Energy efficiency, rationalization of energy and water consumption in popular houses

This paper's purpose is to investigate the energy efficiency with the installation of the photovoltaic system in residences of social interest, seeking mainly to meet the demands of higher consumption of electric energy such as the showerhead. An estimatedproposal of the Energy Efficiency Program carried out by the Goiana Housing Agency in which it will install 1,199 photovoltaic systems in the housing units of social interest located in the state of Goiás-Brazil. The study estimated the monthly consumption of inputs (water, electricity and gas) in the electric showerhead, gas heater, hybrid shower, solar heater and electric boiler; the total monthly costs for a daily bath per inhabitant were calculated by using the average of 4.9 inhabitants per household. To this comparison was inserted the proposed system of photovoltaic production with the use of electric showerhead. Considering the inputs, the installation cost divided by the life expectancy of the equipment, it was proven that the solution with the lowest cost per bath it the photovoltaic with an expense of 9.38U$. month-1, favorable economic result if compared, for example, to solar heating with an expense of 26.62U$. month-1. The factorssuch asthe average volume of water used per system, average bath time, life expectancy of the equipment, determine the result.