations are possible such as adaptation to local requirements or different weather data formats. In this paper, solpy, an object oriented open source python implementation, is presented. This software is capable of using historic or forecasted weather data to predict system performance as well as validate certain design constraints such as system voltage and conductor sizing. The developed software, solpy, compares favorably against NREL PV Watts and System Advisor Model.