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

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 research topic, a renewable energy hybrid system is designed to supply energy to a pumping station in the city of Santa Rosa, RS, Brazil. For this aim, three cases are proposed and simulated in the software HOMER to obtain the optimal solution with the lower cost: a) wind-photovoltaic-diesel connected to the grid; b) wind-photovoltaic-diesel isolated; and c) wind-photovoltaic iso-lated. All three hybrid systems are viable and can supply energy for the pumping station, but their costs are still high. Govern-ment incentive programs, development of new technologies and penalties for the emission of pollutant gases can make these re-newable 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.