A wind PV diesel hybrid system for energizing a sewage station in Santa Rosa, in southern Brazil

Abstract

Renewable energy hybrid systems generate electricity by multiple sources of energy and can be used in replacement of fossil fuels for many applications. Like most economic sectors, sanitation systems can benefit from the use of these renewable energy hybrid systems for the expansion of their activities. In this paper, a renewable energy hybrid system is designed to supply electricity to a water pumping station in the city of Santa Rosa, RS, Brazil. Three cases are proposed and designed in the software HOMER: wind-photovoltaic-diesel connected to the grid, wind-photovoltaic-diesel isolated and wind-photovoltaic isolated. The optimized system, the one with the lower cost, is determined. All three hybrid systems are viable and can supply energy for the pumping station, but their costs are still high. Government incentive programs, development of new technologies and penalties for the emission of pollutant gases can make these renewable energy hybrid systems become even more competitive. A consumption of 1.5 kW for pumping of sewage, according to the results obtained, can be attended with three combinations: a grid-connected diesel photovoltaic system, an isolated diesel photovoltaic wind system and an isolated photovoltaic wind system. These systems would have a total net present cost of US$ 47,867, US$ 85,381 and US$ 118,753, respectively, with energy costs equal to US $ 0.291 per kWh, US $ 0.581 per kWh and US $ 0.721 per kWh respectively. The cheapest combination of these three includes a 7.5 kW wind turbine and a 1 kW diesel system.