Hybrid Photovoltaic Systems

Abstract

Hybrid power systems (HPS) combine two or more sources of renewable energy as one or more conventional energy sources. The renewable energy sources such as photovoltaic and wind do not deliver a constant power, but due to their complementarities their combination provides a more continuous electrical output. Hybrid power systems are generally independent from large interconnected networks and are often used in remote areas. The purpose of a hybrid power system is to produce as much energy from renewable energy sources to ensure the load demand. In addition to sources of energy, a hybrid system may also incorporate a DC or AC distribution system, a storage system, converters, filters and an option to load management or supervision system. All these components can be connected in different architectures. The renewable energy sources can be connected to the DC bus depending on the size of the system. The power delivered by HPS can vary from a few watts for domestic applications up to a few megawatts for systems used in the electrification of small villages. Thus, the hybrid systems used for applications with very low power (under 5 kW) generally feed DC loads. Larger systems, with a power greater than 100 kW, connected to an AC bus, are designed to be connected to large interconnected networks. Hybrid systems are characterized by several different sources, several different loads, several storage elements and several forms of energy (electrical, thermal).