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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. [ABSTRACT FROM AUTHOR]

Abstract: The power plants based on renewable sources face various acceptance difficulties mainly due to high initial costs and low overall efficiencies. A way to improve performance of these systems is to utilize more than one type of source of energy chosen to provide some degree of complementarity. An interesting, albeit improbable, combination is obtained using hydroelectric and photovoltaic energy, taking advantage of the complementarity between these two types of sources coupled to reservoir and/or battery storage. This paper discusses energy complementarity in time and proposes a numerical dimensionless index, evaluating this energy complementarity between two types of energy sources, in the same or in different locations, or between two sources of the same type in different locations. In the end, the results of the application of this index to the solar and water availabilities over the state of Rio Grande do Sul, in southern Brazil, is presented in the form of maps. [Copyright &y& Elsevier]

Hybrid energy systems have higher initial costs than systems that are based on only one renewable resource, but allow for the fulfillment of the demands of consumer loads with lower values for the cost of energy. The possible complementarity between the resources used can contribute to a better use of the available energy. On a large scale, complementarity between power plants can serve as a tool for the management of energy resources. A complete evaluation of complementarity needs to consider three components: time complementarity, energy complementarity, and complementarity between amplitudes of variation. Complementarity can also be assessed between energy resources in one place (which may be termed temporal complementarity) and between resources at different sites (termed spatial complementarity). This paper proposes a method for quantifying spatial complementarity over time and for its expression through maps. The method suggests the establishment of a hexagonal network of cells and the determination of complementary roses for each cell that contains power plants. This article also applies the method proposed to some hydroelectric plants and wind farms in the State of Rio Grande do Sul, in southern Brazil, and present the map of spatial complementarity in time obtained. [ABSTRACT FROM AUTHOR]