FOTODIM—Software for Sizing of Photovoltaic Systems

This study addresses the development of a computational tool for the sizing of photovoltaic systems interconnected to the grid (grid-tied) and isolated (off-grid) systems. The calculations for the sizing were obtained from the CRESESB Engineering Manual for Photovoltaic Systems, the GREENPO Photovoltaic Systems Technology, Design and Installation Manual, and the BLUESOL Solar System Introduction Digital Book. With knowledge of the latitude, longitude and altitude data of the site, the tool calculates the angle of the modules for better absorption of the photovoltaic radiation. For systems connected to the grid, it is also necessary to provide information on the consumption of the building to be serviced by the photovoltaic system. For isolated systems, in addition to information on the site, it is necessary to know the demand and consumption of the building. Decision-making criteria are based on economic analysis, according to indexes such as Net Present Value (NPV), Internal Rate of Return (IRR), and Discounted Payback. The screens developed for the sizing tool and examples of sizing of both photovoltaic systems are presented as results, through tables and graphs. The developed software is reliable, and all calculations have theoretical basis.