ECONOMIC FEASIBILITY OF ON-GRID PHOTOVOLTAIC SYSTEMS IN A SINGLE-FAMILY HOUSE IN RIO DE JANEIRO CITY

Abstract

Brazil is a tropical country with favorable conditions for the generation and utilization of solar energy. This energy source becomes even more attractive when considering the dry periods that impact hydroelectric power generation in the country, resulting in an increase in energy costs reflected monthly in consumers' bills through tariff flags. In order to enhance residential architectural designs and promote energy efficiency, a feasibility study of photovoltaic systems was conducted, considering key economic indicators and the current tariff flags. To accomplish this, research was conducted in collaboration with Mounting Companies for a case study located in the city of Rio de Janeiro, adopting technical assumptions commonly used for residential photovoltaic system sizing. For the graphical sizing of the case study, factors such as the environment and summer and winter solstices were taken into account, and a shadow study was conducted to assess the potential loss of power generation by the photovoltaic system throughout the year. The shadow study revealed that, during both solstices, the optimal time for power generation by photovoltaic systems is between 9 a.m. and 6 p.m. Essentially, the calculated values of NPV (Net Present Value) and IRR (Internal Rate of Return) indicate that the project is economically viable and particularly advantageous during the yellow and red tariff flags, situations in which energy costs tend to be higher for consumers.