Small renewable hybrid systems for stand alone applications

To provide renewable energy to stand alone applications the generation system should be composed of different types of energy sources to make better use of the natural resources in these applications. A common practice is to combine wind and solar PV energies in the so called hybrid renewable systems. Due to the long distance, and difficult access the overall system used in these applications must be reliable. And the reliability of the system, specially the inverter used to regulate the AC voltage, is one of the main problems associated to these systems, and is responsible for the lack of confidence in renewable systems at several locations in Brazil. This paper shows the initial results of using renewable hybrid systems specially designed for isolated areas, focusing attention on reliability, efficiency and expansion flexibility. It presents the system description, mode of operation, inverter design, and experimental results measured in a pilot plant located in Lencois Island, a small isolated community in the northeast region of Brazil.