ABSTRACT The increase in energy demand in Brazil encourages the country to increasingly invest in generation of electric energy, where the demand for other renewable sources increases gradually because they have a lower impact on the environment. The use of Grid-Connected Photovoltaic Systems (GCPVS) is a viable solution for the country, since it presents favorable natural conditions for the use of solar energy.

This study approaches the current scenario of three photovoltaic systems installed in Curitiba in 2016 and part of 2017:

Green Office (GO) located in Curitiba Campus Downtown, Curitiba Campus Neoville, both of the Federal Technological University of Paraná (UTFPR), as well as a residence. By means of performance parameters, performance analysis of these systems were carried out and, in order to measure the length of time of the return of the initial investment in its installation, a study of the economic viability of these systems according to the current rate model in Brazil through economic engineering tools was carried out: Simple Payback and Discounted Payback, Net Present Value and Internal Rate of Return. Finally, the application of the saved value of electric energy bills was simulated in a bank account during the system´s lifespan.