Optimal sizing of solar-wind hybrid system

Autonomous systems on the basis of solar and wind generators in combination with a battery storage and diesel generator as back up are an option for the supply of electric power to the loads at remote locations. These systems may be configured with solar generator or wind generator alone, or with the combination of both. To decide on system configuration that is best suited to a specific case, it is necessary to identify all possible configurations, that can satisfy the load demand at certain desired reliability level. From these configurations, an optimal one is extracted on the basis of economical analysis. This paper presents the development of a computational model for optimal sizing of solar-wind hybrid energy system (SWHES). The performance of solar and wind system is evaluated through more accurate and practical mathematical models, combining with hourly measured meteorological input data and load data. The reliability measures in terms of loss of power supply probability (LPSP) and the total life cycle cost have been used as the indices for evaluation of different configurations. Load following strategy with a fixed discharge threshold one hour dispatch is used to discharge the stored renewable energy in the battery storage. Methodology used in this model, allows quick identification of optimal configuration based on user´s desired reliability level and economical (life cycle cost) performance of system. Program has been developed in MATLAB 6.5 environment using energy balance calculation method.