Viability for installing on-grid photovoltaic energy at residences: estimated payback in several economic scenarios

Abstract

The use of photovoltaic energy in homes worldwide grows every day and seems to be very promising in countries with great solar radiation such as Brazil, even more with the possibility of offsetting electricity credits in the energy distributor (net metering). However, due to taxes, the cost compared to other countries is high. An On-Grid photovoltaic electric power generation-consumption model is built based on a middle class residence located in São Paulo. It comprises the dimensioning of the photovoltaic system necessary to supply the consumption needs as well as the possibilities of paying for its implementation. Five scenarios were evaluated: one in case the residents have the amount to pay at the moment of the investment, and four other scenarios when it is necessary to ask for a loan to pay for the investment. It was observed that although the investment return (payback) is not low if applications were made during the loan, there is a decrease in the impact of the interest rate.