TECHNO-ECONOMIC ANALYSIS AND OPTIMAL DESIGN OF AN OFF-GRID HYBRID PV/WIND/DIESEL SYSTEM WITH BATTERY STORAGE

Diesel power technology has been utilized worldwide, especially in remote regions, because of its low initial capital cost. But it has negative effects on the surrounding environment and causes global warming. Also the power supply of off-grid remote area and applications at minimal cost and with low emissions is an important issue when discussing future energy concepts. In Iran, the cost of fuel is highly subsidized. If Iran removes the fuel subsidy, the cost of diesel fuel would increase and the renewable energy systems would become more attractive. This paper presents techno-economic analysis, modeling and optimization of a photovoltaic (PV)/wind/diesel/batterybased hybrid system for electrification to an off-grid remote area located in Rafsanjan, Iran, for different diesel generator fuel price scenarios. For this location, different hybrid (PV/wind/diesel/battery) systems are studied and compared in terms of cost and pollution for two scenarios. For cost analysis, a mathematical model is introduced for each system's component and then, in order to satisfy the load demand in the most cost-effective way, two discrete versions of particle swarm optimization algorithm are developed to optimally size the systems components. As an efficient search method, PSO has simple concept, is easy to implement, can escape local optima, by use of probabilistic mechanisms, and only needs one initial solution to start its search. Simulation results indicate that only under a subsidized diesel fuel price scenario, the diesel-only system has the minimum cost, but by the elimination of diesel fuel price subsidies and reduce the costs of photovoltaic panels and wind turbines, the role of the diesel generator decreases in hybrid (PV/wind/diesel/battery) energy systems.