Optimal sizing of a grid-connected hybrid system for north-west of Iran-case study

In this paper, a grid-connected hybrid wind/photovoltaic/battery power system is designed. The aim of design is minimization of annualized cost of the hybrid system over its 20 years of operation. The optimization problem is subject to economic and technical constraints. System costs involve investments, replacements and operation and maintenance as well as loss of load costs. The technical constraint, related to system reliability, is expressed by the equivalent loss factor. The reliability index is calculated from components' failure. Finally, hybrid system with best configuration that has minimum cost and can satisfy the constraints is selected. Particle Swarm optimization (PSO) algorithm is used for optimal sizing of system's components. The characteristics of components are commercially available and this study is performed for the special region in North - West of Iran.